Kinetics study of β-methyl elimination from a metallocene compound of the type Cp2HfR(μ-Me)B(C(6F5)3 (R = alkyl)

被引：26

作者：

Lin, M ^{[1
]}

Spivak, GJ ^{[1
]}

Baird, MC ^{[1
]}

机构：

[1] Queens Univ, Dept Chem, Kingston, ON K7L 3N6, Canada

来源：

ORGANOMETALLICS | 2002年 / 21卷 / 12期

关键词：

D O I：

10.1021/om020108i

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Variable-temperature kinetics studies of the reversible beta-methyl elimination reaction of Cp2Hf(CH2-CMe3)(mu-Me)B(C6F5)(3) (I) to give Cp2Hf(Me)(mu-Me)B(C6F5)(3) and CH2=CMe2 are reported. Activation enthalpies of 21.3(0.5) and 17.0(0.3) kcal/mol in toluene and chlorobenzene, respectively, are shown to represent the energy barrier for beta-methyl migration accompanied by concomitant, solvent-assisted dissociation of[BMe(C6F5)(3)](-) anion from the metal.

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收藏

页码：2350 / 2352

页数：3

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