A non-stereospecific synthesis of (±)-davanone

Abstract

A synthesis of the optically inactive form of the natural sesquiterpene davanone (1)together with three stereoisomers has been carried out as in Scheme. Although not subject to steric control, the synthesis confirms the structure of davanone, and leads to the suggestion that the relative stereochemistry may be that shown in (16). The preparation and some reactions with carboxylic acids of 3-methylbut-2-enyllithium are described.