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Principles of Organic Nomenclature

R-1.1.4 Contiguous formal double bonds

The presence of contiguous formal double bonds at a skeletal atom in a cyclic parent hydride whose name normally implies the maximum number of noncumulative double bonds is described by the symbol , where c is an arabic numeral representing the number of double bonds. The symbol is cited immediately after an expressed locant for the skeletal atom in the name of the parent hydride and follows the symbol, if present.

Examples to R-1.1.4

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

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