Replacement Nomenclature

Rule C-62

62.1 - In an unbranched structure containing one or more groups that can be named as principal groups the latter are selected in the same way as for carbon chains and are similarly named; substitutive nomenclature is used. Locants are applied to the chain, excluding terminal hetero atoms, in accordance with the following criteria, applied successively so far as necessary:

(i) lowest locants to the principal groups;

(ii) lowest locants to the hetero atoms considered together, and if there is a choice, to the hetero atoms cited first in Table B-I of Rule B-1. In the order of precedence any "onia" prefix follows the corresponding "a" prefix

(iii) according to the principles stated in Rules A-3.1, A-3.2, A-3.3, and A-3.4.

Examples to Rule C-62.1

(Note: In polyesters named by this method the locants of carbonyl groups differ by unity from the locants of oxa groups. Similar differences apply in the names of polyamides.)

(cf Rule D-1.5)

See Recommendations'93 R-1.2.2

Replacement Nomenclature
Rule C-63
Rule C-64
Rule C-65


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