화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.134, No.22, 9154-9156, 2012
Nonclassical beta-Hydrogen Elimination of Hydrosilazido Zirconium Compounds via Direct Hydrogen Transfer
Salt metathesis reactions of Cp-2(NR2)ZrX(X = Cl, I, OTf) and lithium hydrosilazides ultimately afford hydride products Cp-2(NR2)ZrH that suggest unusual beta-hydrogen elimination processes. A likely intermediate in one of these reactions, Cp2Zr[N(SiHMe2)t-Bu][N(SiHMe2)(2)], is isolated under controlled synthetic conditions. Addition of alkali metal salts to this zirconium hydrosilazide compound produces the corresponding zirconium hydride. However as conditions are varied, a number of other pathways are also accessible, including C-H/Si-H dehydrocoupling, gamma-abstraction of a CH, and beta-abstraction of a SiH. Our observations suggest that the conversion of (hydrosilazido)zirconocene to zirconium hydride and silanimine does not follow the classical four-center mechanism for beta-elimination.