Synthesis of enantiopure 1,2-azido and 1,2-amino alcohols via regio- and stereoselective ring-opening of enantiopure epoxides by sodium azide in hot water
作者:Hai-Yang Wang、Kun Huang、Melvin De Jesús、Sandraliz Espinosa、Luis E. Piñero-Santiago、Charles L. Barnes、Margarita Ortiz-Marciales
DOI:10.1016/j.tetasy.2015.12.002
日期:2016.2
A practical and convenient method for the efficient and regio- and stereoselective ring-opening of enantiopure monosubstituted epoxides by sodium azide under hydrolytic conditions is reported. The ring-opening of enantiopure styryl and pyridyl (S)-epoxides by N3 - in hot water takes place preferentially at the internal position with complete inversion of configuration to produce (R)-2-azido ethanols
报道了一种实用且方便的方法,用于在水解条件下通过叠氮化钠对映体纯单取代环氧化物进行有效的区域和立体选择性开环。对映体纯苯乙烯基和吡啶基 (S)-环氧化物在热水中通过 N3 - 开环优先在内部位置发生,构型完全反转,生成对映体含量高达 99% 的 (R)-2-叠氮基乙醇区域选择性,而(S)-金刚烷基环氧乙烷主要以优异的收率提供(S)-1-金刚烷基-2-叠氮基乙醇。一般来说,通过在水/THF中用PPh3还原手性1,2-叠氮基乙醇,可以高收率和优异对映体纯度获得1,2-氨基乙醇,然后转化为Boc或乙酰胺衍生物。