The synthesis of polyfunctionalized, cyclohexene-based chirons from tartaric acid

Compound ent-1 as well as certain related homochiral and polyfunctionalized cyclohexenes have been prepared from the 1,2-diacetal 4 that is itself readily derived from L-tartaric acid (3). Grignard addition and ring-closing metathesis processes constitute the key steps associated with the reaction sequences involved. This work provides a method for obtaining a range of potentially useful cyclohexenone-containing chirons that are enantiomerically related to those that have been prepared from the homochiral cis-1,2-dihydrocatechol 2, the product of the microbial biotransformation of bromobenzene.