High enantioselectivities in an (E)-alkene epoxidation by catalytically active chromium salen complexes.: Insight into the catalytic cycle

被引：65

作者：

Daly, AM

Renehan, MF

Gilheany, DG ^{[1
]}

机构：

[1] Univ Coll Dublin, Dept Chem, Dublin 4, Ireland

[2] Univ Coll Dublin, Conway Inst Biomol & Biomed Sci, Dublin 4, Ireland

来源：

ORGANIC LETTERS | 2001年 / 3卷 / 05期

关键词：

D O I：

10.1021/ol0069406

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

[GRAPHICS] The epoxidation of (E)-beta -methylstyrene mediated by an oxochromium salen complex yields the epoxide in 92% ee in stoichiometric mode, the highest ee yet reported for a metal-mediated epoxidation of an (E)-alkene. The effect of added donor ligands, previously substantial, has reached a ceiling with this complex. In catalytic mode a slightly reduced ee and higher yield is obtained, indicating both the presence of a second oxidation cycle and that the major oxidant reacts with its reduced form.

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页码：663 / 666

页数：4

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