Models for intermediates in metallocene-catalyzed alkene polymerization:: Alkene dissociation from Cp2Zr[η1 η2-CH2Si(CH3)2CH2CH=CH2][B(C6F5)4]

被引：40

作者：

Casey, CP ^{[1
]}

Carpenetti, DW ^{[1
]}

Sakurai, H ^{[1
]}

机构：

[1] Univ Wisconsin, Dept Chem, Madison, WI 53706 USA

来源：

ORGANOMETALLICS | 2001年 / 20卷 / 20期

关键词：

D O I：

10.1021/om0103658

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The bis(allyldimethylsilylmethyl)bis(cyclopentadienyl)zirconium complex Cp2Zr[CH2Si-(CH3)(2)CH2CH=CH2](2) (5) reacted rapidly with [(C6H5)(2)(CH3)NH] [B(C6F5)(4)] in CD2Cl2 at - 78 degreesC to form the cationic zirconium- alkyl-alkene complex Cp2Zr[eta (1), eta (2)-CH2Si(CH3)(2)CH2CH= CH2] [B(C6F5)(4)] (6). Low-temperature H-1 and C-13 NMR spectroscopy established the coordination of the tethered alkene to the d(0) metal center. Line shape analysis of the coalescence of the diastereotopic Cp ligand resonances allowed measurement of the alkene dissociation energy barrier [DeltaG(double dagger)(-28 degreesC) = 12.7 +/- 0.8 kcal mol(-1)].

引用

页码：4262 / 4265

页数：4

共 41 条

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