Synthesis of a Constitutional Isomer of Nerol by Consecutive Ireland–Claisen and Cope Rearrangements
作者:Philip Kraft、Walter Eichenberger、Georg Fráter
DOI:10.1002/(sici)1099-0690(199911)1999:11<2781::aid-ejoc2781>3.0.co;2-c
日期:1999.11
3-methylbut-2-en-1-oic acid (senecioic acid, 8), followed by selective Ireland–Claisen rearrangement of the resulting ester 9 at 0°C and subsequent Cope rearrangement of the product at 140°C. A standard LAH reduction in the last step of the synthetic sequence transformed the α,β-unsaturated acid 12 into the target molecule 6, a constitutional isomer of nerol (5) with interesting olfactory properties.
(2Z,6E)-3,6-Dimethylocta-2,6-dien-1-ol (6) 通过 (2E)-2-methylbut-2-en-1-ol(tiglic 醇,7 ) 与 3-methylbut-2-en-1-oic 酸 (seneciic acid, 8),然后在 0°C 下对所得酯 9 进行选择性爱尔兰-克莱森重排,然后在 140°C 下对产物进行 Cope 重排。在合成序列的最后一步中,标准的 LAH 还原将 α,β-不饱和酸 12 转化为目标分子 6,这是一种具有有趣嗅觉特性的橙花醇 (5) 的结构异构体。