Alkyl Substituent Effects on Reductive Elimination Reactions in Zirconocene Alkyl Hydride Complexes. Manipulation of the Alkyl Steric Environment Allows the Synthesis of a Zirconocene Dinitrogen Complex
作者:Jaime A. Pool、Emil Lobkovsky、Paul J. Chirik
DOI:10.1021/om0302239
日期:2003.6.1
incorporated into the metallocene framework. Thus, the Cp*Cp‘ ‘‘Zr(R)H (Cp‘ ‘‘ = η5-C5H2-1,2,4-(SiMe3)3, R = CH3, CH2(CH2)2CH3, CH2(CH2)6CH3) series of alkyl hydride complexes lose alkane more readily than the corresponding Cp*Cp‘ ‘Zr(R)H complexes. In addition, the rate of reductive elimination has also been examined for Cp*Cp‘ ‘Zr(Ph)(H) and Cp*Cp‘ ‘Zr(CH2Ph)H (Ph = C6H5) and is slower than the alkyl hydride
还原消除如烷基配体的功能的速度已经进行了一系列锆烷基氢化物络合物中,Cp * Cp的“被测量“的Zr(R)H(CP * =η 5 -C 5我5中,Cp” =η 5 -C 5 H 3 -1,3-(SiMe 3)2,R = CH 3,CH 2(CH 2)2 CH 3,CH 2(CH 2)6 CH 3,CH 2 cC 6 H 11,CH 2 CHMe 2,CH 2 CMe 3),其中烷基配体的空间位置已被系统地改变。还原消除的速率随着烷基配体的空间体积的增加而适度地增加。该趋势归因于烷基配体与环戊二烯基取代基之间不利的空间相互作用而引起的基态不稳定。当更多量的环戊二烯基配体被结合到茂金属骨架中时,该效果被放大。因此,在CP * CP ' ''的Zr(R)H(CP' ''=η 5 -C 5 H ^ 2 -1,2,4-(森达3)3,R = CH 3,CH 2(CH 2)2 CH 3,CH 2(CH 2)6