Preparation of highly enantiomerically pure linear secondary alcohols via asymmetric reduction of prochiral ketones with borane
作者:Jiaxi Xu、Xianbin Su、Qihan Zhang
DOI:10.1016/s0957-4166(03)00373-2
日期:2003.7
alcohols, via the asymmetric oxazaborolidine-catalyzed borane reduction of prochiral ketones is described. The phenomenon of the enantioselectivity of 1-(4-alkoxylphenyl) alcohols lower than that of 1-(4-alkylphenyl) alcohols was found and rationalized to the coordination of the oxygen atom in the alkoxy groups to the catalyst and borane. Based on the rationale, the enantioselectivity of 1-(4-alkoxylphenyl)
描述了通过不对称的恶唑硼烷催化的手性酮的硼烷还原,有效和实用地制备手性直链仲醇,1-(4-烷基苯基)和1-(4-烷氧基苯基)醇的方法。发现1-(4-烷氧基苯基)醇的对映选择性低于1-(4-烷基苯基)醇的对映选择性的现象,并被合理化为烷氧基中的氧原子与催化剂和硼烷的配位。基于上述原理,随着催化剂量的增加,1-(4-烷氧基苯基)醇在不对称还原中的对映选择性得到提高。