Appendix C
Proposals on Consistent Numbering of Bicyclics and Menthane-Type Monocyclics Several reviewers of the June 1950 version of this report suggested, in the in terest of homogeneity, that: (1) the bicyclic fundamental parent structures should be numbered so that a return to the monocyclic forms would not change that number ing; (2) the actual or potential isopropyl group should always be attached to the No. 1 ring carbon in both the bicyclic structures and the menthane-type monocyclic structures. The American committees decided this was not feasible (see report proper). A summary of the specific proposals made by reviewers follows. 1. B y Georges Dupont Professor Dupont, in a letter of March 5, 1952, expressed the opinion that the numbering in going from bicyclics to monocyclics should be preserved as much as possible — for example, for the transformation pinene --> limonene, it would be useful to preserve the numbering. This would be obtained if α-pinene retained its classical formula (I) and if for limonene (II) the numbering corresponded to that re quired for menthene on the basis of the Chemical Abstracts alphabetic order of prec edence of the names of the substituents — i.e., isopropyl methyl — thus:
