The activation barrier to axial torsion in 2,2'-bis(diphenylphosphino)biphenyl

被引：58

作者：

Desponds, O ^{[1
]}

Schlosser, M ^{[1
]}

机构：

[1] UNIV LAUSANNE,INST CHIM ORGAN,CH-1015 LAUSANNE,SWITZERLAND

来源：

TETRAHEDRON LETTERS | 1996年 / 37卷 / 01期

关键词：

D O I：

10.1016/0040-4039(95)02080-2

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

After selective deuteriation of 2,2'-bis(diphenylphosphino)biphenyl, it was possible to determine the nmr coalescence temperature of the diastereotopic phenyl groups. On this basis, a torsional barrier of 22 kcal/mol was calculated. Thus, the bisphosphine, even if it could be resolved into pure cnantiomers, would rapidly reracemize at temperatures around or above 25 degrees C.

引用

页码：47 / 48

页数：2

共 8 条

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