Concise stereoselective synthesis of cis-3-alkoxy-2-carbomethoxy medium-ring oxacycles from (R)-3-(3-butenyl)-4-propynoyloxazolidin-2-one
作者:Daisuke Sato、Kenshu Fujiwara、Hidetoshi Kawai、Takanori Suzuki
DOI:10.1016/j.tetlet.2007.12.111
日期:2008.2
A concise process for the stereoselective synthesis of chiral cis-3-alkoxy-2-carbomethoxy medium-ring oxacycles from (R)-3-(3-butenyl)-4-propynoyloxazolidin-2-one (1) was developed. The process includes five major steps: (i) hetero-Michael reaction between an alcohol and 1, (ii) stereoselective reduction of the resulting ketone, featuring stereochemical assistance of the neighboring oxazolidin-2-one
开发了一种简明的方法,用于从(R)-3-(3-丁烯基)-4-丙炔基恶唑烷丁二酮(1)立体选择性地合成手性顺式-3-烷氧基-2-羰甲氧基中环氧杂环。该方法包括五个主要步骤:(i)醇与1之间的杂-迈克尔反应,(ii)立体选择性还原生成的酮,其特征在于相邻的恶唑烷二-2-酮基团的立体化学辅助,(iii)用烷氧基酯化乙酸,(iv)生成的手性转移的爱尔兰–克莱森重排,生成3-烷氧基烯丙基乙醇酸酯,以提供顺式-2,3-二烷氧基羧酸酯,和(v)中继闭环烯烃复分解反应以形成中环醚,同时除去恶唑烷-2-酮部分。