Enantioselective Synthesis of β-Pyrazole-Substituted Alcohols through an Asymmetric Ring-Opening Reaction of meso-Epoxides
作者:Xiaolei Hu、Bo Gao、Yangyang Chu、Wei Li、Xiaohua Liu、Lili Lin、Xiaoming Feng
DOI:10.1002/chem.201103792
日期:2012.3.19
An efficient and practical synthesis of optically pure β‐pyrazole‐substituted alcohols was achieved by an asymmetric ring‐opening reaction of meso‐epoxides with pyrazole derivatives as the nucleophile. In the presence of 1 mol % of an N,N′‐dioxide–Sc(OTf)3 complex, excellent enantioselectivity and yields were obtained from meso‐epoxides. The process could also be used for a mixture of cis‐ and trans‐stilbene
通过内消旋环氧化物与吡唑衍生物作为亲核试剂的不对称开环反应,可以有效,实用地合成光学纯的β-吡唑取代的醇。在1 mol%的N,N'-二氧化物–Sc (OTf)3络合物存在下,内消旋环氧化合物具有出色的对映选择性和收率。该方法也可用于顺式和反式二苯乙烯氧化物的混合物。提供了建议的过渡状态模型。