COMMISSION ON NOMENCLATURE OF ORGANIC CHEMISTRY
Extension and revision of the nomenclature
for spiro compounds
(IUPAC Recommendations 1999)
Prepared for publication by G.P.
Web version prepared by G. P. Moss
Abstract: Spiro ring systems have two or more rings
linked by one common atom. Several different methods are used to name
such systems. Rules A-41, A-43, B-10 and B-12 (Nomenclature of Organic
Chemistry, 1979) describe the basics of how to name these compounds.
The alternative methods in rules A-42 and B-11 are abandoned.
This document describes the nomenclature in greater detail and
extends it to cover branched polyspiro systems and compounds where three
rings have one common spiro atom. A new notation, based on the von Baeyer
method of naming spiro systems where all components are monocyclic,
allows both unbranched and branched polyspiro systems to be named without
ambiguity. It also enables the names to be readily interpreted.
Wide Web version prepared by G. P. Moss