Construction of an Enantiomerically Pure 6-Substituted 3,5-syn-Dihydroxyhexanoic Acid System by an Enantioselective Deprotonation Strategy. Formal Synthesis of an Antiobesity Agent, (-)-Tetrahydrolipstatin.

Abstract

Preparation of 6-substituted 4-hydroxytetrahydro-2H-pyran-2-one (12), a key intermediate for the synthesis of (-)-tetrahydrolipstatin, was achieved in an optically pure form by employing an enantioselective deprotonation reaction of the prochiral bicyclic derivative (5) as a key step.