This document outlines the nomenclature rules for organic chemistry compounds. It discusses the naming of hydrocarbons including alkanes, alkenes, alkynes, and cyclohydrocarbons. It also covers functional groups such as alkyl halides, amines, ethers, alcohols, aldehydes, ketones, carboxylic acids, esters, amides, and nitriles. The document provides IUPAC nomenclature rules including prefixes, suffixes, and locants to systematically name organic structures according to functional groups and compound type.
2. 1. Introduction
Substances which consist of
carbon & hydrogen
(hydrocarbons)
Heteroatoms: O, N, S, P,
Halogens, alkalines, etc.
Carbon tetravalence
C-C bond intensity and length
(350 kJ/mol)
Chains and polymers
4. 1.1. Substituted alkanes
Main chain: longest chain of atoms of carbon
Substituent: branch chain attached to the main chain It is named with
suffix -yl
Nomenclature: branch + main chain
5. 1.1. Branches & substituents
Branchs + main chain
Locants: numbers which precedes a
substituent and show its position.
Hyphen between locant and name.
Comma between two locants
Chain numbered in order to get
lowest locants as possible
Substituents alphabetically
ordered
Prefixes: di-, tri- tetra- for several
branches
6. 1.1. Branched alkanes
When some main chains of the
same length are identified, we
choose one which has greater
number of branches
7. 1.1. Branched alkanes
When there are several main chains of the same length and
number of substituents, the main chain is one which has the
lowest locants
10. 1.2. Branched alkenes
Prefixes di, tri, are used
preceding suffix –ene
Main chain: one which has all
the double bonds
Locant so as to give the place of
branches and double bonds
2-methyl-3-sec-pentylpent-1,3-diene
2-ethyl-3,4-dimethylhex-1,3-diene
11. 1.3. Alkynes
Nomenclature: Stem + yne
General formula: CnH2n-2
Locant just before the suffix –
yne
Lowest locant as possible for
the triple bond
12. 1.3. Branched alkynes
Prefixes di, tri, are used
before suffix –yne
Main chain: one which has
all the triple bonds
Use of locant so as to give
the place of branches and
triple bonds
CH3-C≡C-C≡CH
pent-1,3-diyne
13. 1.3. Unsaturated hydrocarbons
Nomenclature: Stem + en + yne
Use of locants so as to give the position of unsaturations
Lowest locant as possible for all the unsaturations
When there are two choices lower locants are assigned to
doubles bonds
14. 1.4. Cycloalkanes
Hydrocarbons with closed
chains: “rings”
Nomenclature: prefix Cyclo –
General formula: CnH2n
Locant for unsaturations or
substituents
16. 2. Other functional groups
Functional group: group of
atmos or chemical bonds
which give certain chemical
properties to a molecule
Homogous serie: all the
chemical substances which
have the same functional
group onjunto de compuestos
con el mismo grupo funcional
Priority order
Name Functional
group
Suffix
(Main chain)
Prefix
(substituent)
Carboxilic acid R-COOH - oic acid Carboxy -
Salts R-COO-M Metal - oate
Esters R-COO-R Alkyl - oate
Amides R-CONH2 - amide
Nitriles R-CN - nitrile Cyano -
Aldehides R-CHO - al Oxo -
Ketones R-CO-R - one Oxo -
Alcohols R-OH - ol Hidroxi -
Amines R-NH2 -amine Amino -
Ethers R-O-R - ether Alkoxi -
Alkenes C=C - ene
Alkynes C≡C - ine
Halogen R-X - Halogen -
Alkyl R - ane - yl