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Hydrocarbon Ring Assemblies

Rule A-54. Three or More Identical Ring Systems

54.1 - Unbranched assemblies consisting of three or more identical hydrocarbon ring systems are named by placing an appropriate numerical prefix before the name of the hydrocarbon corresponding to the repetitive unit. The following numerical prefixes are used:

3. ter- 7. septi-
4. quater- 8. octi-
5. quinque- 9. novi-
6. sexi- 10. deci-

Example to Rule A-54.1

54.2 - Unprimed numbers are assigned to one of the terminal systems, the other systems being primed serially. Points of attachment are assigned the lowest numbers possible.

Examples to Rule A-54.2

54.3 - As exceptions, unbranched assemblies consisting of benzene rings are named by using the appropriate prefix with the radical name "phenyl".

Examples to Rule A-54.3

See Recommendations'93 R-2.4.4

Radicals for Identical Ring Systems
Radicals for Non-benzenoid Ring Systems


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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