Potential catalyst deactivation reaction in homogeneous Ziegler-Natta polymerization of olefins: Formation of an allyl intermediate

被引：61

作者：

Margl, PM ^{[1
]}

Woo, TK ^{[1
]}

Ziegler, T ^{[1
]}

机构：

[1] Univ Calgary, Dept Chem, Calgary, AB T2N 1N4, Canada

来源：

ORGANOMETALLICS | 1998年 / 17卷 / 23期

关键词：

D O I：

10.1021/om980424q

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

We investigate the possibility of premature deactivation of d(0) transition metal Ziegler-Natta metallocene catalysts Cp'2MR+ (Cp' = any cyclopentadienyl derivative) used in homogeneous olefin polymerization. Density functional calculations show that beta-hydride elimination from the P-agostic precursor likely leads to formation of an allyl dihydrogen complex. This complex is prone to eject the dihydrogen ligand and form a "torpid" Cp'M-2 (allyl)(+) complex that can be slow to restart chain propagation, depending on the steric hindrance imposed on the metal by the Cp' moiety. Our theoretical observations are in line with previous experimental evidence for such a reaction.

引用

页码：4997 / 5002

页数：6

共 30 条

[1] Self-consistent molecular Hartree-Fock-Slater calculations - I. The computational procedure [J].