Enantioselective reductive cyclization of 1,6-enynes via rhodium-catalyzed asymmetric hydrogenation: C-C bond formation precedes hydrogen activation

被引：97

作者：

Jang, HY ^{[1
]}

Hughes, FW ^{[1
]}

Gong, HG ^{[1
]}

Zhang, JM ^{[1
]}

Brodbelt, JS ^{[1
]}

Krische, MJ ^{[1
]}

机构：

[1] Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2005年 / 127卷 / 17期

关键词：

D O I：

10.1021/ja042645v

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Asymmetric hydrogenation of 1,6-enynes using chirally modified cationic rhodium precatalysts enables enantioselective reductive cyclization to afford alkylidene-substituted carbocycles and heterocycles in a completely atom economical fashion. Good to excellent yields and exceptional levels of asymmetric induction are observed across a structurally diverse set of substrates. Mechanistic studies involving hydrogen-deuterium crossover experiments, along with the observance of nonconjugated cycloisomerization products 14c and 15c, suggest rhodium(III) metallocyclopentene formation occurs in advance of hydrogen activation. This oxidative coupling-hydrogenolytic cleavage motif should play a key role in the design of related hydrogen-mediated couplings. Copyright © 2005 American Chemical Society.

引用

页码：6174 / 6175

页数：2

共 31 条

[1] Cobalt-catalyzed cycloisomerization of 1,6-enynes and allyl propargyl ethers [J].