Intramolecular alkylation of phenols. Part III. Asymmetric induction by a chiral leaving group

Abstract

Intramolecular alkylation of 4-(3-hydroxy-2,4,6-trimethylphenyl)butyl (+)-camphor-10-sulphonate occurred under basic conditions. Both cyclic products were optically active. Optical purities were determined by n.m.r. and absolute configurations by c.d. The nature of the two transition states is compared and used to account for the observed effect. Asymmetric induction was also observed during the intermolecular alkylation of 2,4,6-trimethylphenol with allyl (+)-camphor-10-sulphonate under basic conditions.