Synthèse des (−)‐(6R)‐et(+)‐(6S)‐tétrahydro‐6‐[(Z)‐pent‐2‐ényl]‐2H‐pyran‐2‐one, lactones de Jasminum grandiflorum L. et de Polianthes tuberosa L.

Abstract

Synthesis of (−)‐(6R)‐ and (+)‐(6S)‐Tetrahydro‐6‐[(Z)‐pent‐2‐enyl]‐2H‐Pyran‐2‐one, lactones from Jasminum grandiflorum L. and from Polianthes tuberosa L.(−)‐(2S)‐Ethyl 2‐hydroxyhexanedioate ((2S)‐2) was obtained by kinetic resolution of racemic ethyl 2‐hydroxy‐hexanedioate with baker's yeast. The key intermediates (+)‐(5R)‐ and (−)‐(5S)‐ethyl 5,6‐epoxyhexanoate ((5R)‐ and (5S)‐6, resp.) are proved to be useful synthons for the total synthesis of chiral 6‐alkyl‐δ‐lactones, as exemplified by the preparation of both enantiomers of jasmine lactone ((6R)‐ and (6S)‐10, resp.).