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Sulfur Acids and their Derivatives Containing Sulfur Directly Linked to an Organic Radical Rule C-643

643.1 - (a) Compounds containing the grouping or are named sulfonic and sulfinic anhydrides, analogously to carboxylic anhydrides (Subsection C-4.9), and those containing the grouping are named sulfinic sulfonic anhydrides, analogously to mixed carboxylic anhydrides (Rule C-491.3 and C-543.5).

Examples to Rule C-643.1(a)

(b) When the oxygen atom linking the two acid residues of an acid anhydride is replaced by sulfur, the anhydride is named according to the principles of Rule C-491 but with the word "anhydride" replaced by "thioanhydride".

Examples to Rule C-643.1(b)

643.2 - Cyclic anhydrides formed by loss of water between a sulfur acid and a carboxylic acid group, and the analogous imides, are named by replacing "acid" in the name of the corresponding acid by "cyclic anhydride" or "imide", respectively; alternatively, they are named as cyclic compounds by the rules of Section B, with use of "oxide" and a locant to denote oxygen attached to sulfur.

Examples to Rule C-643.2

See Recommendations'93 R-5.7.2, R-3.4, R-5.7.7

Sulfur Acids and Their Derivatives in which Sulfur is Linked Only Through Oxygen to the Organic Radical Rule C-651
Sulfur Acids and Their Derivatives in which Sulfur is Linked Only Through Nitrogen or Through Nitrogen and Oxygen to the Organic Radical Rule C-661, Rule C-662
Sultones and Sultams Rule C-671


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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