Synthesis of 4,4a-5,6,7,8-hexahydro-5β-hydroxy-4aβ,8α-dimethylnaphthalen-2(3H)-one, a versatile intermediate for sesquiterpene synthesis

Abstract

Two routes have been examined from 5β-acetoxy-4,4a,5,6,7,8-hexahydro-4aβ-methylnaphthalen-2(3H)-one (10) to 4,4a,5,6,7,8-hexahydro-5β-hydroxy-4aβ,8α-dimethylnaphthalen-2(3H)-one (1), a key intermediate for the synthesis of some types of sesquiterpenoid. The route shown in Scheme 2 is preferable to that in Scheme 1 (although the former is slightly the more lengthy), giving compound (1) in ca. 48% overall yield from (10).