Catalytic, Enantioselective Vinylogous Mukaiyama Aldol Reaction of Furan-Based Dienoxy Silanes: A Chemodivergent Approach to γ-Valerolactone Flavan-3-ol Metabolites and δ-Lactone Analogues
作者:Claudio Curti、Nicoletta Brindani、Lucia Battistini、Andrea Sartori、Giorgio Pelosi、Pedro Mena、Furio Brighenti、Franca Zanardi、Daniele Del Rio
DOI:10.1002/adsc.201500705
日期:2015.12.14
a set of hydroxyphenyl γ-valerolactones was achieved starting from 2-silyloxyfuran and alkoxy-substituted benzaldehydes as common precursors. Key synthesis steps included an enantioselective vinylogous Mukaiyama aldol reaction and a Barton–McCombie deoxygenation. Five enantioenriched γ-valerolactone targets were obtained in 5–6 steps, 18–63% overall yields and 82–98 % ee, paving the way for the straightforward
从2-甲硅烷氧基呋喃和烷氧基取代的苯甲醛作为常见的前体开始,实现了一组羟苯基γ-戊内酯的不对称合成。关键的合成步骤包括对映选择性的乙烯基Mukaiyama aldol反应和Barton-McCombie脱氧反应。通过5–6个步骤获得了5个对映体富集的γ-戊内酯目标,总产率为18–63%,ee为82–98%,这为直接进入此类具有生物有效性且难得的flavan -3-ol代谢物铺平了道路。同时,偶然发现了一种空前的一锅还原环扩展过程,从酚丁醇化物前体产生外消旋的δ-内酯类似物。