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Acyclic Hydrocarbons

Rule A-1. Saturated Unbranched-chain Compounds and Univalent Radicals

1.1 - The first four saturated unbranched acyclic hydrocarbons are called methane, ethane, propane and butane. Names of the higher members of this series consist of a numerical term, followed by "-ane" with elision of terminal "a" from the numerical term. Examples of these names are shown in the table below. The generic name of saturated acyclic hydrocarbons (branched or unbranched) is "alkane".

Examples of names:

(n = total number of carbon atoms)

n n
1 Methane 22 Docosane
2 Ethane 23 Tricosane
3 Propane 24 Tetracosane
4 Butane 25 Pentacosane
5 Pentane 26 Hexacosane
6 Hexane 27 Heptacosane
7 Heptane 28 Octacosane
8 Octane 29 Nonacosane
9 Nonane 30 Triacontane
10 Decane 31 Hentriacontane
11 Undecane 32 Dotriacontane
12 Dodecane 33 Tritriacontane
13 Tridecane 40 Tetracontane
14 Tetradecane 50 Pentacontane
15 Pentadecane 60 Hexacontane
16 Hexadecane 70 Heptacontane
17 Heptadecane 80 Octacontane
18 Octadecane 90 Nonacontane
19 Nonadecane 100 Hectane
20 Icosane 132 Dotriacontahectane
21 Henicosane
1.2 - Univalent radicals derived from saturated unbranched acyclic hydrocarbons by removal of hydrogen from a terminal carbon atom are named by replacing the ending "-ane" of the name of the hydrocarbon by "-yl". The carbon atom with the free valence is numbered as 1. As a class, these radicals are called normal, or unbranched chain, alkyls.

Examples to Rule A-1.2

See Recommendations'93 R-2.2.1

Saturated Branched-chain Compounds and Univalent Radicals
Unsaturated Compounds and Univalent Radicals
Bivalent and Multivalent Radicals


This HTML reproduction of Sections A, B and C of IUPAC "Blue Book" is as close as possible to the published version [see Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F, and H, Pergamon Press, Oxford, 1979. Copyright 1979 IUPAC.] If you need to cite these rules please quote this reference as their source.

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