Exceptionally simple enantioselective syntheses of chiral hexa- and tetracyclic polyprenoids of sedimentary origin

Abstract

Coupling between a sulfone and an acylsilane fragment constitutes the first step in the exceptionally short total syntheses of two chiral hexacyclic hydrocarbons isolated from Eocene Messel shale (Germany). Like the first step, subsequent steps also employ a powerful synthetic tactic: polycyclization of a specially constructed chiral, multiply unsaturated oxirane. TBS = tBuMe2Si.