New triene synthesis from sorbic acid: two-step synthesis of cis- and trans- galbanolenes
作者:Charles Fehr、José Galindo、Simone Chappuis
DOI:10.1016/s0040-4039(00)92216-0
日期:1992.4
The lithium dianion of sorbic acid reacts with hexanal at the C(2)-position to afford separable anti - and syn-hydroxy carboxylic acids 3 and 4 (87%; =59:41 or 79%; =16:84), whose stereospecific anti-decarboxylative elimination respectively affords (3E, 5Z)- and (3E, 5E)-1,3,5-undecatriene (1) and (2) (cis- and trans-galbanolenes (1 and (2) (69%). An alternative route to 1 involves conversion of 3