分子内不对称Heck反应中手性季碳中心生成的电子控制

Electronic control of chiral quaternary center creation in the intramolecular asymmetric heck reaction.

作者信息

Busacca Carl A, Grossbach Danja, Campbell Scot J, Dong Yong, Eriksson Magnus C, Harris Robert E, Jones Paul-James, Kim Ji-Young, Lorenz Jon C, McKellop Keith B, O'Brien Erin M, Qiu Fenghe, Simpson Robert D, Smith Lana, So Regina C, Spinelli Earl M, Vitous Jana, Zavattaro Chiara

机构信息

Departments of Chemical Development and Analytical Sciences, Boehringer-Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Rd., Ridgefield, Connecticut 06877, USA.

出版信息

J Org Chem. 2004 Aug 6;69(16):5187-95. doi: 10.1021/jo049448z.

DOI:10.1021/jo049448z

PMID:15287760

Abstract

The Boehringer-Ingelheim phosphinoimidazoline (BIPI) ligands were applied to the formation of chiral quaternary centers in the asymmetric Heck reaction. Several different substrates were examined in detail, using more than 70 members of this new ligand class. Hammett relationships were determined through systematic variation of the ligand electronics. All substrates showed essentially the same Hammett behavior, where enantioselectivity increased as the ligands were made more electron-deficient. Ligand optimization has led to catalysts which give the highest enantioselectivities reported to date for these difficult systems.

摘要

勃林格殷格翰磷酰亚胺咪唑啉（BIPI）配体被应用于不对称Heck反应中手性季碳中心的形成。使用这一新配体类别的70多个成员，详细研究了几种不同的底物。通过系统改变配体电子性质确定了哈米特关系。所有底物都表现出基本相同的哈米特行为，即随着配体电子缺乏程度增加，对映选择性提高。配体优化已产生了迄今报道的针对这些困难体系具有最高对映选择性的催化剂。