Synthesis and molecular structures of titanocene, zirconocene, and uranocene dichlorides containing 1,2-di-tert-butylcyclopentadienyl ligands

被引：20

作者：

Hughes, RP ^{[1
]}

Lomprey, JR ^{[1
]}

Rheingold, AL ^{[1
]}

Haggerty, BS ^{[1
]}

Yap, GPA ^{[1
]}

机构：

[1] UNIV DELAWARE,DEPT CHEM,NEWARK,DE 19716

来源：

JOURNAL OF ORGANOMETALLIC CHEMISTRY | 1996年 / 517卷 / 1-2期

基金：

美国国家科学基金会;

关键词：

titanium; zirconium; uranium; cyclopentadienyls; fluxional molecules;

D O I：

10.1016/0022-328X(96)06114-1

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The 1,2-di-tert-butylcyclopentadienyl anion (1) has been used to prepare 1,1',2,2'-tetra-tert-butyltitanocene dichloride (5), 1,1',2,2'-tetra-tert-butylzirconocene dichloride (6), and 1,1',2,2'-tetra-tert-butyluranocene dichloride (7), The bent metallocene structures of 5-7 have been confirmed by X-ray crystallography, and illustrate that the 1,2-di-tert-butylcyclopentadienyl ligands are arranged with all four tert-butyl groups in the open part of the wedge between the two canted cyclopentadienyl rings, but that steric interactions between the substituents afford a conformationally dictated C-2 symmetry for the molecules, In solution compounds 5 and 6 exhibit NMR spectra consistent with a facile dynamic process involving exchange between tert-butyl sites that are inequivalent in the solid state. The nature of this site exchange is discussed, and comparisons are made with related metallocene dichlorides of Group 4 metals.

引用

页码：89 / 99

页数：11

共 28 条

[1] STEREOSPECIFIC OLEFIN POLYMERIZATION WITH CHIRAL METALLOCENE CATALYSTS [J].