Ftorotan structural formula name by substitution nomenclature. Naming an organic compound

MOSCOW STATE

UNIVERSITY OF ENVIRONMENTAL ENGINEERING

Moscow – 2006

Ministry of Education of the Russian Federation

MOSCOW STATE UNIVERSITY

ENGINEERING ECOLOGY

Department of General and Physical Chemistry

NOMENCLATURE OF ORGANIC COMPOUNDS

Guidelines

Edited by Doctor of Chemical Sciences, Prof. V.S. Pervova

Moscow - 2006

Approved by the editorial and publishing council

Compiled by: G.N. Bespalov, G.S. Isaeva, I.V. Yaroshenko, E.D. Streltsova

UDC. 5.4.7.1

Nomenclature of organic compounds. Methodological instructions./Compiled by: G.N. Bespalov, G.S. Isaeva, I.V. Yaroshenko, E.D. Streltsova

M.: MGUIE, 2006, 28 pp., 2 tables.

The guidelines are intended for students studying in specialties 1705, 1705.06: 1705.07, 1712.03, studying organic chemistry. The paper discusses the basics of the system of naming substances according to rational nomenclature and IUPAC nomenclature. To check the mastery of the material, fifteen variants of tasks are offered.

Reviewers: Department of Chemical Technology of Plastic Masses, Moscow Chemical Technology Institute. D.I. Mendeleev.

Doctor of Chemical Sciences, Prof., A.L. Rusanov, INEOS RAS.

INTRODUCTION

Nomenclature is a system of naming substances. The main requirement for scientific nomenclature is that it unambiguously defines this or that chemical compound, excluding the possibility of mixing this compound with another, would be simple and would allow one to construct its structural formula based on the name of the compound.

There are several different systems. One of the first is trivial nomenclature. Until now, many organic compounds have random historical names. Some of them are associated with being in nature, others with the method of obtaining, others reflect the physical state, and so on. Benzene, alcohol, methane, fulminate acid, formic acid, acetone, ether are trivial names organic matter. These names are not united according to a certain characteristic into a harmonious system and do not reflect the structure of the molecules of organic substances. However, many natural and synthetic substances with complex structures still have trivial names due to their brevity and expressiveness.

The emergence of the theoretical foundations of organic chemistry led to the creation of new classification systems and, consequently, new ways of naming organic compounds that reflect their chemical structure. This means that using the name you can unambiguously compose the structural formula of a substance and, using the structural formula, give the name of the substance. This is how it appeared rational nomenclature and Geneva nomenclature, the further development of which led to the creation of the system IUPAC, proposed by the International Union of Pure Applied Chemistry, recommended for the names of all organic substances. However, in practice one has to deal with different naming systems for organic substances.

To compile the names of organic substances both according to rational nomenclature and according to the IUPAC system, it is necessary to know the names of hydrocarbon radicals. Hydrocarbon radicals- these are particles that are obtained when one or more hydrogen atoms are separated from a hydrocarbon molecule. In hydrocarbon molecules, primary, secondary, tertiary and quaternary carbon atoms should be distinguished, which is determined by the number of its bonds with neighboring carbon atoms. Primary has one bond to a carbon atom, secondary– two bonds with a carbon atom or atoms, tertiary- three, quaternary- four.

When a hydrogen atom is removed from a primary carbon atom, the result is primary radical(that is, the primary carbon atom has a free unit of valence), from the secondary - secondary radical, from tertiary – tertiary radical.

Table 1 shows the formulas of saturated hydrocarbons and the radicals formed from them, as well as their names. As can be seen from the table, only one radical can be formed from methane and ethane. From propane, a hydrocarbon with three carbon atoms, two isomeric radicals can be formed - propyl and isopropyl, depending on which carbon atom (primary or secondary) the hydrogen atom is removed. Starting with butane, hydrocarbons have isomers. In accordance with this, the number of isomeric radicals also increases: n.butyl, sec. butyl, isobutyl, tert. butyl.

The name of subsequent hydrocarbons is composed of the Greek numeral corresponding to the number of carbon atoms in the molecule and the suffix “an”.

As the number of carbon atoms in a hydrocarbon increases, the number of isomers increases, and the number of radicals that can be formed from them also increases.

Most isomers do not have special names. However, according to rational nomenclature and IUPAC nomenclature, any compound, however complex, can be named using the names of simple radicals.

Table 1.

Saturated hydrocarbons and their radicals.

Hydrocarbon


CH 3 -CH 2 -CH 3		CH 3 -CH 2 -CH 2 -	isopropyl (second propyl)
CH 3 - _ CH 2 - CH 2 -CH 3		CH 3 -CH 2 -CH 2 -CH 2 - CH 3 -CH 2 -CH	sec.butyl
	isobutane	CH 3 – CH - CH 2 -	isobutyl tert.butyl

Table 2 shows some unsaturated and aromatic hydrocarbons and their corresponding radicals Table 2.Unsaturated and aromatic hydrocarbons and their radicals.

Hydrocarbons		Radicals

CH 2 =CH-CH 3	propylene	CH 2 =CH-CH 2 - CH=CH-CH 3 CH 2 = C-CH 3	propenyl isopropenyl
	acetylene		acetylenyl or ethynyl

			p(para)-tolyls

RATIONAL NOMENCLATURE

Rational nomenclature is based on type theories. This system is based on the names of the simplest members of homological series: methane, if there are no double bonds, ethylene, if there is one double bond, and acetylene, if the compound has one triple bond. All other hydrocarbons are considered as derivatives of these simplest hydrocarbons, obtained by replacing one or more hydrogen atoms with hydrocarbons radicals. In order to name a particular compound, you need to list the substituent radicals and then name the corresponding hydrocarbon. The listing of radicals should begin with the simplest methyl, and then, as they become more complex, ethyl, propyl, etc. Branched radicals are considered more complex than normal radicals with the same number of carbon atoms. This
connection can be called methylethylisopropylmethane. If a compound contains several identical radicals, then you should indicate how many of these radicals are contained in the compound, using multiplying prefixes - Greek numerals: 2 - di, 3 - three, 4 - tetra, so the compound will be called trimethylethylmethane.

For the central methane atom, it is better to choose the carbon atom that has the largest number of substituents. Depending on which carbon atom is chosen as the central methane atom, the same substance can be given several different names according to rational nomenclature.

Compounds with double and triple bonds are called similarly:

In order to distinguish between two isomeric compounds, two methods can be used. In the first compound, the substituent radicals are located at two different carbon atoms connected by a double bond, symmetrically relative to the double bond. In the second compound, both radicals are located at the same carbon atom, i.e. asymmetrical about the double bond.

That’s why they are called that: the first is symmetrical methylethylene, and the second is asymmetrical methylethylethylene. In the second method, one carbon atom connected to a simpler radical is denoted by the Greek letter , the other by . When naming such compounds, indicate which carbon atom contains which radical. So the first connection will be called  -methyl- -ethylene, and the second -  -methyl- -ethylene.

The name of hydrocarbons, the molecule of which has a symmetrical structure, i.e., consists of two identical radicals, is made up of the names of these radicals and the prefix di-

Cyclic hydrocarbons in rational nomenclature are considered as polymethylenes and are named by the number of methylene groups included in the ring, and Greek numerals are used:

If there are substituents in the cycle, they are listed before the name of the main cycle. This

the connection will be called methylhexamethylene.

Rational nomenclature is still used when naming relatively simple compounds, especially when they want to emphasize the functional type of the compound. However, the naming of highly branched hydrocarbons is difficult, since there are no names for complex radicals.

IUPAC NOMENCLATURE

The IUPAC nomenclature, proposed by the International Union of Pure and Applied Chemistry, makes it possible to name any compound, no matter how complex. This nomenclature is a development and streamlining of the Geneva nomenclature, with which it has much in common.

In this nomenclature, the first four saturated hydrocarbons of normal structure have trivial names: methane, ethane, propane and butane. The names of subsequent normal (unbranched) hydrocarbons are formed from the base of Greek numerals with the addition of the ending -an: C 5 H 12 - pentane, C 6 H 14 - hexane, C 7 H 16 - heptane, etc. (see Table 1)

To name branched hydrocarbons, you must select the longest normal chain. If several chains of the same length can be distinguished in a hydrocarbon, then you should choose the most branched chain. The name of this hydrocarbon, corresponding to the chain length itself, is taken as the basis for the name of this hydrocarbon. Therefore, a hydrocarbon with the structure

will be considered a heptane derivative. This is the longest the chain is numbered, and the direction of numbering is chosen so that the numbers indicating the position of the side chains are the smallest. For each lateral substituent, an Arabic numeral indicates its location in the chain and gives a name. If there are several identical substituents in a compound, then along with indicating the location of each substituent using multiplying prefixes (Greek numerals) di-, tri-, tatra-, and so on, their number is indicated. Lateral substituents are listed in order of increasing complexity: methyl CH 3 - less complex than ethyl C 2 H 5 -, i.e. a radical with a smaller number of carbon atoms is less complex than one with a larger number of atoms. With the same number of carbon atoms, the less complex radical is the one whose main chain

longer: second. butyl
less complex than tert. butyl

Thus, the connection given earlier will be called 2,2,5-trimethyl-3-ethylheptane.

If there are multiple bonds in a hydrocarbon, the longest chain that contains a double or triple bond is taken as the main chain. If a hydrocarbon has one double bond, then the ending –an in the name of the saturated hydrocarbon corresponding in this chain, is replaced by the ending – en and the Arabic numeral indicates the number of the carbon atom at which the double chain begins. So connection

will be called heptin-3.

If a compound contains two double or triple bonds, then the endings of the hydrocarbon names must be – diene or - diin respectively, indicating the numbers of atoms at which multiple bonds begin:

If there are double and triple bonds, the ending in the name of the hydrocarbon will be –en-in indicating the numbers of atoms at which the corresponding multiple bonds begin:

In the case of branched unsaturated hydrocarbons, the main chain is selected in such a way that the positions of the double and triple bonds are designated by the smallest numbers.

The names of cyclic hydrocarbons are formed by adding a prefix to the name of a saturated hydrocarbon with the same number of carbon atoms cyclo-

If there are side substituents, their location, quantity and name are indicated, after which the cyclic hydrocarbon is called.

If the cycle contains multiple connections, this is reflected in the ending changing to -en in the presence of a double bond or ending in –in with one triple bond.

For the simplest monocyclic aromatic compound, the trivial name is retained - benzene. In addition, the trivial names of some substituted aromatic hydrocarbons are retained

Monocyclic aromatic hydrocarbons are considered to be benzene derivatives obtained by replacing hydrogen atoms with hydrocarbon radicals. In order to name a particular aromatic compound, you should number the carbon atoms of the benzene ring, indicate the positions of the substituents in the ring, indicate how many there are, name these radicals, and then name the aromatic hydrocarbon. The positions of the substituents should be designated by the lowest numbers. So the connection

will be called 1,4-dimethyl-2-ethylbenzene.

If the benzene ring has only two substituents, then instead of numbers 1.2-, 1.3- and 1.4- we can use the notation accordingly ortho(o-), meta (m-) and para (n-)

The names of some condensed and polycyclic aromatic hydrocarbons and the order of numbering of carbon atoms are given below.

BIBLIOGRAPHICAL LIST.

Pavlov B.A., Terentyev A.P.. Course in organic chemistry. M.-L.

Homework 1

Option 1.16

a) (CH 3) 2 (CH) 2 (C 2 H 5) 2,

b) (CH 3) 2 CCH(CH 3)

a) methylisopropyl tert.butylmethane,

b) methylethyl acetylene.

a) 2,2,3-trimethylbutane,

b) 3,4-dimethylhexene-3.

Option 2.17

1. Write in expanded form the structural formulas of the following hydrocarbons and name them using rational and IUPAC nomenclature. Indicate how many primary, secondary, tertiary and quaternary carbon atoms are in each compound:

a) (CH 3) 3 CCH(CH 3)CH(CH 3)(C 2 H 5)

b) (CH 3) (C 2 H 5) C 2 (C 2 H 5) 2.

2. Write the structural formulas of the following compounds

and name them according to IUPAC nomenclature:

b) -methyl- -ethyl- -sec.butylethylene.

3.Write the structural formulas of the following compounds and name them using rational nomenclature:

a) 2,2,3,4-tetramethyl-3-ethylpentane,

b) 2,5-dimethylhexine-3.

: Option 3.18

1. Write in expanded form the structural formulas of the following hydrocarbons and name them using rational nomenclature and IUPAC nomenclature. Indicate how many primary, secondary, tertiary and quaternary carbon atoms are in each compound:

a) (CH 3) 3 CCH (C 2 H 5) CH (CH 3) (C 2 H 5),

b) (CH 3) 2 CHС 2 CH(CH 3) 2.

2. Write the structural formulas of the following compounds and name them according to IUPAC nomenclature

a) ethyl div.butylmethane,

b) isopropyl tert.butylacetylene.

3. Write the structural formulas of the following compounds and name them using rational nomenclature:

a) 2,2-dimethyl-3-ethylpentane,

b) 2,2,5,5-tetramethylhexene-3

Option 4.19

a) (CH 3) 2 (CH) 4 (CH 3) (C 2 H 5),

b) (CH 3) 3 C 2 (CH 3) (C 2 H 5) CH (CH 3) 2.

a) methylisopropyl tert.butylmethane,

b) sim.second.butyltert.butylethylene.

3. Write the structural formulas of the following compounds and name them using rational nomenclature:

a)2,2,4,4-tetramethyl-3-ethylpentane,

b) 2,2,5-trimethylhexine-3.

Option 5.20

a) CH 3 (CH 2) 2 CH (C 2 H 5) CH (CH 3) (C 2 H 5),

b) (CH 3) 3 C 4 (CH 3) 3.

2. Write the structural formulas of the following compounds and name them according to IUPAC nomenclature

a) ethylisopropyl isobutylmethane,

b) -ethyl- -isopropyl- -sec.butylethylene.

3. Write the structural formulas of the following compounds and name them using rational nomenclature:

a) 2-methyl-3,3-diethylpentane,

b) butadiene-1,3

Option 6, 21

a) (CH 3) 3 C(CH 2) 2 CH(CH 3) 2,

b) CH 2 C (CH 3) CH CH 2 .

2. Write the structural formulas of the following compounds and name them according to IUPAC nomenclature

a) methylethylisopropyl tert.butylmethane,

b) ,-dimethyl- -sec-butylethylene.

Some names for organic substances, for example, alcohol and ether, came to us from alchemists; many substances received their names in the nineteenth century. Some names directly indicate from which the substance was first isolated: wine alcohol, geraniol, malic, oxalic, formic acid, etc. Others reflect the method of obtaining the substance: sulfuric ether, the name of the scientist who discovered them, etc.

Currently, the nomenclature developed by the IUPAC union is considered generally accepted, although both trivial names (acetic acid, urea) and names based on the principles of outdated nomenclatures (isooctane, tetramethylethylene, etc.) are still widely used.

· The IUPAC nomenclature is based on a substitution principle. It is believed that the structural formula consists of a main chain - carbon atoms connected to each other in an unbranched chain - and substituents attached to them. A substituent is any atom or group of atoms that replaces a hydrogen atom in a straight-chain structure.

· Functional groups that are directly connected to the main chain or are part of it are called in IUPAC nomenclature characteristic groups.

· The name in IUPAC nomenclature consists of a root, which indicates the length of the main chain, as well as prefixes and suffixes, reflecting the presence and location of substituents, multiple bonds and functional groups.

· The name can contain all the blocks, or maybe only two: the root and the suffix of the multiplicity of links.

· The root of the name of the substance comes from the names of unbranched alkanes with a similar chain length.

Rice. 1. Principles of names according to IUPAC nomenclature

To name a substance, you need to know the names of unbranched alkanes. Table 1.

The first four names: methane, ethane, propane and butane arose historically, and the rest come from Greek roots indicating the number of carbon atoms in the molecule.

All names of unbranched alkanes consist of a root and a suffix of the bond multiplicity - en. This suffix means that the substance is extreme - it does not contain double and triple bonds.

A double bond is denoted by the suffix - en, triple - - in.

The unbranched chain can be selected in different ways. In order for the name to be unambiguous, the nomenclature has an algorithm for selecting the main chain.

1. The main chain includes the “senior” characteristic group.

2. Characteristic groups and multiple bonds are included as much as possible in the main chain.

3. The main chain is the longest possible.

4. The main chain is the most branched.

For example, multiple bonds must be included in the main chain (rules 2), even if it is not the longest (rule 3).

Table 2 shows examples of the names of characteristic groups. The arrow on the right shows an increase in seniority: in this table, the higher the group, the “older” it is. The name of the senior characteristic group determines the suffix of the name of the substance. The remaining characteristic groups are designated by prefixes, along with other substituents.

Tab. 2. Names of characteristic groups

1. In the structural formula, select the main chain using the main chain selection algorithm.

2. The main circuit is numbered so that the highest characteristic group receives the lowest number. If such a group is absent, the multiple bond receives the lowest number, and it is assumed that the double bond is older than the triple bond. In the absence of multiple bonds, numbering is carried out so that the substituents receive the lowest numbers.

3. List the substituents with their numbers in alphabetical order, then write down the root of the name corresponding to the number of carbon atoms in the main chain, add the suffix of multiple bonds and the suffix of the senior characteristic group.

4. If a molecule contains several identical substituents or multiple bonds, then use a prefix indicating their number (di-, tri-, tetra-, penta-, hexa-, etc.). Numbers in names are separated by hyphens, and commas are placed between numbers.

During the lesson, you were able to study the topic “Basic principles of the nomenclature of organic compounds.” You learned the names of substances from the IUPAC nomenclature, which is followed all over the world. We looked at the algorithm for choosing the main chain and the procedure for composing the names of organic compounds. We learned how to formulate the names of organic compounds using their structural formula.

video source - http://www.youtube.com/watch?t=1&v=DsF0Bx7FZKc

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CLASSIFICATION AND NOMENCLATURE OF ORGANIC COMPOUNDS

Resonance stabilization.

Steric stabilization factor.

Stabilization of intermediates.

· Free radicals.

· Carbocations, carbanions.

Inductive stabilization (gas phase)

Classification ( lat. classis- rank, facere– do) – distribution of organic compounds into rows, groups, classes depending on their classification characteristics.

The existing classification of organic compounds is based primarily on the structure of the hydrocarbon skeleton and the nature of the functional groups. The classification of organic compounds according to their main characteristics can be presented in the form of a diagram (Fig. 19).

The first classification sign is the structure of the carbon skeleton of the hydrocarbon fragment of the molecule. On this basis, organic compounds are divided into the following series:

· a number of acyclic compounds;

· a number of carbocyclic compounds;

· a number of heterocyclic compounds.

Acyclic compounds[gr. a..., an– particle of negation] – organic compounds in the molecules of which there are no cycles and all carbon atoms are interconnected in straight or branched open chains. Sometimes they are called aliphatic (gr. alefair- fat), since this class includes fats and fatty acids, as well as alicyclic compounds - cycloalkanes, cycloolefins, cyclodienes, cyclodiines.

Figure 19 – Main classes of organic compounds

The structure of the hydrocarbon skeleton can be linear and closed in a cycle. Straight chain of carbon atoms – a chain of atoms connected in series. Branched chain of carbon atoms – a chain of non-sequentially connected atoms: straight chains extend from the middle atoms of a straight chain.

There are two main groups of acyclic compounds:

· rich (limit), in which in the hydrocarbon fragment all carbon atoms are connected to each other only by simple bonds (1);

· unsaturated (unsaturated), in which between the carbon atoms in the hydrocarbon fragment, in addition to simple (single) bonds, there are also double or triple bonds.

Cyclic compounds are divided into carbocyclic, the cycles of which consist only of carbon atoms, and heterocyclic, the composition of which, in addition to carbon atoms, includes atoms of other elements - heteroatoms ( O, N, S and etc. ) .

Carbocyclic compounds– organic compounds characterized by the presence of rings (cycles) of carbon atoms. Carbocyclic compounds are divided into:

· alicyclic compounds;

· aromatic compounds.

Heterocyclic compounds– organic compounds, the cycle of which, in addition to carbon atoms, contains heteroatoms capable of forming at least two covalent bonds (N, O, S).

The second classification feature is electronic structure molecules. On this basis, organic compounds are divided into:

aliphatic compounds

aromatic compounds

The third classification feature is the nature of the functional group that defines the functional class.

Function class– a group of compounds united by a common functional group.

When replaced in a hydrocarbon ( R–H) hydrogen atoms into other atoms or functional groups ( X) new classes of organic compounds are formed ( R–X), the nature of which is determined by functional groups.

Functional group – a heteroatom or a group of non-hydrocarbon atoms that determine belonging to a certain functional class and determine the most important properties this class (Table 6).

Table 6 - Functional derivatives of hydrocarbons

Functional group	Group name	Class name	General formula
	no functional group	alkanes	C n H 2n+2
	double bond (conditional function)	alkenes	C n H 2n
	triple bond (conditional function)	alkynes	C n H 2n-2
	no functional group	arenas	C n H 2n-6
Hal– (F–,Cl–,Br–,I–)	halogen –	halides	R–Hal
OH–	hydroxy –	alcohols	R–OH
OR–	alkoxy –	ethers	R–OR
–O–	epoxy –	epoxy	R–O–R
	carbonyl	aldehydes, ketones
–COOH	carboxyl	carboxylic acids	R–COOH
Continuation of table 6
–COOR	ester	esters	R-COOR
	anhydrite	acid anhydrides
–O–O–	peroxide	peroxides	R–O–O–R
	carbonyl halide	acid halides
	urea	acid amides
–NH 2	amino –	primary amines	R–NH 2
–NH–	imino –	secondary amines	R–NH–R
>N–	aza –	tertiary amines	R3N
–NO 2	nitro –	nitro compounds	R-NO2
–C≡N	carbonitrile (cyano –)	nitriles (cyanides)	R–C≡N
–NH–NH 2	hydrazino –	hydrazines	R–NH–NH 2
–N=N–	azo –	azo compounds	R–N=N–R
–N + ≡N	diazo –	diazo compounds	R–N + ≡N
–SH	thioalcohol (sulfhydride)	thiols (mercaptans)	R–SH
–SR	thioether (alkylthio –)	thioethers (sulfides)	R–SR
	sulfoxide	sulfoxides
–SO3H	sulfo –	sulfonic acids	R-SO3H
E (S, N, O...)	elemento –	organic element compounds	R–E
Me (Na, Li...)	metal –	organometallic compounds	R–Me

Monofunctional compounds– connections with one functional group, for example:

In addition to monofunctional hydrocarbons, there are a wide variety of polyfunctional derivatives with several identical or different functional groups.

Homofunctional compounds– compounds with several identical functional groups, for example:

Heterofunctional compounds– compounds with several different functional groups, for example:

Homologous series[gr. homology– agreement] – a group of related organic compounds with the same functional groups and the same type of structure, differing from each other by one or more methylene groups (–CH 2 –) as part of a hydrocarbon fragment of a molecule and having similar chemical properties.

Homologous difference – (CH 2)n, Where n= 1, 2, 3, etc.

Isological series– a group of hydrocarbons and their derivatives with the same number of carbon atoms in the radical and identical functional groups, but with varying degrees of unsaturation, i.e., with the number of multiple bonds in the radical increasing in each isological series.

Isological difference – (2N)n, Where n = 1, 2

Genetic series – a group of organic compounds with the same hydrocarbon radical in the molecule, but with different functional groups.

The classification of organic compounds allows not only to systematize numerous organic compounds, but is also the foundation for creating rules for constructing the names of any organic compound based on its classical structural formula.

Nomenclature of organic compounds. Nomenclature (lat. nomencklatura– name painting) is a system of rules for constructing the name of a compound. The huge number of organic compounds, the complexity and diversity of their structure determine the complexity of their nomenclature. As organic chemistry developed, several different systems of nomenclature were proposed.

Historically, the first to arise trivial nomenclature (lat. trivialis– ordinary). Organic compounds received random names that reflected either natural sources (malic acid, formic acid, wine alcohol), or noticeable properties (full-throated acid), etc.

With the increase in the number of organic compounds, the need arose to develop clear and unambiguous rules for their naming.

Rational nomenclature connects the name of a substance with its structure and class. The compound is considered as a product of complication of the simplest representative of this class. The rational name is very clear in the case of simple compounds, however, as the structure becomes more complex, the possibilities of rational nomenclature are exhausted.

In order to name a compound using rational nomenclature it is necessary:

· determine the class of the called connection;

· select the base in the compound (Table 7);

Name the surrounding substituents;

· compose a name, starting with the names of simple substituents to more complex ones, ending with the name of the base.

Table 7 - Basics of rational names and endings in the systematic nomenclature of some classes of organic compounds

Called connection class	The basis of a rational name	Ending in systematic nomenclature
alkanes	methane	-an
alkenes	ethylene	-en
alkynes	acetylene	-in
alcohols	carbinol	-an + ol
aldehydes	acetaldehyde	-an + al
ketones	ketone	-an + he
carboxylic acids	acetic acid	-an + oic acid

Both functional groups and hydrocarbon residues can act as substituents. Hydrocarbon radical - the remainder of a hydrocarbon molecule from which one or more hydrogen atoms have been formally removed, leaving one or more valencies free, respectively.

The name of hydrocarbon radicals consists of:

· prefix, indicating the order of connection of carbon atoms in the radical;

· root(base), reflecting the number of carbon atoms;

· suffix: -il – for monovalent radicals;

-ilene – for divalent vicinal radicals;

-iliden – for divalent geminal radicals;

-ilidin – for trivalent geminal radicals.

Hydrocarbon residues can be primary, secondary or tertiary, depending on the type of carbon atom having free valency.

Divalent hydrocarbon residues are formed by removing two hydrogen atoms from a hydrocarbon, while free valences can be located either at one carbon atom or at different ones (Table 8).

In rational nomenclature, several equivalent names are allowed for one compound, depending on the chosen basis.

Table 8 - Hydrocarbons and hydrocarbon residues

Hydrocarbon and its name	Hydrocarbon residues
formula	Trivial names	Character of a radical
C n H 2n+2 alkane	С n H 2n+1 –	alkyl
CH 4 methane	CH 3 –	methyl
СH 3 –СH 3 ethane	СH 3 –СH 2 –	ethyl	primary
CH 3 –CH 2 –CH 3 propane	CH 3 –CH 2 –CH 2 –	cut through	primary
(CH 3) 2 CH–	iso cut through	secondary
CH 3 –(CH 2) 2 –CH 3 butane	CH 3 –CH 2 –CH 2 –CH 2 –	n-butyl	primary
CH 3 – CH (CH 3) – CH 3 isobutane	CH 3 –CH (CH 3) – CH 2 –	iso butyl	primary
CH 3 –CH 2 –(CH 3)CH–	secondary butyl	secondary
(СH 3) 3 С–	tertiary butyl	tertiary
CH 3 –(CH 2) 3 –CH 3	CH 3 –(CH 2) 3 –CH 2 –	n-pentyl (amyl)	primary
isopentane	CH 3 –CH (CH 3) – CH 2 –CH 2 –	iso pentyl	primary
CH 3 –CH 2 –CH(CH 3) –CH 2 –	tues. pentyl	primary
CH 3 –CH 2 –CH 2 –(CH 3)CH–	tues. pentyl	secondary
neopentane	(СH 3) 3 С–СH 2 –	neo pentyl	primary
C n H 2n alkene	C n H 2n - 1 –	alkenyl
Continuation of table 8
CH 2 = CH 2 ethene	СH 2 =СH–	ethenyl	primary
СH 3 –СH=СH 2 propene	СH 2 =СH–СH 2 –	propenyl – 2 (allyl)	primary
СH 3 –СH=СH–	propenyl	primary
C n H 2n -2 alkyne	C n H 2n -3 –	alkynyl
CH≡CH ethin	СH≡С–	ethynyl	primary
СH 3 –С≡СH propyne	СH 3 –С≡С–	propinil	primary
СH≡С–СH 2 –	propinil – 2 (propargyl)	primary
C n H 2n -6 arenas	C n H 2n -7	aryl	–
C 6 H 6	C 6 H 5 –	phenyl	–
C 6 H 5 –CH 3 toluene	C 6 H 5 –CH 2 –	benzyl	primary
СH 3 –С 6 H 4 –	toluidil ( O–, P–, m–)	–
CH 4 methane	–CH 2 –	methylene	–
CH 2 = CH 2 ethene	CH 2 =C<	vinylidene	–

Prefix – prefix (lat. praefixum from prae– ahead + fixus– attached). Prefixes n-, second.-, third.- are in italics and separated from the base by a hyphen.

Prefixes printed in italics are not taken into account when arranging substituents in the name in alphabetical order.

The following are in italics:

· prefixes: n-, sec.-, tert.-, cis-, trans-, D-, L-, R-, S-, E-, Z-, syn-, anti-, endo-, exo-, gosh-;

· letter locants: α-, β-, γ- etc. ortho (o-), meta (m-), para, (n-), N.

The letters of the Latin alphabet precede the letters of the Greek alphabet.

Hyphen (lat. divisio- division) - a short connecting line between two words. It is used to separate the base of digital and alphabetic locants and prefixes in italics from the name.

Multiplying prefixes:

· di-, tri-, tetra-, penta-, etc. are used to indicate the number of identical unsubstituted radicals, for example triethylamine;

· bis-, tris-, tetrakis-, pentakis-, etc. used to denote the number of identical equally substituted radicals, for example bis-(2-chloroethyl)amine, tris-(2-chloroethyl);

· bi-, ter-, quarter- are used to indicate the number of identical rings connected to each other by a bond.

Vicinal radical(lat. vicinus– adjacent): free valences are located at neighboring carbon atoms.

Geminal radical(lat. geminus– twins): free valences are located at the same carbon atom.

Note. Geminal divalent radical:

· –CH 2 – denoted by the suffix -ylene (methylene);

· –CH 2 –CH 2 –CH 2 – called trimethylene;

· –CH 2 (CH 3)CH– denoted by the suffix -ylene (propylene).

Systematic nomenclature. In 1892 it appeared Geneva nomenclature . Later its provisions were revised into Liege nomenclature (1930). In 1957 they adopted IUPAC rules (International Union of Pure and Applied Chemistry).

Within the framework of this nomenclature, compounds are considered as products of complication of normal saturated hydrocarbons or substituted cycles obtained by replacing hydrogen atoms with any structural fragments. The nature of the substituent is indicated by a prefix (prefix) or ending. To clarify the position, the base atoms (locants) are numbered.

Methods for constructing names in nomenclature IUPAC (using the example of an acyclic connection):

· choose the basis, which is the longest chain of carbon atoms, which contains functional groups and multiple bonds;

· number the base starting from the most substituted end. The beginning of the numbering is determined by the highest functional group, then the multiple bond and the hydrocarbon substituent. In order of decreasing precedence, some functional groups are arranged as follows:

· compose a name that includes the name of the substituents in alphabetical order, the name of the main chain, the ending characteristic of the multiple bond and the senior functional group. The position of substituents and functional group is indicated by numbers, their number - by Greek numerals.

1. 2-amino-4-methylthiobutanoic acid:

2. 3-methyl-4-chloroformyl-ethyl-butanoate:

3. 4-amino-2-hydroxybenzenecarboxylic acid.

During the lesson you will be able to study the topic “Basic principles of the nomenclature of organic compounds.” You will learn the names of substances according to the IUPAC nomenclature, which is followed all over the world, consider the algorithm for choosing the main chain, and the procedure for compiling the names of organic compounds. Learn to form the names of organic compounds using their structural formula.

Topic: Introduction to organic chemistry

Lesson: Basic principles of organic compound nomenclature

· Functional groups that are directly connected to the main chain or are part of it are called in IUPAC nomenclature characteristic groups.

· The name can contain all the blocks, or maybe only two: the root and the suffix of the multiplicity of links.

· The root of the name of the substance comes from the names of unbranched alkanes with a similar chain length.

Rice. 1. Principles of names according to IUPAC nomenclature

To name a substance, you need to know the names of unbranched alkanes. Table 1.

The first four names: methane, ethane, propane and butane arose historically, and the rest come from Greek roots indicating the number of carbon atoms in the molecule.

All names of unbranched alkanes consist of a root and a suffix of the bond multiplicity - en. This suffix means that the substance is extreme - it does not contain double and triple bonds.

A double bond is denoted by the suffix - en, triple - - in.

The unbranched chain can be selected in different ways. In order for the name to be unambiguous, the nomenclature has an algorithm for selecting the main chain.

1. The main chain includes the “senior” characteristic group.

2. Characteristic groups and multiple bonds are included as much as possible in the main chain.

3. The main chain is the longest possible.

4. The main chain is the most branched.

For example, multiple bonds must be included in the main chain (rules 2), even if it is not the longest (rule 3).

Tab. 2. Names of characteristic groups

1. In the structural formula, select the main chain using the main chain selection algorithm.

Bibliography

1. Rudzitis G.E. Chemistry. Basics general chemistry. 10th grade: textbook for educational institutions: a basic level of/ G. E. Rudzitis, F. G. Feldman. - 14th edition. - M.: Education, 2012.

2. Chemistry. Grade 10. Profile level: textbook for general education institutions/ V.V. Eremin, N.E. Kuzmenko, V.V. Lunin et al. - M.: Bustard, 2008. - 463 p.

3. Chemistry. Grade 11. Profile level: academic. for general education institutions/ V.V. Eremin, N.E. Kuzmenko, V.V. Lunin et al. - M.: Bustard, 2010. - 462 p.

4. Khomchenko G.P., Khomchenko I.G. Collection of problems in chemistry for those entering universities. - 4th ed. - M.: RIA "New Wave": Publisher Umerenkov, 2012. - 278 p.

Homework

1. Nos. 8, 9 (p. 22) Rudzitis G.E., Feldman F.G. Chemistry: Organic chemistry. 10th grade: textbook for general education institutions: basic level / G. E. Rudzitis, F.G. Feldman. - 14th edition. - M.: Education, 2012.

2. Name the trihydric alcohol glycerin according to the international nomenclature.

3. Write the structural formula of 2,5-dimethyl,3-ethyloctane. Which homologous series does this substance belong to?

Organic chemistry is the chemistry of carbon compounds, or, in other words, the chemistry of hydrocarbons and their derivatives. What is the classification and nomenclature of organic compounds?

What are organic compounds?

Based on their composition, organic compounds are divided into classes - hydrocarbons and functional derivatives of hydrocarbons.

Hydrocarbons are organic compounds that contain only carbon and hydrogen atoms (and are based on a chain built from carbon atoms).

Rice. 1. Table of hydrocarbons.

Functional derivatives of hydrocarbons have one or more functional (active) groups that contain atoms of other elements (except carbon and hydrogen) and determine the properties of this class of compounds. Functional groups include atoms of elements such as oxygen, nitrogen, and sulfur. The main classes of organic compounds are characterized by the type of functional groups.

According to the shape of the carbon chain, organic compounds are divided into compounds of normal and isostructure, as well as compounds with an open carbon chain (acyclic) and with a closed carbon chain (cyclic).

Compounds of normal structure have a carbon chain without branches, while compounds of isostructure have branches in the carbon chain

Rice. 2. Types of carbon chains.

Type chemical bond between carbon atoms, organic compounds are divided into saturated (saturated) and unsaturated (unsaturated). Saturated ones contain only simple carbon-carbon bonds, and unsaturated ones contain at least one multiple bond.

Open chain compounds - saturated and unsaturated - are called fatty compounds, or aliphatic.

Cyclic compounds (saturated and unsaturated) are called alicyclic.

There are compounds with a special type of bond called aromatic

Nomenclature of organic compounds

Currently, organic compounds are named according to the rules of the International Systematic Nomenclature. For compounds common in everyday life and industry, especially natural ones, a trivial nomenclature is used, including historically established names. For some, especially monofunctional, compounds, a type of MSN is used - radical functional nomenclature.

Basic principles for naming a compound according to MSN:

the molecule is considered as a derivative of a saturated hydrocarbon;
in the molecule, the longest carbon chain containing a functional group or multiple bond, if any, is selected. the chain is called the corresponding saturated hydrocarbon;
the main circuit is numbered from the end to which it is closest senior group in a molecule;
if there is a multiple bond in the main chain, then in the name of the saturated hydrocarbon the ending -an changes to the corresponding one;
if there is a functional group in the main chain, then the corresponding ending is added to the name of the main chain;
Before the name of the main chain, the names of radicals that are not part of the main chain, but associated with it, are listed, with the addition of one locant for each radical.