Diastereo- and enantioselective synthesis of 4- and 3,4-substituted 2- acetoxy-butyrolactones

Article abstract of DOI:10.1016/S0040-4020(99)00283-5

An efficient asymmetric synthesis of 4-mono-and 3,4-disubstituted 2- acetoxy-butyrolactones 2 has been developed, based on a hydrazone-mediated asymmetric aldol reaction, an intramolecular lactonization and a stereoselective hydrogenation of the resulting butenolides 1. An application of this process in the synthesis of the natural hunger substance 3 (ee = 90%) is also presented.