Substitutive Nomenclature

General Procedure. Rule C-16.1

16.11 - In the complete name of a compound or radical, the prefixes are arranged in order, as described in the following rules, in front of the parent name. For this purpose the term "parent name" includes any syllables denoting a change of ring members or relating to the structure of a carbon chain; modifying syllables of this kind always stay directly attached to the remainder of the parent name, and are termed "nondetachable".

Examples to Rule C-16.11

(a) Non-detachable parts of parent names:

(i) forming rings: cyclo, bicyclo, tricyclo, etc., spiro.

(ii) breaking rings: seco.

(iii) changing size: nor, homo.

(iv) fusing two or more rings: benzo, naphtho, imidazo, etc.

(v) substituting one ring-member or chain-member for another: oxa, aza, azonia, etc.

(vi) changing positions of ring-members or chain-members: iso, sec-, tert-.

(vii) indicated hydrogen.

(viii) forming bridges: ethano, etc., epoxy, etc.

(ix) hydro (see note).

(b) Detachable prefixes:

(i) denoting substitution: chloro, amino, acetylamino (acetamido), epoxy, methyl, phenyl, imidazolyl, cyclohexyl, imidazotriazolyl, triazaphenanthryl, etc.

(ii) forming hetero bridges: epoxy, etc.

(iii) hydro (see note).

Note: Hydro and syllables denoting subtraction may be treated as detachable or non-detachable.

General Procedure
Rule C-16.2
Rule C-16.3


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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