Studies toward the synthesis of spirastrellolide A. Preparation of a C31–C47 model

Abstract

The synthesis of a C31–C47 model of spirastrellolide A is reported. Key steps include an iron catalyzed cross coupling reaction to incorporate the linear side chain as a single unit, and the carbonyl ene reaction of an exocyclic enol ether to prepare the 5,6-spiroketal. A trans-ketalization from 5,6- to 6,6-spiroketal frameworks is used to facilitate stereochemical assignment.