Development of Stereoselective Formation of Carbon-Halogen Bonds

研究了一种由相应的外消旋醇通过对映体的立体保留和对映体的反转合成手性有机卤化物的新方法。用对映体纯苯乙醇和各种胺亲核试剂进行的初步研究表明，对映选择性在很大程度上取决于胺亲核试剂的结构，这表明本方法可能是一种有效的醇类不对称卤化的新方法。我们测试了各种手性有机催化剂，发现一些手性吡啶和膦基有机催化剂对外消旋醇的氯化反应表现出中等的对映选择性。

A new asymmetric synthesis of chiral organo halides from the corresponding racemic alcohols through stereo retention from an enantiomer and inversion for the other one was investigated. Initial study using enantiomerically pure phenethyl alcohol and various amine nucleophiles revealed that the enantioselectivities largely depended on the structure of the amine nucleophiles, suggesting that the present approach can be a potent new methodology for asymmetric halogenation of alcohols.We tested various chiral organocatalysts and found that some chiral pyridine and phosphine based organocatalysts showed moderate enantioselectivities for the chlorination of racemic alcohols.