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Monocyclic Hydrocarbons

Rule A-12. Substituted Aromatic Compounds

12.1 - The following names for monocyclic substituted aromatic hydro carbons are retained:

Examples to Rule A-12.1

12.2 - Other monocyclic substituted aromatic hydrocarbons are named as derivatives of benzene or of one of the compounds listed in Part .1 of this rule. However, if the substituent introduced into such a compound is identical with one already present in that compound, then the substituted compound is named as a derivative of benzene (see Rule 61.4).

12.3 - The position of substituents is indicated by numbers except that o- (ortho), m- (meta) and p- (para) may be used in place of 1,2-, 1,3-, and 1,4-, respectively, when only two substituents are present. The lowest numbers possible are given to substituents, choice between alternatives being governed by Rule A-2 so far as applicable except that when names are based on those of compounds listed in Part .1 of this rule the first priority for lowest numbers is given to the substituent(s) already present in those compounds.

Examples to Rule A-12.3

12.4 - The generic name of monocyclic and polycyclic aromatic hydrocarbons is "arene".

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

Substituted Aromatic 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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