The reaction of the alkyl alkylidyne W(CH2CMe3)3(=CSiMe3) (1) with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes: W3O3(μ=O)3(CH2CMe3)6(THF)3 (2) and [W303(μ=O)3(Ch2CMe3...The reaction of the alkyl alkylidyne W(CH2CMe3)3(=CSiMe3) (1) with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes: W3O3(μ=O)3(CH2CMe3)6(THF)3 (2) and [W303(μ=O)3(Ch2CMe3)6(D2O)3] 2benzene-d6 (3.2benzened6), respectively, each containing two alkyl ligands per W atom. This is in contrast to the dimer W2o(β-O)(CH2CMe3)6, containing three alkyl ligands per W atom, from the previously reported reaction of the alkyl alkylidyne analog W(CH2CMe3)3- (=-CCMe3) with H2O. In the reaction of 1 with D20 in THF, an unstable intermediate W2O2(μ-O)(CD2SiMe3)2(CH2CMe3)4 (4-d4) was identified. Kinetic studies of the reactions of 1 with excess H2O and D2O in THF-ds, yielding 4 and 4-d4, respectively, give a kinetic isotope effect (KIE) of 3.46(3) at 298(1) K, suggesting that the disappearance of 1 is a rate-determining step.展开更多
基金supported by the US National Science Foundation(CHE-0749651 & CHE-1012173)
文摘The reaction of the alkyl alkylidyne W(CH2CMe3)3(=CSiMe3) (1) with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes: W3O3(μ=O)3(CH2CMe3)6(THF)3 (2) and [W303(μ=O)3(Ch2CMe3)6(D2O)3] 2benzene-d6 (3.2benzened6), respectively, each containing two alkyl ligands per W atom. This is in contrast to the dimer W2o(β-O)(CH2CMe3)6, containing three alkyl ligands per W atom, from the previously reported reaction of the alkyl alkylidyne analog W(CH2CMe3)3- (=-CCMe3) with H2O. In the reaction of 1 with D20 in THF, an unstable intermediate W2O2(μ-O)(CD2SiMe3)2(CH2CMe3)4 (4-d4) was identified. Kinetic studies of the reactions of 1 with excess H2O and D2O in THF-ds, yielding 4 and 4-d4, respectively, give a kinetic isotope effect (KIE) of 3.46(3) at 298(1) K, suggesting that the disappearance of 1 is a rate-determining step.