SYNTHESIS AND REACTIONS OF ENANTIOPURE (NEOMETHYLCYCLOPENTADIENYL)IRIDIUM(III) HALIDES WITH SILVER SALTS - A DRAMATIC STERIC EFFECT ON THE COMPETITION BETWEEN INTERMOLECULAR AND INTRAMOLECULAR C-H ACTIVATION

被引：30

作者：

MA, YO

BERGMAN, RG

机构：

[1] LAWRENCE BERKELEY LAB,DIV MAT & CHEM SCI,BERKELEY,CA 94720

[2] UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720

来源：

ORGANOMETALLICS | 1994年 / 13卷 / 07期

关键词：

D O I：

10.1021/om00019a004

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Reactions of enantiomerically pure (NMCp)M-(PMe3)(Me)X complexes (NMCp = neomenthylcyclopentadienyl; M = Rh, Ir) have revealed that the 16-electron (NMCp)M(Pme3)(Me)+ intermediates are achiral (planar) at the metal centers on the time average. Generation of the presumed intermediate (NMCp)Ir-(Pme3) by photolysis of (NMCp)Ir(Pme3)(H)2 in the presence of hydrocarbons results in intermolecular C-H activation. In contrast, the presumed intermediate (NMCp)M(Pme3)(Me)+ exhibits only intramolecular C-H activation involving the neomenthyl group. One of these cyclometalation products has been structurally characterized. The different outcomes of these two systems are attributed to energy differences in the transition states based on molecular mechanics calculations.

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页码：2548 / 2550

页数：3

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