A pH study on the chiral ketone catalyzed asymmetric epoxidation of hydroxyalkenes

被引：120

作者：

Wang, ZX ^{[1
]}

Shi, Y ^{[1
]}

机构：

[1] Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA

来源：

JOURNAL OF ORGANIC CHEMISTRY | 1998年 / 63卷 / 09期

关键词：

D O I：

10.1021/jo972106r

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A detailed study shows that the chiral ketone catalyzed asymmetric epoxidations of hydroxyalkenes are highly pH dependent. The lower enantioselectivity obtained at low pH is attributed to the substantial contribution of the direct epoxidation by Oxone. At high pH the epoxidation mediated by chiral ketone out-competes the racemic epoxidation, leading to higher enantioselectivity. The effective substrates include allylic alcohol, homoallylic alcohol, and bishomoallylic alcohol. In most cases, over 90% ee was obtained.

引用

页码：3099 / 3104

页数：6

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