Extension and Revision of the von Baeyer System for Naming Polycyclic Compounds (Including Bicyclic Compounds)
(IUPAC Recommendations 1999)


Continued from VB-8.3 to VB-8.5

Contents of Section

VB-9 Configuration of Chiral Systems

VB-9 Configuration of Chiral Systems

The configuration of a chiral ring system with a unique numbering determined by the structure is specified by the R/S system. It may thus be necessary to specify whether the name refers to one enantiomer, a racemate, or is only indicating relative configuration.


CAS index name = [1S-(1[alpha],2[alpha],4[alpha],5[alpha])]-3,6,8-trioxatricyclo[,4]octane

Note A different method of indicating stereochemistry has been adopted by CAS starting with volume 129 of Chemical Abstracts. This would also apply to the names given in VB-8.5.

If it is required to specify that this name applies to a racemate, or that only the relative stereochemistry is known the prefixes rac- or rel- may be used. Thus for the example above:
This example(1S,2R,4R,5S)-3,6,8-trioxatricyclo[,4]octane
Its enantiomer(1R,2S,4S,5R)-3,6,8-trioxatricyclo[,4]octane
Racemic sample(1RS,2SR,4SR,5RS)-3,6,8-trioxatricyclo[,4]octane
Relative configuration only(1R*,2S*,4S*,5R*)-3,6,8-trioxatricyclo[,4]octane


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2. E. Buchner and W. Weigand, Bornylen und Diazoessigester [Nebst einer Nomenklatur tricyclischer Kohlenstoff-Ringsysteme nach Adolf von Baeyer], Ber. Dtsch. Chem. Ges., 46, 2108-2117 (1913).

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4. A.M. Patterson and L.T. Capell, The Ring Index, Reinhold, New York, 1940; A.M. Patterson, L.T. Capell and D.F. Walker, The Ring Index, 2nd edition, American Chemical Society, Washington, DC, 1960 (Supplements 1963, 1964 and 1965). This was continued as the Parent Compound Handbook and then the Ring Systems Handbook 1993 ed., Chemical Abstracts Service, Columbus, Ohio, 1993 (and November 1997 cumulative supplement).

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13. IUPAC Commission on the Nomenclature of Organic Chemistry, Revision of the extended Hantzsch-Widman system of nomenclature for heteromonocycles (Recommendations 1982), Pure Appl. Chem., 55, 409-416 (1983).

14. IUPAC-IUB Joint Commission on Biochemical Nomenclature, Nomenclature of Steroids (Recommendations 1989), Eur. J. Biochem., 186, 429-458 (1989); Pure Appl. Chem., 61, 1783-1822 (1989) and in Dictionary of Steroids (eds R.A. Hill, D.N. Kirk, H.L.J. Makin and G.M. Murphy) Chapman and Hall, London, 1991, pp xxx-lix; IUBMB, Biochemical Nomenclature and Related Documents, second edition, Portland Press, London, 1992, pp 192-221.

15. L.A. Paquette, M.A. Kesselmayer, G.E. Underiner, S.D. House, R.D. Rogers, K. Meerholz and J. Heinze, Multifaceted consequences of holding two [8]annulene rings face-to-face. Synthesis, structural characteristics, and reduction behaviour of [22](1,5)cyclooctatetraenophane, J. Am. Chem. Soc., 114, 2644-2652 (1992).

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