Enantioselective synthesis of the tricyclo[5.2.2.0]undecane skeleton using aprotic Michael-additions; formal total synthesis of (+)-lsoeremolactone

Abstract

The (formal) total synthesis of the diterpene (+)-Isoeremolactone (2) is described starting from the tricyclic ester (15), which was formed by an aprotic Michael-addition (AMA) sequence. The structure of the ester (15) was confirmed by X-ray analysis. The key compound (4) for the synthesis of (2) was made from (15) in 8 steps (25% overall yield).