Silylation reactions of olefins with monosilane and disilane in the presence of a transition metal complex, metal hydride, and radical initiator
作者:Masayoshi Itoh、Kenji Iwata、Mineo Kobayashi
DOI:10.1016/s0022-328x(98)00814-6
日期:1999.2
The catalytic reactions between monosilane or disilane and 1-hexene or 1,5-hexadiene were studied. The reactions with monosilane gave the silylated compounds in the presence of a platinum complex, LiAlH4 and a radical initiator. In the reactions with disilane, the same silylated compounds were produced in the presence of a platinum complex as in the reaction with monosilane, and disilanylated compounds
Alkenylsilane Effects on Organotitanium-Catalyzed Ethylene Polymerization. Toward Simultaneous Polyolefin Branch and Functional Group Introduction
作者:Smruti B. Amin、Tobin J. Marks
DOI:10.1021/ja057947r
日期:2006.4.1
The comonomer 5-hexenylsilane is introduced into organotitanium-mediated ethylene polymerizations to produce silane-terminated ethylene/5-hexenylsilane copolymers. The resulting polymers were characterized by 1H and 13C NMR, GPC, and DSC. High activities (up to 107 g polymer/(mol Ti.atm ethylene.h)) and narrow polydispersities are observed in the polymerization/chain transfer process. Ethylene/5-hexenylsilane copolymer molecular weights are found to be inversely proportional to 5-hexenylsilane concentration, supporting a silanolytic chain transfer mechanism. Control experiments indicate that chain transfer mechanism by 5-hexenylsilane is significantly more efficient than that of n-hexylsilane for organotitanium-mediated ethylene polymerization. The present study represents the first case in which a functionalized comonomer is efficiently used to effect both propagation and chain transfer chemistry during olefin polymerization.