On the economic application of DuPHOS rhodium(I) catalysts: a comparison of COD versus NBD precatalysts

被引：31

作者：

Cobley, CJ ^{[1
]}

Lennon, IC ^{[1
]}

McCague, R ^{[1
]}

Ramsden, JA ^{[1
]}

Zanotti-Gerosa, A ^{[1
]}

机构：

[1] Chirotech Technol Ltd, Unit 321, Cambridge CB4 0WG, England

来源：

TETRAHEDRON LETTERS | 2001年 / 42卷 / 42期

关键词：

D O I：

10.1016/S0040-4039(01)01552-0

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The effectiveness of cyclooctadiene and norbornadiene precatalysts of the type [Rh(DuPHOS)(diolefin)]BF4 in catalytic asymmetric hydrogenation of various prochiral olefins has been examined. In some of the systems studied, the NBD complex gave rise to the catalytically active species more rapidly than the corresponding COD complex, as expected. However, as catalyst loadings were reduced to levels more conducive to economic manufacture, the difference between the use of COD and NBD precatalysts became increasingly insignificant. This was conveniently highlighted by the formation of low enantiomeric excess products upon using an equimolar mixture of (S,S) and (R,R) precatalysts, bearing COD and NBD respectively. With other substrates, the system displayed no induction time for either precatalyst and identical reaction profiles were observed. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：7481 / 7483

页数：3

共 5 条

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