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Monocyclic Hydrocarbons

Rule A-13. Substituted Aromatic Radicals

13.1 - Univalent radicals derived from monocyclic substituted aromatic hydrocarbons and having the free valence at a ring atom are given the names listed below. Such radicals not listed below are named as substituted phenyl radicals. The carbon atom having the free valence is numbered as 1.

Examples to Rule A-13.1

13.2 - Since the name phenylene (o-, m- or p-) is retained for the radical (exception to Rule A-11.6), bivalent radicals formed from substituted benzene derivatives and having the free valences at ring atoms are named as substituted phenylene radicals. The carbon atoms having the free valences are numbered 1,2-, 1,3- or 1,4- as appropriate.

13.3-The following trivial names for radicals having a single free valence in the side chain are retained:

Examples to Rule A-13.3

13.4 - Multivalent radicals of aromatic hydrocarbons with the free valences in the side chain are named in accordance with Rule A-4.

Examples to Rule A-13.4

13.5 - The generic names of univalent and bivalent aromatic hydrocarbon radicals are "aryl" and "arylene", respectively.

See Recommendations'93 R-9.1, Table 19(b)


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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