Thermolysis of Half-Sandwich Vanadium(V) Imido Complexes to Generate Vanadium(III) Imido Species via a Vanadium(IV) Intermediate

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• 作者：Aurora A. Batinas ; Jeroen Dam ; Auke Meetsma ; Bart Hessen ; Marco W. Bouwkamp
• 刊名：Organometallics
• 出版年：2010
• 出版时间：December 13, 2010
• 年：2010
• 卷：29
• 期：23
• 页码：6230-6236
• 全文大小：875K
• 年卷期：v.29,no.23(December 13, 2010)
• ISSN：1520-6041

文摘

Thermolysis of half-sandwich vanadium imido complexes Cp(RN)V(i-Pr₂N)Me (R = p-Tol, 1a; R = t-Bu, 1b) results in a mixture of products, including vanadium(IV) dimers [CpVMe]₂(μ-RN)₂, i-Pr₂NH, i-PrNCMe₂, CH₄, and one or more paramagnetic species. In the presence of dmpe (dmpe = bis(dimethylphosphino)ethane), PMe₃, or PhSSPh, the initially formed paramagnetic species can be trapped, providing Cp(RN)VL₂ (R = p-Tol, L₂ = dmpe, 2a; R = t-Bu, L₂ = dmpe, 2b; R = p-Tol, L = PMe₃, 3a; R = t-Bu, L = PMe₃, 3b; R = t-Bu, L = SPh, 4b). This suggests that the initially formed species is [Cp(RN)V]. When generated in situ, [Cp(RN)V] is active in the [2+2+2] cyclotrimerization of PhCCH (R = p-Tol, t-Bu) and PhCCPh (R = t-Bu). Furthermore, the data presented indicate a mechanism in which both [CpVMe]₂(μ-RN)₂ and [Cp(RN)V] originate from a common intermediate, vanadium(IV) imido species [Cp(RN)VMe].