Asymmetric synthesis of clerodane diterpenoids: total synthesis of (–)-methyl kolavenate

Abstract

The asymmetric synthesis of (8R,9S,10R)-4,8,9-trimethyl-9-vinyl-Δ⁴-3-octalone, a versatile intermediate for the syntheses of both trans- and cis-neo-clerodane diterpenoids, has been achieved by extension of Ender's asymmetric alkylation, and its utility is exemplified by the total synthesis of (–)-methyl kolavenate, the first example of a clerodane diterpenoid in optically active form.