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.

1. Organic Chemistry Nomenclature
1. Hydrocarbons
o Alkanes
o Alkenes
o Alkynes
o Unsaturated hydrocarbons
o Cyclohydrocarbons
o Aromatic compounds
2. Other functional groups
o Alkyl Halides
o Amines
o Ethers
o Alcohols
o Aldehides & ketones
o Carboxilic acid
o Salts
o Esters
o Amides
o Nitriles
2. Isomery
© Patricio Gómez Lesarri

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

3. 1.1. Alkanes
Single bond: saturated
hydrocarbons
Primary carbon: - CH3
Secondary carbon: -CH2-
Tertiary carbon: -CH-
Nomenclature: Stem + ane
General formula: CnH2n+2

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

8. 1.1. Branched alkanes

9. 1.2. Alkenes
Double bond
Nomenclature: Stem + ene
General formula: CnH2n
Locant just before the suffix –ene
Lowest locant as possible for
double bonds

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

15. 1.5. Arenes
Benzen derivatives
Substituent: phenyl
Disubstituted
Ortho (1, 2)
Meta (1, 3)
Para (1, 4)

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

17. 2. Priority order

18. 2.1.1 Alkyl halides
Functional group: halogen
General formula R-X
Nomenclatur:
Alkyl halide
Substituent: halogen -

19. 2.1.2 Ethers
Functional group: ether
General formula: R-O-R´
Nomenclature:
Suffix ether: Alkylalkylether
Substituent: alkoxy

20. 2.1.3 Amines
Functional group: amino
General formula: R-NH2
Nomenclature:
Substituent amino -
Sufix amina: Alquilamina
Types:
Primary, Secondary, Tertiary

21. 2.1.4 Alcohols
Functional group: hydroxyl
General formula: R-OH
Nomenclature:
 Suffix –ol
 Substituent: hidroxi –
 Phenol

22. 2.2.1 Aldehides
Functional group : carbonyl
Fórmula general: R-CHO
Nomenclature:
Suffix: - al
Substituent: oxo –

23. 2.2.2 Ketones
Functional group: carbonyl
General formula: R-CO-R´
Nomenclature:
Suffix: - one
Suffix: alkylalkylketone
Substituent : oxo -

24. 2.2. Aldehides & ketones

25. 2.3.1 Carboxilic acids
Functional group: carboxyl
General formula: R-COOH
Nomenclature:
Suffix: – oic acid
Substituent: carboxy -

26. 2.3.2 Salts
Functional group: carboxyl
General formula: R-COO-M
Nomenclature:
Suffix: Metal - oate

27. 2.3.3 Esters
Funcional group: ester
General formula: R-COO-R´
Nomenclature:
Suffix: –alkyl - oate

28. 2.3.4 Amides
Functional group: amide
General formula: R-CONH2
Nomenclature:
Suffix: -amide
Substituent: carbamoil-

29. 2.3.5 Nitriles
Functional group: nitrile
Fórmula general: R-CN
Nomenclature:
Suffix: - nitrile
Substituent: cyano –
HCN Cianhidric acid/methanenitrile
CN-
cyanide