Amino-functionalized zirconocene (C 5H 4CH(Me)NMe 2) 2ZrCl 2, a catalyst for the dehydropolymerization of PhSiH 3: Probing of peripheral substituent effects on catalyst dehydropolymerization activity

• Published in: Inorganica Chimica Acta Vol. 330; no. 1; pp. 89 - 94
• Main Authors: Grimmond, Brian J, Corey, Joyce Y
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2002
• Subjects: Dehydrocoupling; Metallocenes; Phenylsilane; Poly(phenylsilane); Dehydrocoupling; Phenylsilane; Metallocenes; Poly(phenylsilane)
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/S0020-1693(01)00738-1

The amino-functionalized metallocene (C 5H 4CH(Me)NMe 2) 2ZrCl 2, [(Cp N) 2ZrCl 2] was synthesized by salt metathesis of ZrCl 4 and 2 equiv. of C 5H 4CH(Me)NMe 2Li. The metallocene was obtained in good yield as a mixture of rac and meso diastereomers as established by NMR spectroscopy. The addition of 2 equiv. of n-BuLi to the metallocene (Cp N) 2ZrCl 2 produced a co-catalyst system which was active, at a 1.0 mol% loading, in the dehydropolymerization of PhSiH 3 to poly(phenylsilane), PPSi. The PPSi was obtained as a 9:1 linear–cyclic mixture ( M w=3850, M n=2300) as established by GPC analysis; 29Si{ 1H} NMR spectroscopy revealed an atactic polymer microstructure. The amino-functionalized zirconocene dichloride, (C 5H 4CH(Me)NMe 2) 2ZrCl 2, was activated towards the dehydropolymerization of PhSiH 3 when mixed with 2 equiv. of n-BuLi. The molecular weight properties and tacticity of the polysilane were used to evaluate any role of the amine functional group on the dehydrocoupling mechanism.