Stereochemical nomenclature. Search results for \"seniority of substituents\" Chemistry of heterocyclic biologically active substances textbook

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2. Kahn-Ingold-Prelog notation (R-S-nomenclature)

Since it is impossible to use the D-L-nomenclature without setting the direction of orientation of the projection formula, and since many compounds contain more than one asymmetric carbon, in 1956 R. S. Kahn, D. K. Ingold and V. Prelog developed the R-S notation system for the spatial connection configuration, in which R stands for right (rectus) and S for left (sinister). (Note that R and S are also Kahn's initials.)

The spatial configuration of substituents near each asymmetric carbon atom is designated according to the following rules:

1. Note the atomic number of each of the atoms directly attached to the asymmetric carbon atom in question.

2. Arrange these atoms in descending order of atomic number.

3. If the substituents on the asymmetric carbon atom are two atoms with the same atomic number (for example, two other carbon atoms), the atomic number of the substituents on these attached atoms is taken into account. An atom with a substituent having a higher atomic number is placed in front of an atom whose substituent has a lower atomic number. The order of precedence of frequently occurring substituents on asymmetric carbon is as follows: I, Br, CI, SH, OH, NO 2, NH 2, COOR, COOH, CHO, CR 2 OH, CHOHR, CH 2 OH, C 6 H 5 , CH 2 R , CH 3 , H. Atoms connected by double and triple bonds are counted twice or thrice, respectively. For example:

4. Position the asymmetric carbon atom so that the atom with the lowest atomic number (most often H) is facing away from the observer's eye.

Note that any pair of Fisher's two-dimensional projections can be swapped or the positions of three substituents can be changed without changing the true spatial structure. For example, the position of H, OH and CH 2 OH in the Fischer projection for D (+) -glyceraldehyde can be depicted in different ways:

If you rotate this model 120° to the right, it will match model (1).

5. Consider three substituents located in front of the asymmetric carbon atom. (Recall that the atom with the lowest atomic number is behind the asymmetric carbon atom.) Determine how the atoms are arranged in descending order of atomic number - clockwise (right R configuration) or counterclockwise (left S configuration).

For example, in glyceraldehyde, the order of the substituents attached to the asymmetric carbon atom, according to the above rules, will be OH, CHO, CH 2 OH and H. In order to determine whether the asymmetric carbon will be R or S, we will arrange the molecule so: so that the H atom is at the bottom in a two-dimensional formula, or behind an asymmetric carbon atom in a three-dimensional formula (see rule 4).

STEREOCHEMICAL NOMENCLATURE(from Latin in menclatura - list, list), is intended to designate spaces. chemical structures. connections. The general principle of stereochemical nomenclature (IUPAC rules, section E) is that spaces. the structure of the connection denoted by prefixes added to the names without changing these names. and numbering in them (although sometimes stereochemical features can determine the choice between possible alternative numbering methods and the choice of the main chain).

At the heart of most stereochem. notation lies the sequence rule, which unambiguously establishes the precedence of substituents. Those of them are considered senior, in which an atom with a large atomic number is directly connected with the considered chiral (see Chirality) element (for example, asymmetric atom, double bond, cycle) (see table). If these atoms are the same in seniority, then the "second layer" is considered, which includes atoms associated with the atoms of the "first layer", etc., until the first difference appears; the numbers of atoms linked by a double bond are doubled when determining seniority. Naib. a common approach to designating the configuration of enantiomers is to use the R,S system. The designation R (from lat. rectus-right) gets one of the enantiomers, in which, when considering the model from the side opposite to the junior substituent, the seniority of the remaining substituents falls clockwise. Falling seniority counterclockwise corresponds to the S-designation (from Latin sinister-left) (Fig. 1).

Increasing seniority of substituents at the chiral center:

Rice. 1. Scheme for determining the seniority of substituents in organic compounds.

For carbohydrates, a-hydroxy acids, a-amino acids, the D, L-system is also widely used, based on a comparison of the configuration of the considered asymmetric. center with the configuration of the corresponding enantiomer of glyceraldehyde. When considering the Fisher projection formsmule the location of OH or NH 2 groups on the left is indicated by the symbol L (from lat. laevus - left), on the right - by the symbol D (from lat. dexter - right):

s-Diastereomers (classical diastereomers) in the simplest cases are designated as meso- and racemic forms or erythro- and threo-forms:

For complex structures, when all six substituents are two asymmetric. centers are different, other systems have been proposed. For example, pref, parf (pref, parf) - designations are based on considering the order of falling precedence (according to the sequence rule) in Newman's formulas: with the same falling direction - pref (eng. priority reflective), with the opposite - parf (eng. priority antireflective ). For example:

To describe spaces. connection buildings. with a C \u003d C bond, as well as cyclic in cases that exclude discrepancies, they use the designations cis and trans (the same or related substituents are located respectively on one and on opposite sides of the plane of the double bond or cycle),e.g. cis-2-butene (form I), trans-cyclobutane-1,2-dicarboxylic acid (II).

Such designations become ambiguous for alkenes like abC=Cde, oximes, azomethines. In these cases, the Z,E nomenclature is used [senior substituents on the double bond are located respectively. one by one(Z, from German zusammen - together) and differently (E, from German.entgegen-opposite) sides of the double bond plane], e.g.(Z)-2-chloro-2-butene acid (III), (E,E)-benzyldioxime (IV).

In the presence of three or more substituents in the alicyclic molecule. or sat. heterocyclic compounds use the r,c,t nomenclature. One of the substituents is chosen for the "reference" -r (reference, from English reference). For substituents lying on one side of the ring plane with a reference atom, use the designation c (from cis-цuc), for substituents on the other side of the ring plane-t (fromtrans-trans), e.g. t-2-c-4-dichloro-cyclopentane-M-carbo new kit (V).

In a number of steroids, the designation of spaces. locationsubstituents are made on the basis of a conditional flat f-ly.

Substituents far from the observer are a,close to the observer - b. e.g. 11b,17a,21-trihydroxy-4-pregnene-3,20-dione (

CHAPTER 7. STEREOCHEMICAL BASIS OF THE STRUCTURE OF ORGANIC COMPOUNDS

Stereochemistry (from the Greek. stereos- spatial) is "chemistry in three dimensions". Most molecules are three-dimensional (threedimentional, abbreviated as 3D). Structural formulas reflect the two-dimensional (2D) structure of the molecule, which includes the number, type, and sequence of binding atoms. Recall that compounds having the same composition but different chemical structure are called structural isomers (see 1.1). A broader concept of the structure of a molecule (sometimes figuratively called molecular architecture), along with the concept of chemical structure, includes stereochemical components - configuration and conformation, reflecting the spatial structure, i.e., the three-dimensionality of the molecule. Molecules that have the same chemical structure may differ in spatial structure, i.e., exist in the form of spatial isomers - stereoisomers.

The spatial structure of molecules is the mutual arrangement of atoms and atomic groups in three-dimensional space.

Stereoisomers are compounds in whose molecules there is the same sequence of chemical bonds of atoms, but a different arrangement of these atoms relative to each other in space.

In turn, stereoisomers can be configuration And conformational isomers, i.e. vary accordingly configuration And conformation.

7.1. Configuration

A configuration is the arrangement of atoms in space without taking into account the differences that arise due to rotation around single bonds.

Configurational isomers can transform into each other by breaking one and forming other chemical bonds and can exist separately as individual compounds. They are divided into two main types - enantiomers And diastereomers.

7.1.1. enantiomers

Enantiomers are stereoisomers that relate to each other as an object and an incompatible mirror image.

Only enantiomers exist as enantiomers. chiral molecules.

Chirality is the property of an object to be incompatible with its mirror image. Chiral (from the Greek. cheir- hand), or asymmetric, the objects are the left and right hand, as well as gloves, boots, etc. These paired objects represent an object and its mirror image (Fig. 7.1, a). Such items cannot be completely combined with each other.

At the same time, there are many objects around us that are compatible with their mirror image, that is, they are achiral(symmetrical), such as plates, spoons, glasses, etc. Achiral objects have at least one symmetry plane, which divides the object into two mirror-identical parts (see Fig. 7.1, b).

Similar relationships are also observed in the world of molecules, i.e. molecules are divided into chiral and achiral. Achiral molecules have planes of symmetry, chiral ones do not.

Chiral molecules have one or more centers of chirality. In organic compounds, the center of chirality is most often asymmetric carbon atom.

Rice. 7.1.Reflection in the mirror of a chiral object (a) and a plane of symmetry cutting the achiral object (b)

Asymmetric is a carbon atom bonded to four different atoms or groups.

When depicting the stereochemical formula of a molecule, the symbol "C" of the asymmetric carbon atom is usually omitted.

To determine whether a molecule is chiral or achiral, it is not necessary to represent it with a stereochemical formula, it is enough to carefully consider all the carbon atoms in it. If there is at least one carbon atom with four different substituents, then this carbon atom is asymmetric and the molecule, with rare exceptions (see 7.1.3), is chiral. So, of the two alcohols - propanol-2 and butanol-2 - the first is achiral (two CH 3 groups at the C-2 atom), and the second is chiral, since in its molecule at the C-2 atom all four substituents are different ( H, OH, CH 3 and C 2 H 5). An asymmetric carbon atom is sometimes marked with an asterisk (C*).

Therefore, the butanol-2 molecule is able to exist as a pair of enantiomers that do not combine in space (Fig. 7.2).

Rice. 7.2.Enantiomers of chiral molecules of butanol-2 do not combine

Properties of enantiomers. Enantiomers have the same chemical and physical properties (melting and boiling points, density, solubility, etc.), but exhibit different optical activity, i.e., the ability to deflect the plane of polarized light*.

When such light passes through a solution of one of the enantiomers, the plane of polarization deviates to the left, the other - to the right by the same angle α. The value of the angle α reduced to standard conditions is the constant of the optically active substance and is called specific rotation[α]. Left rotation is denoted by a minus sign (-), right rotation is indicated by a plus sign (+), and enantiomers are called left and right rotation, respectively.

Other names of enantiomers are associated with the manifestation of optical activity - optical isomers or optical antipodes.

Each chiral compound can also have a third, optically inactive form - racemate. For crystalline substances, this is usually not just a mechanical mixture of crystals of two enantiomers, but a new molecular structure formed by the enantiomers. Racemates are optically inactive because the left rotation of one enantiomer is compensated by the right rotation of an equal amount of the other. In this case, a plus-minus sign (?) is sometimes placed before the name of the connection.

7.1.2. Relative and absolute configurations

Fisher projection formulas. Stereochemical formulas can be used to depict configurational isomers on a plane. However, it is more convenient to use simpler Fisher projection formulas(easier - Fisher projections). Let us consider their construction using lactic (2-hydroxypropanoic) acid as an example.

The tetrahedral model of one of the enantiomers (Fig. 7.3) is placed in space so that the chain of carbon atoms is in a vertical position, and the carboxyl group is on top. Bonds with non-carbon substituents (H and OH) at the chiral center should

* See tutorial for details Remizov A.N., Maksina A.G., Potapenko A.Ya. Medical and biological physics. 4th ed., revised. and additional - M.: Bustard, 2003.- S. 365-375.

Rice. 7.3.Construction of the Fischer projection formula of (+)-lactic acid

us to be directed towards the observer. After that, the model is projected onto a plane. In this case, the symbol of the asymmetric atom is omitted; it is understood as the point of intersection of the vertical and horizontal lines.

The tetrahedral model of a chiral molecule before projection can be placed in space in different ways, not only as shown in Fig. 7.3. It is only necessary that the links that form a horizontal line on the projection be directed towards the observer, and the vertical links - beyond the plane of the picture.

The projections obtained in this way can, with the help of simple transformations, be brought to a standard form in which the carbon chain is located vertically, and the senior group (in lactic acid this is COOH) is on top. Transformations allow two operations:

In the projection formula, it is allowed to interchange any two substituents at the same chiral center an even number of times (two permutations are enough);

The projection formula can be rotated in the plane of the figure by 180? (which is equivalent to two permutations), but not by 90?.

D.L-Configuration designation system. At the beginning of the twentieth century. a classification system for enantiomers was proposed for relatively simple (in terms of stereoisomerism) molecules, such as α-amino acids, α-hydroxy acids, and the like. Behind configuration standard glyceraldehyde was taken. Its levorotatory enantiomer was arbitrarily formula (I) is assigned. This configuration of the carbon atom was designated by the letter l (from lat. laevus- left). The dextrorotatory enantiomer was accordingly assigned formula (II), and the configuration was designated by the letter d (from Lat. dexter- right).

Note that in the standard projection formula l -glyceraldehyde group OH is on the left, and at d -glyceraldehyde - on the right.

Assignment to d- or l - a number of other structurally related optically active compounds is produced by comparing the configuration of their asymmetric atom with the configuration d- or l -glyceraldehyde. For example, in one of the enantiomers of lactic acid (I) in the projection formula, the OH group is on the left, as in l -glyceraldehyde, so the enantiomer (I) is referred to as l -row. For the same reasons, the enantiomer (II) is assigned to d -row. Thus, from a comparison of the Fisher projections, we determine relative configuration.

It should be noted that l -glyceraldehyde has a left rotation, and l -lactic acid - right (and this is not an isolated case). Moreover, the same substance can be both left-handed and right-handed, depending on the determination conditions (different solvents, temperature).

The sign of the rotation of the plane of polarized light is not related to belonging to d- or l -stereochemical series.

The practical determination of the relative configuration of optically active compounds is carried out using chemical reactions: either the test substance is converted into glyceraldehyde (or another substance with a known relative configuration), or, conversely, from d- or l -glyceraldehyde, the test substance is obtained. Of course, in the course of all these reactions, the configuration of the asymmetric carbon atom should not change.

Arbitrary assignment of conditional configurations to left- and right-handed glyceraldehyde was a forced step. At that time, the absolute configuration was not known for any chiral compound. The establishment of the absolute configuration became possible only thanks to the development of physicochemical methods, especially X-ray diffraction analysis, with the help of which in 1951 the absolute configuration of a chiral molecule was determined for the first time - it was a salt of (+)-tartaric acid. After that, it became clear that the absolute configuration of d- and l-glyceraldehydes is indeed the same as was originally attributed to them.

d,l-System is currently used for α-amino acids, hydroxy acids and (with some additions) for carbohydrates

(see 11.1.1).

R,S-Configuration designation system. The d,L-System is of very limited use, since it is often impossible to assign the configuration of any compound to glyceraldehyde. The universal system for designating the configuration of centers of chirality is the R,S-system (from lat. rectus- straight, sinister- left). It is based on sequence rule, based on the seniority of the substituents associated with the center of chirality.

The seniority of the substituents is determined by the atomic number of the element directly associated with the center of chirality - the larger it is, the older the substituent.

Thus, the OH group is older than NH 2, which, in turn, is older than any alkyl group and even COOH, since in the latter a carbon atom is bonded to the asymmetric center. If the atomic numbers turn out to be the same, the group is considered to be the eldest, in which the atom following the carbon has a higher serial number, and if this atom (usually oxygen) is double bonded, it is counted twice. As a result, the following groups are arranged in descending order of precedence: -COOH > -CH=O > -CH 2 OH.

To determine the configuration, the tetrahedral model of the compound is placed in space so that the smallest substituent (in most cases, this is a hydrogen atom) is the furthest away from the observer. If the seniority of the other three substituents decreases clockwise, then the R-configuration is assigned to the center of chirality (Fig. 7.4, a), if counterclockwise -S- configuration (see Fig. 7.4, b), as seen by the driver behind the wheel (see Fig. 7.4, V).

Rice. 7.4.Determination of the configuration of enantiomers of lactic acid by R,S- system (explanation in text)

Fisher projections can be used to designate a configuration according to the RS-system. To do this, the projection is transformed so that the junior deputy is located on one of the vertical links, which corresponds to its position behind the plane of the drawing. If, after the projection transformation, the seniority of the remaining three substituents decreases clockwise, then the asymmetric atom has the R-configuration, and vice versa. The use of this method is shown on the example of l-lactic acid (numbers indicate the seniority of the groups).

There is an easier way to determine the R- or S-configuration according to the Fisher projection, in which the junior substituent (usually an H atom) is located on one of horizontal connections. In this case, the above permutations are not carried out, but the seniority of the substituents is immediately determined. However, since the H atom is “out of place” (which is equivalent to the opposite configuration), a drop in precedence will now mean not an R-configuration, but an S-configuration. This method is shown on the example of l-malic acid.

This method is especially convenient for molecules containing several chiral centers, when permutations would be required to determine the configuration of each of them.

There is no correlation between the d,l and RS systems: these are two different approaches to designating the configuration of chiral centers. If in the d,L-system, compounds similar in configuration form stereochemical series, then in the RS-system, chiral centers in compounds, for example, of the l-series, can have both R- and S-configurations.

7.1.3. diastereomerism

Diastereomers are called stereoisomers that are not related to each other, like an object and an incompatible mirror image, that is, not being enantiomers.

The most important groups of diastereomers are σ-diastereomers and π-diastereomers.

σ -Diastereomers. Many biologically important substances contain more than one center of chirality in the molecule. In this case, the number of configurational isomers increases, which is defined as 2 n , where n is the number of centers of chirality. For example, in the presence of two asymmetric atoms, the compound can exist as four stereoisomers (2 2 = 4) that make up two pairs of enantiomers.

2-Amino-3-hydroxybutanoic acid has two centers of chirality (C-2 and C-3 atoms) and therefore must exist as four configurational isomers, one of which is a natural amino acid.

Structures (I) and (II), corresponding to l- and d-threonine, as well as (III) and (IV), corresponding to l- and d-allotreonine (from the Greek. alios- the other), relate to each other as an object and an incompatible mirror image, i.e. they are pairs of enantiomers. Comparison of structures (I) and (III), (I) and (IV), (II) and (III), (II) and (IV) shows that in these pairs of compounds, one asymmetric center has the same configuration, while the other is the opposite. These pairs of stereoisomers are diastereomers. Such isomers are called σ-diastereomers, since the substituents in them are linked to the center of chirality by σ-bonds.

Amino acids and hydroxy acids with two centers of chirality are classified as d- or l -series according to the configuration of the asymmetric atom with the smallest number.

Diastereomers, unlike enantiomers, differ in physical and chemical properties. For example, l-threonine, which is part of proteins, and l-allotreonine have different values of specific rotation (as shown above).

Meso compounds. Sometimes a molecule contains two or more asymmetric centers, but the molecule as a whole remains symmetrical. An example of such compounds is one of the stereoisomers of tartaric (2,3-dihydroxybutanedioic) acid.

Theoretically, this acid, which has two centers of chirality, could exist in the form of four stereoisomers (I)-(IV).

Structures (I) and (II) correspond to the enantiomers of the d- and l-series (the assignment was made according to the "upper" center of chirality). It might seem that structures (III) and (IV) also correspond to a pair of enantiomers. In fact, these are formulas of the same compound - optically inactive mesotartaric acid. It is easy to verify the identity of formulas (III) and (IV) by turning formula (IV) by 180? without taking it out of the plane. Despite the two centers of chirality, the mesotartaric acid molecule as a whole is achiral, since it has a symmetry plane passing through the middle of the C-2-C-3 bond. With respect to d- and l-tartaric acids, mesotartaric acid is a diastereomer.

Thus, there are three (not four) stereoisomers of tartaric acids, not counting the racemic form.

When using the R,S system, there are no difficulties in describing the stereochemistry of compounds with several chiral centers. To do this, determine the configuration of each center according to the R,S-system and indicate it (in brackets with the corresponding locants) before the full name. Thus, d-tartaric acid will receive the systematic name (2R,3R)-2,3-dihydroxybutanedioic acid, and mesotartaric acid will have the stereochemical symbols (2R,3S)-.

Like mesotartaric acid, there is a mesoform of the α-amino acid cystine. With two centers of chirality, the number of stereoisomers of cystine is three due to the fact that the molecule is internally symmetrical.

π -Diastereomers. These include configurational isomers containing a π-bond. This type of isomerism is typical, in particular, for alkenes. With respect to the π-bond plane, the same substituents on two carbon atoms can be located one at a time (cis) or at different (trance) sides. In this regard, there are stereoisomers known as cis- And trance-isomers, as shown in the case of cis- and trans-butenes (see 3.2.2). π-Diastereomers are the simplest unsaturated dicarboxylic acids - maleic and fumaric.

Maleic acid is thermodynamically less stable cis-isomer compared to trance-isomer - fumaric acid. Under the action of certain substances or ultraviolet rays, an equilibrium is established between both acids; when heated (~150 ?C), it is shifted towards a more stable trance-isomer.

7.2. Conformations

Around a simple C-C bond, free rotation is possible, as a result of which the molecule can take various forms in space. This can be seen in the stereochemical formulas of ethane (I) and (II), where the CH groups marked in color 3 located differently relative to another CH group 3.

Rotation of one CH group 3 relative to the other occurs without breaking the configuration - only the relative position in space of hydrogen atoms changes.

The geometric shapes of the molecule, passing into each other by rotation around σ-bonds, are called conformations.

According to this conformational isomers are stereoisomers, the difference between which is caused by the rotation of individual sections of the molecule around σ-bonds.

Conformational isomers usually cannot be isolated in an individual state. The transition of different conformations of the molecule into each other occurs without breaking bonds.

7.2.1. Conformations of acyclic compounds

The simplest compound with a C-C bond is ethane; consider two of its many conformations. In one of them (Fig. 7.5, a) the distance between the hydrogen atoms of two CH groups 3 the smallest, so the C-H bonds that are opposite each other repel each other. This leads to an increase in the energy of the molecule and, consequently, to a lower stability of this conformation. When looking along the C-C bond, it is seen that the three C-H bonds at each carbon atom “overshadow” each other in pairs. This conformation is called obscured.

Rice. 7.5.obscured (a, b) and inhibited (in, G) ethane conformations

In another conformation of ethane, which occurs upon rotation of one of the CH groups 3 at 60? (see Fig. 7.5, c), the hydrogen atoms of the two methyl groups are as far apart as possible. In this case, the repulsion of the electrons of the C-H bonds will be minimal, and the energy of such a conformation will also be minimal. This more stable conformation is called inhibited. The difference in the energy of both conformations is small and amounts to ~12 kJ/mol; it defines the so-called energy barrier of rotation.

Newman's projection formulas. These formulas (more simply, Newman projections) are used to depict conformations on a plane. To construct a projection, the molecule is viewed from the side of one of the carbon atoms along its bond with the neighboring carbon atom, around which rotation takes place. When projecting, three bonds from the carbon atom closest to the observer to hydrogen atoms (or, in the general case, to other substituents) are arranged in the form of a three-beam star with angles of 120?. The (invisible) carbon atom removed from the observer is depicted as a circle, from which it is also at an angle of 120? three connections go. Newman projections also give a visual representation of the eclipsed (see Fig. 7.5, b) and hindered (see Fig. 7.5, d) conformations.

Under normal conditions, ethane conformations easily transform into each other, and one can speak of a statistical set of different conformations that differ insignificantly in energy. It is impossible to single out even a more stable conformation in an individual form.

In more complex molecules, the replacement of hydrogen atoms at neighboring carbon atoms with other atoms or groups leads to their mutual repulsion, which affects the increase in potential energy. So, in the butane molecule, the eclipsed conformation will be the least favorable, and the hindered conformation with the most distant CH 3 groups will be the most advantageous. The difference between the energies of these conformations is ~25 kJ/mol.

As the carbon chain lengthens in alkanes, the number of conformations rapidly increases as a result of the expansion of the possibilities of rotation around each C-C bond, so the long carbon chains of alkanes can take many different forms, for example, zigzag (I), irregular (II) and pincer (III ).

A zigzag conformation is preferred, in which all C-C bonds in the Newman projection form an angle of 180°, as in the staggered conformation of butane. For example, fragments of long-chain palmitic C 15 H 31 COOH and stearic C 17 H 35 COOH acids in a zigzag conformation (Fig. 7.6) are part of the lipids of cell membranes.

Rice. 7.6.Skeletal formula (a) and molecular model (b) of stearic acid

In the pincer conformation (III), carbon atoms that are distant from each other in other conformations approach each other. If functional groups, such as X and Y, are at a sufficiently close distance, capable of reacting with each other, then as a result of an intramolecular reaction this will lead to the formation of a cyclic product. Such reactions are quite widespread, which is associated with the advantage of the formation of thermodynamically stable five- and six-membered rings.

7.2.2. Conformations of six-membered rings

The cyclohexane molecule is not a flat hexagon, since with a flat structure the bond angles between carbon atoms would be 120°, i.e., they would significantly deviate from the normal bond angle of 109.5°, and all hydrogen atoms were in an unfavorable eclipsed position. This would lead to cycle instability. In fact, the six-membered cycle is the most stable of all cycles.

The various conformations of cyclohexane result from partial rotation around σ bonds between carbon atoms. Of several non-planar conformations, the most energetically favorable is the conformation armchairs(Fig. 7.7), since in it all the bond angles between the C-C bonds are ~110?, and the hydrogen atoms at neighboring carbon atoms do not obscure each other.

In a non-planar molecule, one can only conditionally speak of the arrangement of hydrogen atoms "above and below the plane." Instead, other terms are used: bonds directed along the vertical axis of symmetry of the cycle (in Fig. 7.7, A shown in color), called axial(a), and bonds oriented from the cycle (as if along the equator, by analogy with the globe) are called equatorial(e).

In the presence of a substituent in the ring, the conformation with the equatorial position of the substituent is more favorable, such as, for example, conformation (I) of methylcyclohexane (Fig. 7.8).

The reason for the lower stability of conformation (II) with the axial arrangement of the methyl group is 1,3-diaxial repulsion CH groups 3 and H atoms in positions 3 and 5. In this

Rice. 7.7.Cyclohexane in chair conformation:

A- skeletal formula; b- ball-and-stick model

Rice. 7.8.Cycle inversion of a methylcyclohexane molecule (not all hydrogens shown)

case, the cycle is subjected to the so-called inversions, adopting a more stable conformation. The repulsion is especially strong in cyclohexane derivatives having positions 1 and 3 of the bulk groups.

In nature, there are many derivatives of the cyclohexane series, among which six-hydric alcohols play an important role - inositols. Due to the presence of asymmetric centers in their molecules, inositols exist in the form of several stereoisomers, of which the most common is myoinositis. The myoinositol molecule has a stable chair conformation in which five of the six OH groups are in equatorial positions.

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Moscow: Laboratory of Knowledge

The textbook on organic chemistry contains terms, concepts and designations arranged in alphabetical order used to describe molecules and processes with their participation. Much attention is paid to the stereochemical aspects of the structure of molecules, the relationship between the structure and reactivity, the mechanisms of chemical reactions, including nominal ones.

Seniority is determined by the rules of successive seniority of deputies (see).<...>Rules for the successive precedence of deputies.<...>The seniority of substituents is determined as follows: 1) An atom associated with a chiral center with a large<...>Other examples of relative seniority of substituents: –CH2OH –COOH; CH2NH2 substituent seniority relative to one asymmetric

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Organic chemistry. Part I, II studies. allowance

Moscow: Prometheus Publishing House

This study guide is the first book (of three) to include updated content covering all major classes of acyclic hydrocarbons in the alpha series. The book contains up-to-date data on nomenclature and isomerism, electronic structure, including quantum-chemical concepts, on the methods of obtaining and characteristic chemical properties of organic compounds, as well as illustrations of the biological role of derivatives of organic substances of the corresponding class. Particular attention is paid to modern theoretical concepts in organic chemistry, the relationship between the structure of compounds and reactivity, as well as reaction mechanisms that explain the features of chemical behavior. The methodical design of the manual serves the purpose of optimizing the educational process and increasing its effectiveness.

<...> <...> <...>Decreasing seniority of the remaining three substituents clockwise indicates the R-configuration, against<...>In this case, the decreasing order of precedence of substituents 1-III clockwise means the S-configuration, against

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No. 5 [Military History Journal, 2007]

One of von Braun's deputies.<...>From April 1945 he was deputy commander of the 4th Ukrainian Front.<...>Since 1946 he was deputy commander of the air army, in 1947-1949. Deputy Head of the State<...>Since 1952, Deputy, First Deputy Chief of the General Staff of the Air Defense Forces of the country for a special<...>Miranovich (deputy chief editor of the Krasnaya Zvezda newspaper), D.P.

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No. 4 [Posev, 1980]

Socio-political magazine. Published since November 11, 1945, published by the publishing house of the same name. The motto of the magazine is "God is not in power, but in truth" (Alexander Nevsky). The periodicity of the journal has changed. Initially published as a weekly publication, for some time it was published twice a week, and from the beginning of 1968 (number 1128) the magazine became a monthly one.

called détente, we were faced with the strengthening of the Soviet military machine, we got acquainted with the “armies of deputies

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The article discusses the structure of the European Court of Human Rights, its features, functions and methods of dispute resolution, as well as the historical aspect of the development of the European Court system itself and the reasons for its reorganization. According to the author, this development has a beneficial effect on the work of the European Court. By applying the Additional Protocols to the Convention for the Protection of Human Rights and Fundamental Freedoms, the Court itself noticeably improves its activities and opens up more opportunities for resolving disputes. With the innovations introduced, the Court began to consider complaints more and make reasoned decisions. The author believes that the European Court will develop and improve for a long time to achieve all hidden potentialities, but the main goal of the European Court remains the protection of human rights and fundamental freedoms.

It should be noted that in the European Court there is a distribution of judges by seniority, so after<...>Chairman, Vice-Chairmen and Chairmen of Sections, seniority is determined by the date of election<...>The seniority of judges with the same tenure is determined by age.<...>At Plenary Sessions, the Court elects for a period of three years the President of the Court and two Vice-Presidents<...>It is composed of the President of the Court, the Vice-President of the Court and the Presidents of the Sections.

The article deals with the problems of chinoproizvodstvo in the Russian army from the beginning of the XVIII century to 1917. The author, relying on the regulatory documents of those years, shows the historical and legal aspects and features of various systems of rank production, analyzes their advantages and disadvantages in matters of conferring regular military ranks on officers and promotion in military positions

Andrey Mikhailovich - Acting State Counselor of Justice of the Russian Federation, 3rd class, Deputy<...>Nevertheless, Peter I spoke extremely negatively about the practice of promotion in ranks by seniority, which existed<...> <...> <...>Generals who were promoted to the rank for outstanding distinction had an advantage in seniority over generals.

Structure and properties of hydrocarbons Guidelines

The guidelines were developed as a course of lectures on the discipline Organic Chemistry and Fundamentals of Biochemistry (Part I, hydrocarbons) for students of the correspondence department of IGHTU studying in the specialties 240202 Chemical technology and equipment for finishing production, 240201 - Technology and equipment for the production of chemical fibers and composite materials based on them and 240501 Chemical Technology of Macromolecular Compounds (CTPM), include assignments for test No. 1 and recommendations for its implementation.

<...> <...>arrange groups, S-isomer R-isomer H C2H5 H3C C3H7 H7C3 CH3 H C2H5 associated with it, in descending order of precedence<...> <...>deputy .

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No. 12 [Court cases of the European Court, 2018]

The precedents of the European Court of Human Rights is a mass media that is created and developed in electronic form. The publication publishes a large volume of legal texts, introducing documents of the Council of Europe and, above all, the European Court of Human Rights into practical and scientific circulation. The journal publishes in translation into Russian the texts of judgments, as well as precedent decisions (decisions on the inadmissibility of complaints with a reasoning part) of the European Court of Human Rights on complaints against the Russian Federation, the most important (in the opinion of the Court itself) judicial acts on complaints against other states - Parties to the Convention, official documents of the Committee of Ministers of the Council of Europe concerning the execution of judgments of the European Court, as well as the most interesting documents of other bodies and structures of the Council of Europe (PACE, SEPEJ, ECRI and others), all together forming the "law of the Council of Europe". At the same time, the main attention is paid to the documents of the European Court of Human Rights as the most important from a practical point of view for Russian law enforcers.

Election of the President of the Court and Vice-Presidents of the Court, Section Presidents and Vice-Presidents<...>RULE 53 Seniority 1.<...> <...> <...>RULE 10 Duties of the Vice-Presidents of the Court The Vice-Presidents of the Court shall assist

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No. 6 [Refrigeration technology, 2017]

The only scientific-technical and informational-analytical monthly magazine in Russia and the CIS countries on scientific and technical developments in all areas of refrigeration, cryogenic equipment and technology, air conditioning and ventilation, automation and control, refrigerated transport, food production processes and apparatus, working substances, problems of ecology and energy saving. For more than 100 years, the journal has been the primary source of information on fundamental and applied work of leading domestic and foreign scientists, as well as a publication for publishing the results of dissertations for the degree of candidate and doctor of science. The journal is included in the international abstract database Agris, is registered in the Russian Science Citation Index (RSCI).

opposite sides of this double bond, which obeys the Cahn–Ingold–Prelog rule (the rule of precedence<...>This distribution is subject to the Cahn-Ingold-Prelog rule (sometimes called the “priority rule”).<...>The higher the atomic number of that atom, the older the substituent.<...>The deputy is considered senior in whose favor the first difference will be.<...>If the seniority of the substituents cannot be determined by the atoms of the second layer, the comparison is carried out by atoms

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Theory of diplomacy

VSU Publishing House

The manual "Theory of Diplomacy" was prepared for students of Voronezh State University (Russian Federation). It includes both cognitive and practical aspects.

Seniority of diplomatic workers.<...>Diplomatic ranks and seniority among diplomats.<...>VICE-CONSUL - the rank (class) of a consul who heads the vice-consulate in the host country or is a deputy<...>printed on special paper, certified with a seal and countersigned by the Minister of Foreign Affairs or his deputy<...>: collective seniority of the diplomatic corps invited to a public event; seniority

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Organic chemistry. At 4 h. Ch. 2 tutorial

Moscow: Laboratory of Knowledge

The textbook systematically describes organic compounds by class, and also outlines the main theoretical provisions of organic chemistry. The structure and properties of organic compounds are considered from the positions of both the theory of electronic displacements and the theory of molecular orbitals. The second part includes chapters on stereochemistry, nucleophilic substitution and elimination reactions, as well as the chemistry of alcohols, thiols, ethers and sulfides, free radicals, and the concept of aromaticity is introduced.

The seniority of the most frequently occurring substituents can be determined from Table. 8.2, in which the conditional<...>Substituents at each end of a multiple bond must be considered separately when establishing precedence.<...>If substituents with higher seniority are located on the same side of the double bond<...>substituents, and the change in precedence as a result of the substitution of one of the groups does not necessarily coincide<...>substituents, and the change in precedence as a result of the substitution of one of the groups does not necessarily coincide

Preview: Organic chemistry. At 4 h. Part 2 (1).pdf (0.2 Mb)

The procedure for consideration of complaints in the European Court of Human Rights

M.: Statute

The second book provides a detailed commentary on the Rules of the European Court of Human Rights (as amended, which entered into force on May 1, 2013), which governs the operation of the Court. The commentary explains the various aspects of this procedure, related to the decision of single judges, Committees, Chambers and the Grand Chamber of the Court of questions regarding the admissibility of individual complaints and the merits, the payment of just satisfaction, the possibility of using amicable settlement (settlement agreement), etc., those. clarifications are given regarding practical issues that arise for citizens and organizations when applying to the European Court of Human Rights. For the convenience of readers, comments are given on the chapters of the Regulations.

After the President of the Court, the Vice-Presidents of the Court and the Presidents of the Sections, the order of precedence of the elected<...>The seniority of Vice-Presidents of the Court, elected to office on the same day, is established<...>Thus,afterthe Presidentof the Court,<...>the first<...>The need

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Organic chemistry. [At 6 o'clock]. Ch. I, II; Part III, IV; Part V, VI [set] studies. allowance

This publication consists of three books (parts I - VI) of the textbook for the course "Organic Chemistry". The first book (Parts I and II) includes updated content covering all major classes of acyclic hydrocarbons of the alpha series. The second book covers the main classes of functional (part III) and heterofunctional (part IV) derivatives of aliphatic hydrocarbons. Parts V and VI of the textbook cover compounds of the cyclic series and include modern data on nomenclature and isomerism, electronic structure, methods of preparation and characteristic chemical properties of the class of alicyclic hydrocarbons (cycloalkanes), aromatic compounds, as well as heterocyclic compounds with one or more heteroatoms in the cycle.

The R-,� S-system is based on the determination of the precedence of the four substituents at the asymmetric atom<...>Determination of R and S-configurations by the rule of seniority of substituents Seniority is determined by atomic numbers<...>ISOMERIA Thus, as a result of the comparison, the following order of precedence of substituents is revealed<...>Substituents are listed in order of precedence.<...>(taking into account the seniority of deputies).

Preview: Organic Chemistry Parts I-VI (1).pdf (2.6 Mb)
Preview: Organic Chemistry Parts I-VI (3).pdf (1.0 Mb)
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Customs diplomacy textbook. allowance

M.: Publishing House of the Russian Customs Academy

The textbook outlines the main theoretical issues of diplomacy and diplomatic relations, identifies the role and place of customs diplomacy, gives its characteristics as a special tool for the implementation of international customs cooperation; the ratio of the foreign policy of the state, international relations, international customs cooperation, diplomacy and customs diplomacy is determined.

Congress also determined the categories of diplomatic representatives, including the issue of seniority<...>class, namely: the class of ambassadors and nuncios, the class of envoys and internuncios, the class of chargé d'affaires. seniority<...>representations, due to their belonging to a particular class, should be carried out only in relation to seniority<...>to which the heads of missions should belong is determined by agreement between the states. seniority<...>heads of missions, changes that do not involve a change in class do not affect his seniority

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In the work, the authors analyze various types of parliamentary activity not only in the Russian Federation, but also in a number of foreign countries. Various options for improving parliamentary activity in modern Russia are proposed

In the United States, the following measures can be applied to a parliamentarian: deprivation of a word; deprivation of the status of "seniority<...>"("system of precedence" means the order in which a privileged position, first of all a right<...>11 the jurisdiction of the Federation Council includes the appointment and dismissal of the first deputy<...>Attorney General and his deputies.<...>The issue of dismissal of the Deputy Chairman of the Accounts Chamber, auditors is being considered

No. 10 [Moscow Journal. History of the Russian State, 2008]

The journal was founded in 1791 by N. M. Karamzin and resumed in 1991. This is a literary, artistic, local history publication of the Moscow Government. Frequency - 1 issue per month. Circulation - 5000 copies. The magazine is one of the few publications that exclusively covers the events of the past and present of Russia on the basis of documentary facts. It reflects all spheres of Russian life in their past and present, publishes unique documents from public and private archives, local history articles, memoirs, biographical essays on the most prominent figures of Russian statehood, science and culture. The publication has general social tasks focused on the formation of the cultural image of a citizen. The historical and local history material published in the journal enhances and educates such socially significant feelings as patriotism, love for the Motherland, responsibility for its fate, humanism, and generally improves the image of state authorities and administration. The authors of the magazine, which is addressed to both specialists and a wide range of readers, are well-known historians, archivists, local historians. The readers of the magazine are people of various ages and professions. For promotion of high ethical and moral principles, the journal was awarded the Distinction of the exhibition "Press-2006", "Press-2007" - "The Golden Fund of the Press". It is recommended to Russian libraries for acquisition of collections. Over the years, the editors have prepared and published special issues dedicated to the anniversaries of certain cities or regions of the Russian Federation. We invite you to take part in a joint project to issue a magazine issue, which will be fully or partially dedicated to the anniversary of your museum.

Head of Administration of the Serebryano-Prudsky Municipal District Vladimir Vladimirovich Melnikov, Deputy<...>The first deputy head of the administration of the Serebryano-Prudsky municipal district Vladimir Vladimirovich came<...>However, his deputy, Gennady Krasnikov, gloomily, as if he was leading a feast during the plague, exclaimed:<...>pp. 26–27. 13 Lists of majors by seniority for 1840. SPb., 1840.<...>P.137. 14 Lists of lieutenant colonels by seniority for 1846. SPb., 1846.

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Fundamentals of bioorganic chemistry [proc. allowance]

M.: FLINTA

The textbook outlines the basics of bioorganic and organic chemistry, discusses the main classes and nomenclature of organic compounds, shows the structural features and properties of organic substances important in biochemical processes - carbohydrates, lipids, amino acids, peptides, proteins and nucleic acids.

the parent structure of the compound. the senior functional group is determined taking into account the relative seniority<...>Table 3 order of precedence of functional groups and their designation in the name of an organic compound<...>in alphabetical order before the name of the parent structure. position of functional groups, substituents<...>the following organic compound: CH C CH2 C COOH CH3 CH2 CH3 CH3 OH 1 2 3 4 5 6 7 1. according to the precedence table<...>(these substituents are -n, -cH2OH, -OH, and -CHO). for glyceraldehyde, two forms are possible

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No. 6 [Bulletin of the European Court of Human Rights, 2016]

The Bulletin of the European Court of Human Rights is the only publication in Russia that publishes a complete translation into Russian of the official Bulletin of the European Court of Human Rights. At the initiative of the Commissioner of the Russian Federation at the European Court of Human Rights, each issue of the journal publishes the full texts of judgments and decisions adopted on complaints against the Russian Federation. The choice of the rulings published in the issue is dictated by the importance of the legal positions set out in them for national judicial practice and the wishes of our readers. In addition to the texts of judicial acts, the journal contains analytical materials, statistical data and author's articles on the problems of the law of the Council of Europe and the European Court of Human Rights.

Rule 52 Seniority 1.<...>The seniority of Vice-Presidents of the Court, elected to office on the same day, is established<...>in accordance with the order of precedence set out in Rule 5.<...>Rule 10 Duties of the Vice-Presidents of the Court The Vice-Presidents of the Court shall assist<...>Rule 11 Replacement of the President of the Court and Vice-Presidents of the Court If the President of the Court and Vice-Presidents

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The article tells about the creation of the Kazan infantry cadet school, its work from 1866 to 1909, the organization of the educational process and final exams. The names of a number of heads of the school and data on its most famous graduates are given.

To the table, at which the head of the school and the class inspector are sitting, those called by the seniority of the list approach<...>The first sacrifices his seniority and is reduced by twenty people in order, together with a friend, to choose<...>From 1931 - Chief of Staff of the Red Army, from 1935 - Chief of the General Staff; in 1937-1938 - first Deputy<...>In 1900 he was appointed head of the Riga police, in 1905 - deputy head of the St. Petersburg detective

No. 4 [Military History Journal, 2008]

Monthly popular scientific publication of the Ministry of Defense of the Russian Federation. It covers topical issues of domestic and foreign military history, the military policy of the Russian state at all stages of its formation and development, the historical experience of ensuring national security, the history of the development of military science and technology, the activities of outstanding Russian and Soviet commanders and naval commanders, as well as many other aspects of military history and science. The readers of the journal are professional historians, specialists from research institutions, faculty, officers and cadets of military educational institutions, veterans of the Great Patriotic War and the Armed Forces, as well as all those who are interested in military history. The publication will also be of interest to the younger generation, as it contains the section "Youth military history magazine". In addition to articles, it publishes cryptograms, chainwords and crosswords on military-historical topics. The authors of the publication are three candidates of sciences, one honored cultural worker of Russia, as well as military experts and historians. This guarantees a high professional level of the content of the journal, consisting of such headings as "Military Symbols", "Military Heraldic Work", "Family Archive", "Symbols of the Russian Empire", "Through the Pages of Rare Editions", "Bookshelf of a Military Historian" , "Criticism and Bibliography", "Memorable Dates" and others. In addition, the journal publishes information on the results of historical research, as well as reports on thematic exhibitions and expositions held by archives and museums. The Military Historical Journal has been published from August 1939 to the present with some interruption: its publication was temporarily discontinued with the outbreak of the Great Patriotic War and resumed already in 1959. Four years ago, a special supplement of the journal appeared on the Internet - Military Historical magazine. Internet Application". Its main task is the publication of articles, documents and scientific research that cannot be placed in a printed edition due to the limited volume of the journal - 80 pages and 8 color pages. Currently, the publication is actively cooperating with educational institutions, and also organizes visiting and correspondence reader conferences, seminars and round tables.

So, in the decree of April 14, 1714, it was determined that all officers occupied vacancies by seniority.<...>However, seniority was taken into account in the production of other officer ranks.<...>Minich, the further compilation of all-army lists by seniority was canceled9.<...>This act determined "not to produce anyone by seniority."<...>And his deputy English general G.

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Basic course of organic chemistry

Ivanovo State University of Chemical Technology

The textbook contains the main theoretical provisions of the course of lectures on the discipline of Organic Chemistry and the basics of biochemistry, the control task and recommendations for its implementation. Recommended by the educational and methodological association for education in the field of chemical technology and biotechnology as a teaching aid for students of higher educational institutions studying in the areas of Chemical technology and Energy and resource-saving processes in chemical technology, petrochemistry and biotechnology.

These substituents are named in order of precedence (from less complex to more complex).<...>Divalent substituents are called by replacing the suffix -an with -ylidene (the exception is the substituent methylene<...>an asymmetric atom in a molecule and arrange the groups associated with it in order of S-isomer R-isomer in descending order of precedence<...>Rotation from it through the next most senior deputy (C2H5-) to the youngest (CH3-) passes<...>deputy .

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The twelfth issue of the Almanac of the St. Philaret Orthodox Christian Institute includes articles on biblical studies, theology and liturgy.

Kroshkina Hierarchism and Seniority in the Writings of the Apostolic Men O.V.<...>A somewhat distorted image of the bishop arises as, first of all, the high priest and substitute for Christ<...>If we distinguish between the concepts of seniority and hierarchy, then by seniority we mean<...>in the writings of the apostolic men 63 and the substitute of Christ, then in the church there is no need for search, creativity<...>the majority of parishioners read prayer books more often than the Gospel,” testifies hegumen Evfimy (Moiseev), deputy

Fundamentals of organic chemistry textbook. allowance

Moscow: Laboratory of Knowledge

The educational publication, written by teachers of the Department of Organic Chemistry, Faculty of Chemistry, Moscow State University, outlines a short course in organic chemistry, including information about the structure, methods of preparation, properties and applications of the main classes of organic compounds. The features of the mechanisms of the most important organic reactions (nucleophilic substitution, elimination, etc.) are considered. The necessary information about the modern most informative physicochemical methods for studying organic compounds (mass spectrometry, NMR spectroscopy, IR spectroscopy, etc.) is given.

If the substituent atoms of the ethylene unit are the same, then the determination of seniority should be done according to "<...>For example, ethyl, vinyl and acetylene groups are arranged in order of precedence in the following row: CH3CH2<...>− (ССНН) precedence of oxygen-containing groups<...>To designate enantiomers, the R/S nomenclature is adopted, based on the seniority of the substituents.<...>Let the seniority of the substituents change in the following order: a > b > c > d, then the transition from the senior

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Organic chemistry textbook. allowance

The current state of the theory of the structure of organic compounds, methods for determining the structure of organic molecules, the main classes of organic compounds and their reactivity are considered. There are questions for self-control. Rice. 27. Tab. 2. Bibliography: 7 titles.

In the title, indicate the places of the deputies in numbers, name the deputies and indicate their number; 3.<...>In the presence of two substituents of different kinds, the entry of the next substituent into the ring determines the substituent<...>Seniority is determined by atomic numbers - the more, the older.<...>If the group precedence decreases clockwise, then the asymmetric center has an R-configuration.<...>If the seniority of the substituents falls counterclockwise, then this is an S-configuration.

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No. 4 [Accounting and banks, 2013]

One of the leading Russian banking publications. It has been published since 1996. It discusses the organization and maintenance of accounting in credit institutions, their taxation and analysis of the financial condition, the introduction of new technologies, and the legal aspects of banking. Bank statements are published.

The draft Civil Code of the Russian Federation provides for the possibility of transferring the seniority of mortgages (the seniority of mortgages in relation to<...>the right of pledge, seniority according to Copyright OJSC “Central Design Bureau “BIBCOM” & LLC “Agency Book-Service” No. 4’2013 55<...>The transfer of seniority is subject to state registration.<...>within the limits of the amount, the seniority of which is transferred.<...>the terms of the mortgage to which seniority is granted. * * * The project pays special attention to the protection of the rights

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Organic chemistry. Tasks for tests and methods of their solutions. Part 2 studies. allowance

Contains materials of the lecture course, examples of solutions and control tasks in terms of functional derivatives of hydrocarbons. It is intended for self-preparation for practical classes, performance of tests, preparation for tests and exams for students of technological specialties of distance learning, studying the discipline "Organic Chemistry".

Moreover, if the nitrogen atom has substituents , then the position and number of substituents are indicated.<...>Under this system, first determine the precedence, or sequence of substituents associated<...>an asymmetric atom, based on the rules of precedence. 1.<...>If the seniority cannot be determined from the first atoms associated with an asymmetric atom, then the seniority<...>There are no electron donor substituents.

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No. 2 [Military History Journal, 2017]

LANTSOVA (Deputy Executive Secretary of the Editorial Board); E.V. KRIEGER; A.A.<...>It contained a requirement to combine the principles of seniority (length of service<...>True, during this period the seniority in rank was counted, which was assigned to the junkers who distinguished themselves in their studies.<...>The signature of the first deputy commander of the BTiMV Korobkov was important.<...>Deputy Yakov Nikolaevich Fedorenko. Have someone read it."

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The article is devoted to the study of the names of structural units and positions in the organigrams of the State Chancellery of Lower Saxony and the administration of the Governor of the Perm Territory. The purpose of the work is to identify intercultural and interlingual asymmetries in the organigrams of these government structures. The organigram is a visualization of the organizational and personnel structure of the government, it reflects the hierarchy of government departments, indicating the name, position and surname of the head of the department. The organigram is considered as a subtype of indicating orienting texts. The analysis showed that intercultural asymmetry manifests itself at the level of the hierarchical organization of structures of government bodies (a discrepancy between the number of departments and their functional orientation), interlingual asymmetry - at the level of the names of functional subsystems, managerial units and the names of senior positions. Positions equal in status or functionality in the administration of the Governor of the Perm Territory and the State Chancellery of Lower Saxony have been determined, for example: Governor - Prime Minister, Director of the Department of the Perm Territory - Head of the Department in the State Chancellery, Head of the Administration of the Governor of the Perm Territory - Head of the State Chancellery. The results obtained can be used in the training of bachelors and masters of the direction "Linguistics" of the profile "Translation and Translation Studies", "State and Municipal Administration" in order to expand the picture of the world, to ensure adequate communicative behavior during high-level visits

Called to know the basic rules of diplomatic protocol, to have information about protocol seniority<...>Political communication 83 tament and deputy director of the department.<...>When training translators, it is necessary to explain the concept of protocol seniority, to train in translation

Judicial practice of the European Court of Human Rights on Article 10 of the European Convention. T. 1 collection

Media Rights Defense Center

The book presents for the first time translated into Russian selected judgments of the European Court of Human Rights on Article 10 of the European Convention guaranteeing freedom of expression. In this publication, each judgment is accompanied by a brief, informal summary of the case to help navigate the Court's case law.

Rule 5 (Seniority) 1.<...>After the President, Vice-Presidents and Section Presidents, the order of precedence of the elected judges<...>The seniority of Vice-Presidents of the Court, elected to office on the same day, is established<...>In order of precedence ad hoc judges follow the elected judges; their seniority is also determined by<...>Rule 10 (Duties of the Vice-Presidents of the Court) The Vice-Presidents of the Court shall assist

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Estates, public service and governing bodies of the Russian Empire studies. allowance

Sib. feder. university

The manual gives a description of the estates that developed in society during the 18th–19th centuries; the system of military and civil service is considered; the formation and activities of the state administration bodies of the Russian Empire are shown.

By seniority and vacancies, they were also promoted to chief officer ranks.<...>Promotion to colonels was carried out on vacancies by seniority, or outside the rules.<...>Each minister had one or more comrades (deputies) subordinate to him.<...>The department was headed by a director, whose deputy was usually a vice director.<...>Vice director - in 1812-1917. position of deputy director of the department, office of the ministry

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No. 8 [World of Legal Science, 2010]

The journal "World of Legal Science" is included in the new List of peer-reviewed scientific publications in which the main results for the degree of Candidate of Science for the degree of Doctor of Science dated December 1, 2015 No. 13-6518 (number in the List 1614) should be published

Grigonis DEPUTY EDITOR-IN-CHIEF: V.M. Chibinev EDITORIAL ADDRESS: 191187, Moscow<...>The seniority between land and sea ranks was determined as follows: “... who is of the same rank with whom<...>The seniority of production was given great importance.<...>Moreover, the division of the latter by class was preserved, as well as the calculation of seniority by the time of appointment.<...>Deputies V.F.

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Let us analyze the question of seniority of pledges in a more complex situation, namely, when securing the future<...>DEPOSITS FOR FUTURE LIABILITIES The article analyzes the issue of determining seniority<...>Keywords: pledge, seniority, future obligation, registration of notices of pledge of movable property<...>Can B refer to its seniority?<...>IX:–4:101 DCFR, such a delay in creation does not affect the question of precedence.

Paragraph

The material on the main sections of organic chemistry is briefly presented, the main methods of studying organic substances, qualitative reactions, and methods for identifying individual compounds are considered.

Seniority is determined by special rules for the successive precedence of deputies CH 3 CH 2<...>In this case, two ways of arranging substituents at the corners of the tetrahedron are possible.<...>: A E D B B D E A (two permutations of substituents) 3) having fixed one substituent, the other three can be<...>Substituent structure isomerism: propylbenzene isopropylbenzene 2.<...>Isomerism of the number of substituents: ethylbenzene ortho-xylene 2.8.

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Improving the system of labor motivation for hotel staff in Moscow (on the example of the East Gate Hotel)

Checked through the search system of text borrowings

<...> <...> <...> <...>

The article briefly shows the activities of a prominent Soviet naval commander, Admiral L.M. Haller, who was groundlessly repressed in 1948.

explained to Haller about his appointment to the post of chief of the naval forces (namorsi), bypassing the seniority<...>Galler was appointed Deputy Chief of the Naval Forces of the Red Army22.<...>Smirnov-Svetlovsky), as well as the Deputy Commander of the Pacific Fleet, Captain 1st Rank N.G. Kuznetsova.<...>Haller was appointed Deputy People's Commissar for Shipbuilding and Armaments.<...>Kuznetsov, Lev Mikhailovich also practically performed the duties of the First Deputy People's Commissar of the Navy.

Laboratory workshop in organic chemistry

VSU Publishing House

Prepared at the Department of Organic Chemistry, Faculty of Chemistry, Voronezh State University.

Determination of the order of precedence of deputies. Optical isomerism, optical activity.<...>Induction mechanism for transferring the influence of substituents.<...>Qualitative assessment of the strength and direction of the inductive influence of substituents.<...>Conjugated mechanism for transferring the influence of substituents.<...>Qualitative assessment of the strength and direction of mesomeric effects of ±M-substituents.

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The article analyzes the issue of determining the seniority of pledges in the event of securing a future obligation: can the pledgee in advance, before the occurrence of the secured obligation, reserve an advantage for himself in satisfying his claims over other pledgees and whether the answer to the question posed depends on whether the pledge is subject to registration (accounting )? In considering this problem, the author refers, among other things, to foreign experience, which is reflected in the DCFR, the UNCITRAL Legislative Guide on Secured Transactions.

For example, the principle of seniority, on the basis of which the entire system of work motivation in Japan is determined<...>The principle of seniority is also preserved, both in the distribution of social benefits and services, and in determining<...>remuneration depending on the age category of the employee. According to many researchers, the seniority system<...>Preserving the principle of seniority allows you to accurately divide the company's personnel into groups that differ<...>Book-Service” 56 Annex 2 Organizational structure of the hotel “East Gate” General Director Deputy

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#6 [Law, 2015]

The structure of the magazine includes the following headings: Interviews of those who really affect the state of legislation and law enforcement in the country. We ask our guests your questions. Event. Expert comments - the most important events in the country through the eyes of leading lawyers in Russia. News of the legal community - what happened in a month and what to expect tomorrow. Law firms, government agencies, universities, research centers. The theme of the issue is scientific and practical articles by leading scientists and practitioners. Judicial practice - the most important and interesting decisions of arbitration courts and courts of general jurisdiction. Trends and comments. Discussion club - discussion of problematic issues of legislation and practice of its application. Theory and practice - research by our authors on topical legal topics. Foreign experience - analysis of theoretical and practical problems relevant to the Russian legal order that arise in other countries. Articles of foreign researchers and practicing lawyers. Reviews. Reviews - reviews of the most interesting novelties of legal literature and reviews of representatives of legal science.

Deputy

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The article is devoted to the phenomenon of super-seniority, which is still unknown to the Russian legal order: granting a pledgee who finances the acquisition of property an unconditional advantage over other pledgees. With the introduction in Russia of a system for registering notices of pledge of movable property and determining seniority at the time of such registration, if there is a possibility of pledging future things, the issue of super seniority may also be relevant for the domestic legal order. The author analyzes foreign experience, the reasons for granting super seniority to persons financing the acquisition, and also raises the question of the advisability of borrowing a foreign approach by the Russian legislator.

With the introduction in Russia of a system for registering notices of pledge of movable property and determining the seniority<...>With such a rule for determining precedence, there is a need to provide a special<...>If we were to follow the general DCFR rules on seniority (seniority is determined by the time of registration<...>In other words, the pledgee of a future thing may reserve in advance for himself the seniority of his right.<...>The seniority of the pledgee in such a situation is determined by the moment the right of pledge arises (clause 1

On May 18, 1389, Grand Duke Dmitry Ivanovich Donskoy reposed. Before his death, according to the chronicles, he called to himself “the son of his oldest prince Vasily, and gave him his great reign in his own right, his fatherland ... the Russian land; and I gave away to my sons the cities of my fatherland in parts, on which they have princes and divided their lands by lot ... ". Each received the land of the Moscow principality proper and part of the territory of Vladimir, which for the first time became the “fatherland” of the Moscow princes. The title of the Grand Duke of Vladimir and Moscow was transferred to the eldest son

spiritual testament said what he wanted and had to say - the principle of transferring the great reign by seniority<...>Thus, Dmitry Ivanovich departed from the principle of tribal seniority among the princes of the "Kalita's nest",<...>Thirdly, the princess-mother is the guarantor of succession to the throne by seniority.<...>It seems that Dmitry from the very beginning excluded the possibility of a long-term effect of the principle of inheritance by seniority<...>After all, Dmitry Donskoy stipulated in his will only the transition according to the seniority of the Moscow table and not

Topical issues of inheritance law [sat. articles]

M.: Statute

This collection contains articles on such important issues of inheritance law as the emergence and termination of an inheritance relationship, management of the estate, the possibility of disposing of property in the event of death, inheritance of intellectual property rights, etc. The authors of the articles are well-known experts in the field of private law. The book offers a comparative analysis of modern Russian inheritance law and foreign, Soviet and pre-revolutionary inheritance legislation.

Mikheeva Lidia Yuryevna–Deputy HeadofResearchCenterPrivateLawnamedS.S.AlekseevunderPresident<...>Under thesecircumstancesthepublicauthorityappearstofindanother“deputy”owner<...>, moreover, a “deputy”impartialandnotdependingonheirs.Thesefunctionstraditionallyare<...>The logicof the foregoingaccordingtotheheirwhoenteredhisright“replaces”theprevious“deputy<...>.1174Civil Codeof the Russian Federation,refertotocurrentpaymentsof the firstturnandwithintheturnmustsatisfybyseniority

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The nomenclature of organic compounds is a manual for extracurricular work of 2nd year students of full-time and part-time departments of the Faculty of Pharmacy.

The textbook contains generalized results of the rules of the domestic nomenclature of organic compounds, which are the result of adaptation to the Russian language of international rules developed by the nomenclature commissions of IUPAC (International Union of Pure and Applied Chemistry). The rules for constructing the names of all classes of organic compounds that are included as a basis in the composition of medicines are analyzed. The manual is intended for extracurricular work of 2nd year students of full-time and part-time departments of the Faculty of Pharmacy. Compiled in accordance with the State educational standard for the training of pharmacists in the specialty 060108 "Pharmacy" and corresponds to the organic chemistry program approved by the All-Russian Educational and Methodological Center for Continuing Medical and Pharmaceutical Education.

IUPAC rules, only one group is mentioned in the name suffix (the rest in the prefix), then precedence of precedence<...>The remaining substituents are listed in alphabetical order.<...>contains more than one heteroatom, then in the name of such a compound they are listed in descending order of precedence<...>Book-Service "The most common prefixes found in biologically active molecules (by seniority<...>A complex substituent at position 5 of the parent structure.

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A brief biography of Major General Pyotr Semenovich Makhrov, Chief of Staff of the Armed Forces in the South of Russia (1916) is given.

Makhrov, re-forming the headquarters, attracted - regardless of seniority - several young talented<...>First Deputy Gen.

In 1882, the famous pharmacist, Master of Pharmacy Andrey Fedorovich Forbricher and his family became nobles of the Russian Empire. Vorbricher petitioned: “To the Moscow Nobility Assembly of State Councilor Andrei Fedorovich Vorbicher and the sons of Collegiate Assessor Nikolai and Provincial Secretary Sergei Andreevich Vorbricher. Petition. According to the Most Graciously granted me the Order of St. Vladimir of the 4th degree, I wish to be recorded together with my sons, Nikolai and Sergey, in the genealogical book of the Moscow province, why, presenting a copy from the formulary list about my service, a letter of the aforesaid order, certified copies from the birth certificates of the children mentioned and their service records, we have the honor to ask the Assembly of Representatives to include me and my family in the genealogical book and give us a copy of the protocol and the diploma of the nobility, and return the original documents. 1882 October day. State Councilor Andrey Fedorovich Forbricher. Collegiate assessor Nikolai Andreevich Forbricher.

His Imperial Majesty's own Chancellery dated April 3, 1860 No. 2 approved in the X class with seniority<...>Actual problems of modern science, No. 2, 2016 56 was promoted to senior titular councilors for long service<...>of the Governing Senate of August 3, 1864, he was promoted for seniority to collegiate assessors with seniority<...>of the Governing Senate dated September 24, 1868, No. 158, promoted for long service to court advisers with seniority<...>of the Governing Senate of February 8, 1877, No. 27, was promoted to state councilors with seniority for length of service

and V. Prelog in 1966.

The Kahn-Ingold-Prelog rules differ from other chemical nomenclatures, because they are focused on solving a specific problem - the description of the absolute configuration of stereoisomers.

Encyclopedic YouTube

1 / 3

Nomenclature of enantiomers according to the Kahn-Ingold-Prelog system

Name according to R/S-nomenclature (Kahn-Ingold-Prelog system), example 2

Cyclohexane conformations

Subtitles

Now, based on what we already know, if we want to name this molecule, we first need to find the longest carbon chain. We have a two-carbon chain, and all the bonds are single, so we're dealing with ethane. Let's write it all down together. With one of the carbons we have, (let's call it the 1st carbon, which will be the 2nd carbon), we have bromine and fluorine. So we can call it 1-bromine, and we write bromine before fluorine because "b" comes before "f" in alphabetical order. 1-bromo-1-fluorine, and now we're dealing with ethane. We have a two-carbon chain with single bonds - fluoroethane. This is the name of the molecule. I just wanted to repeat the material of the previous videos in which we analyzed the organic nomenclature. Now we already know, based on several previous videos, that this is also a chiral carbon, and if we make it a mirror image, we will have an enantiomer for this molecule, and they will be enantiomers for each other. So what does the mirror image look like for 1-bromo-1-fluoroethane? Here we will have carbon. Let's paint with the same colors. We'll still have bromine upstairs. The methyl group that attaches to the carbon will now be on the left side, CH3. Fluorine, as before, will be behind carbon, and hydrogen will still stick out of the picture, but now to the right. This is hydrogen. As we remember, we called it 1-bromo-1-fluoroethane, and we will also call this molecule 1-bromo-1-fluoroethane, but these are two completely different molecules. Even though they are made up of the same molecules; they have the same molecular formula; the same device, that is, this carbon is connected to hydrogen, fluorine and bromine; and this carbon is connected with the same elements; this carbon is connected to carbon and three hydrogens; just like this one; both are stereoisomers. These are stereoisomers, and they are mirror images of each other, so they are also enantiomers. In fact, they, firstly, polarize light differently, and they have completely different chemical properties, both in the chemical and in the biological system. Therefore, it is not very good that we give the same names for them. in this form, we will focus on how to distinguish between them. So how do we label the differences between them? The naming system we'll be using here is called the Kahn-Ingold-Prelog rule, but it's a different Kahn, it's not me. It is spelled Kan, not Khan. The Cahn-Ingold-Prelog rule is a way of distinguishing between this enantiomer, which we now call 1-bromo-1-fluoroethane, and this enantiomer, 1-bromo-1-fluoroethane. It's pretty simple. The most difficult part is to imagine the rotation of the molecule in the desired direction and to figure out whether this molecule is left-handed or right-handed. Now we will understand this step by step. The first thing we do, according to the Cahn-Ingold-Prelog rule, is identify the chiral molecule. It's pretty obvious here. Here we have carbon. Focus on the left picture we started with. He is connected to 3 different groups. Now we need to sort the groups by atomic number. If we look here, out of bromine, hydrogen, fluorine, and carbon, which is directly bonded to that carbon, what is the largest atomic number? Here's bromine - let's mark it with a darker color. Bromine has a number of 35, fluorine has 9, carbon has 6, and finally hydrogen has 1. That is, among them, bromine has the largest number. Let's assign it number 1. After it comes fluorine. This is #2. #3 is carbon. And hydrogen has the smallest number, so it will be number 4. Now we have numbered them, and the next step is to arrange the molecule so that the group with the smallest atomic number is behind the image. Position it behind the molecule. Hydrogen has the smallest number right now. Bromine has the largest, hydrogen has the smallest, so we need to place it behind the molecule. In the picture, he is now in front of her. And we need to place it behind the molecule, and this is the hardest part - to imagine it correctly. We remember that fluorine is at the back; this is the right side of the image; this part protrudes in front of the image. We need to make a rotation. You can imagine that we rotate the molecule in this direction and ... (let's draw again). Here we will have carbon. And since that's the direction of rotation, we've rotated it about 1/3 around ourselves, which is about 120 degrees. Now hydrogen is in place of fluorine. This is where the hydrogen is. Fluorine is now in place of this methyl group. Here is fluorine. The dotted line shows what is behind. And this is the front. And the methyl group is now instead of hydrogen. She now stands in front of the image. She will be on the left and outside. Here is the methyl group protruding in front of the image, outside and to the left. This is where our methyl group will be. All we did was just rotate the image 120 degrees. We made it go backwards, which is the first step after we've identified the chiral carbon and sorted the elements by their atomic number. Of course, bromine will still be at the top. Now that we have placed the molecule with the smallest atomic number back, let's try to look at the distribution of the other 3. We have 4 molecules. We're looking at the largest one, It's bromine, No. 1. No. 2 is fluorine, No. 2, and then No. 3 is the methyl group. We have a carbon bonded to this carbon, here we have #3. And according to the Cahn-Ingold-Prelog rule, we literally have to go from #1 to #2 to #3? In this case, let's go in that direction. Going from #1 to #2 to #3, we follow clockwise. Let's ignore hydrogen for now. He just stays behind. The first step was to orient it backwards as the smallest molecule. And we are left with 3 big ones, and we have determined the direction in which we need to move from # 1 to 2 and # 3, right? In this case, the direction is clockwise. If we move clockwise, then our molecule is called right-handed, or we can use the Latin word for right, which sounds like rectus. Therefore, now we can call this molecule not just 1-bromo-1-fluoroethane, but add R, R - from the word rectus. You might think that this is from the English right (right), but we will see that S is used for the left side, from the word sinister, so the letter R is still from Latin. And this is our (R)-1-bromo-1-fluoroethane. Here it is. You can guess that this one should be the other way around, it should rotate counterclockwise. Let's do this quickly. The idea is the same. We know the largest element. This is bromine number 1. It is the largest in terms of atomic number. Fluorine is #2. Carbon is #3. Hydrogen is #4. What we need to do is put the hydrogen back, so we'll have to turn it back to where the fluorine is now. If we have to redraw this molecule, then here we have carbon. At the top, there will still be bromine. But we're going to move the hydrogen back, so the hydrogen is now where the fluorine was. Here is our hydrogen. The methyl group, the carbon with 3 hydrogens, will now move to where the hydrogen used to be. It will now protrude in front of the image since we've rotated it in that direction, and here is our methyl group here. And the fluorine now moves to where the methyl group was, and here we have fluorine. Now, using the Kahn-Ingold-Prelog rule, we determine that this is No. 1, This is No. 2, just by atomic number, this is No. 3. We go from No. 1 through No. 2 to No. 3. Right in this direction. Counterclock-wise. In other words, we go to the left, or we can use the Latin word that sounds like sinister. The Latin word sinister in the original means "left". In modern English, the word "sinister" means "sinister". But it has nothing to do with Latin. We will use it simply as a symbol for left. So, we have the left version of the molecule. We'll call this variant, This enantiomer 1-bromo-1-fluoroethane. Let's denote it S, S from the word sinister, that is, left, or counterclockwise: (S) -1-bromo-1-fluoroethane. Now we can distinguish these names. We know that these are two different configurations. And that's what the S and R stand for, and if we're going to make that out of it, we're going to have to literally disconnect and reconnect the different groups. That is, you have to actually break the ties. And in fact, you have to swap these groups in a certain way in order to get this enantiomer from this one. Because they have different configurations, and basically they are different molecules, stereoisomers, enantiomers. Any of these names suits them… Subtitles by the Amara.org community

Determination of precedence

In the modern IUPAC stereochemical nomenclature, configurations of double bonds, stereocenters, and other chirality elements are assigned based on the mutual arrangement of substituents (ligands) at these elements. The rules of Kahn - Ingold - Prelog establish the seniority of deputies, according to the following mutually subordinate provisions.

An atom with a higher atomic number is older than an atom with a lower atomic number. Comparison of substituents is carried out on the atom that is directly connected to the stereocenter or double bond. The higher the atomic number of this atom, the older the substituent. If the first atom of the substituents is the same, the comparison is carried out by atoms that are two bonds away from the stereocenter (double bond) (the so-called atoms of the second layer). To do this, these atoms for each substituent are written out as a list in order of decreasing atomic number and these lists are compared line by line. The deputy in favor of whom the first distinction will be considered the senior is considered. If the seniority of the substituents cannot be determined by the atoms of the second layer, the comparison is carried out by the atoms of the third layer, and so on until the first difference.
An atom with a higher atomic mass is older than an atom with a lower atomic mass. This rule usually applies to isotopes, since they cannot be distinguished by their atomic number.
Sectionis- deputies older sectrans- deputies. This rule applies to substituents containing double bonds or planar four-coordinate fragments.
diastereomeric substituents with like(English like) designations older than diastereomeric substituents with dissimilar(eng. unlike) designations. The former include substituents with the designations RR, SS, MM, PP, sectionissectionis, sectranssectrans, Rsection, Ssectrans, Mseccis And RM, SP. The second group includes substituents with designations RS, MP, RP, SM, sectionsecsectrans, Rsectrans, Ssection, Pseccis And MSektrans.
Deputy with designation R or M older than the deputy with the designation S or P .

The rules are applied sequentially one after the other, if it is not possible to determine the precedence of the deputies using the previous one. The exact wording of Rules 4 and 5 is currently under discussion.

Examples of using

IN R/S-nomenclature

Assigning a Configuration to a Stereo Center R or S is carried out on the basis of the mutual arrangement of substituents (ligands) around the stereocenter. In this case, at the beginning, their seniority is determined according to the Cahn-Ingold-Prelog rules, then the three-dimensional image of the molecule is positioned so that the junior substituent is located behind the image plane, after which the direction of decreasing the seniority of the remaining substituents is determined. If the precedence decreases clockwise, then the stereocenter configuration is denoted R(lat. rectus - right). Otherwise, the configuration is denoted S(lat. sinister - left)

IN E/Z-nomenclature

In the nomenclature of top sides

Main article: Topness

The Kahn-Ingold-Prelog rules are also used to denote the sides of planar trigonal molecules, such as ketones. For example, the sides of acetone are identical because attacking the nucleophile from both sides of the planar molecule results in a single product. If the nucleophile attacks butanone-2, then the sides of butanone-2 are non-identical (enantiotopic), since enantiomeric products are formed when attacking different sides. If the ketone is chiral, then attachment to opposite sides will result in the formation of diastereomeric products, so such sides are called diastereotopic.

To designate the top sides use the notation re And si, which respectively reflect the direction of decreasing order of substituents at the trigonal carbon atom of the carbonyl group. For example, in the illustration, the acetophenone molecule is seen from re-sides.

Notes

. Retrieved February 5, 2013. Archived from the original February 14, 2013.
Cahn R. S., Ingold C., Prelog V. Specification of Molecular Chirality // Angew. Chem. Int. Ed. - 1966. - Vol. 5, no. 4 . - P. 385–415. - DOI:10.1002/anie.196603851 .
Preferred IUPAC Names. Chapter 9 . Retrieved February 5, 2013.

2. Kahn-Ingold-Prelog notation (R-S-nomenclature)

CHAPTER 7. STEREOCHEMICAL BASIS OF THE STRUCTURE OF ORGANIC COMPOUNDS

Found results: 79790 (2.23 sec)

Fundamentals of the structure of organic compounds: Guidelines for 2nd year students of the Faculty of Pharmacy

Systematic Nomenclature of Organic Chemistry: A Directory to Comprehension and Application of its Basic Principles

Chemistry of heterocyclic biologically active substances studies. allowance

Organic chemistry: terms and basic reactions studies. allowance

Organic chemistry. Part I, II studies. allowance

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No. 4 [Posev, 1980]

Structure and properties of hydrocarbons Guidelines

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No. 6 [Refrigeration technology, 2017]

Theory of diplomacy

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Customs diplomacy textbook. allowance

No. 10 [Moscow Journal. History of the Russian State, 2008]

Fundamentals of bioorganic chemistry [proc. allowance]

No. 6 [Bulletin of the European Court of Human Rights, 2016]

No. 4 [Military History Journal, 2008]

Basic course of organic chemistry

Fundamentals of organic chemistry textbook. allowance

Organic chemistry textbook. allowance

No. 4 [Accounting and banks, 2013]

Organic chemistry. Tasks for tests and methods of their solutions. Part 2 studies. allowance

No. 2 [Military History Journal, 2017]

Judicial practice of the European Court of Human Rights on Article 10 of the European Convention. T. 1 collection

Estates, public service and governing bodies of the Russian Empire studies. allowance

No. 8 [World of Legal Science, 2010]

Improving the system of labor motivation for hotel staff in Moscow (on the example of the East Gate Hotel)

Laboratory workshop in organic chemistry

#6 [Law, 2015]

Topical issues of inheritance law [sat. articles]

The nomenclature of organic compounds is a manual for extracurricular work of 2nd year students of full-time and part-time departments of the Faculty of Pharmacy.

Encyclopedic YouTube

Subtitles

Determination of precedence

Examples of using

IN R/S-nomenclature

IN E/Z-nomenclature

In the nomenclature of top sides

Notes

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Chernobyl in the memoirs of eyewitnesses Chernobyl scary stories