Asymmetric syntheses of 3-substituted-cyclohexanone derivatives by stereoselective conjugate addition to chiral 2-substituted-2-cyclohexen-1-ones
作者:Arthur G. Schultz、Roger E. Harrington
DOI:10.1021/ja00013a031
日期:1991.6
Chiral 2-substituted-2-cyclohexen-1-one 2a is prepared. Conjugate additions of organometallic reagents to 2a occur with good to excellent diastereoselectivities. Enone 2b, which contains an additional potentially coordinating oxygen atom on the side chain of the chiral auxiliary, gave about the same stereoselectivity as 2a. The chiral auxiliary (S)-(+)-2-(methoxymethyl)pyrrolidine can be removed from
制备手性2-取代-2-环己烯-1-酮2a。有机金属试剂与 2a 的共轭加成具有良好到极好的非对映选择性。Enone 2b 在手性助剂的侧链上包含一个额外的潜在配位氧原子,其立体选择性与 2a 大致相同。手性助剂 (S)-(+)-2-(甲氧基甲基)吡咯烷可通过在 60°C 下用盐酸羟胺和醋酸钠在 95% 乙醇中处理从缀合物加成产物中去除,得到 3-取代环己酮