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烷基卡宾化合物W(CH2CMe3)3(/CSiMe3)(1)与水在四氢呋喃(THF)中,或者与重水在苯-d6中的反应分别生成两个新的含氧配体的三聚物W3O3(μ=O)3(CH2CMe3)6(THF)3(2)和[W3O3(μ=O)3(CH2CMe3)6(D2-O)3]·2benzene-d6(3·2benzene-d6).这两个产物中每个钨原子均含两个烷基配体,与以前报道过的从类似的烷基卡宾化合物W(CH2CMe3)3(/CCMe3)与水反应所生成的二聚物W2O2(μ-O)(CH2CMe3)6有很大不同.化合物1与重水在四氢呋喃的反应中,观测到一个不稳定的中间体W2O2(μ-O)(CD2SiMe3)2(CH2CMe3)4(4-d4).对1与水或者与重水在THF-d8中的反应生成4及4-d4进行了动力学研究,在298(1)K,动力学同位素效应(KIE)为3.46(3),显示1的消失是一个速率决定步骤.
Reaction of alkylcarbene compound W (CH2CMe3) 3 (/ CSiMe3) (1) with water in tetrahydrofuran (THF), or with heavy water in benzene-d6 yielded two new ternary ligands, W3O3 (μ = O) 3 (CH2CMe3) 6 (THF) 3 (2) and [W3O3 (μ = O) 3 (CH2CMe3) 6 (D2-O) 3] · 2benzene-d6 (3.2 · benzene- d6) Each of the two products contains two alkyl ligands per tungsten atom, which is similar to the previously reported dimer W2O2 (μ (2), produced from the reaction of a similar alkyl carbene compound W (CH2CMe3) 3 (/ CCMe3) -O) (CH2CMe3) 6 An unstable intermediate W2O2 (μ-O) (CD2SiMe3) 2 (CH2CMe3) 4 (4-d4) was observed in the reaction of compound 1 with heavy water in tetrahydrofuran. Kinetic studies of the formation of 4 and 4-d4 by reaction of 1 with water or with heavy water in THF-d8 showed a kinetic isotopic effect (KIE) of 3.46 (3) at 298 (1) K, indicating the disappearance of 1 Is a rate decision step.