Ultrasound assisted reductive cleavage of eudesmane and guaiane γ-enonelactones. Synthesis of 1α,7α,10αH-guaian-4,11-dien-3-one and hydrocolorenone from santonin
作者:Gonzalo Blay、Victoria Bargues、Luz Cardona、Begoña Garcı́a、José R Pedro
DOI:10.1016/s0040-4020(01)00986-3
日期:2001.11
Ultrasound enhances the rate of reductive cleavage of the C-6-oxygen bond of sesquiterpene enonelactones. trans-Eudesmanolides 1c-1g, cis-eudesmanolides 2a-2c, and trans-guaianolides 4a-4d react with Zn in acetic acid-H2O under sonochemical conditions to afford the corresponding sesquiterpene. acids 3a-3g and 5a-5d, respectively in good yields. Starting from 5d two natural guaianes 1 alpha ,7 alpha ,10 alphaH-guaian-4, 11-dien-3-one (6) and hydrocolorenone (7) have been prepared in good yields through a straightforward sequence. (C) 2001 Elsevier Science Ltd. All rights reserved.