Replacement Nomenclature

Rule C-61

61.1 - In an unbranched structure not containing a group that can be named as principal group, the longest chain of carbon and hetero atoms terminating with carbon is chosen and named as though the entire chain were that of an acyclic hydrocarbon. The hetero atoms present within this chain are then named by means of prefixes "aza-", "oxa-", "thia-", etc., as listed in Table B-I of Rule B-1, in the order stated in Rule B-1.4, with locants to indicate their positions in the chain. Methods described in Section A are then used for multiplying prefixes and for denoting unsaturation. The chain is numbered from one end to the other, excluding terminal hetero atoms, according to precedences described in Rule C-62.

Examples to Rule C-61.1

See Recommendations'93 R-1.2.2

Replacement Nomenclature
Rule C-62
Rule C-63
Rule C-64
Rule C-65


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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