Formation and Redox Interconversion of Niobium Methylidene and Methylidyne Complexes.
Formation and Redox Interconversion of Niobium Methylidene and Methylidyne Complexes.
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亚甲基铌和亚甲基铌配合物的形成和氧化还原互变。
DOI：
10.1002/anie.201511867
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发表时间：
2016
影响因子：
--
通讯作者：
D. Mindiola
中科院分区：
文献类型：
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作者：
K. Searles;Kyle T. Smith;T. Kurogi;Chun;P. Carroll;D. Mindiola
甲基铌[{(Ar' o) 2nb}2 (μ2 -Cl)2 (μ2 -CH2)](2)可通过[(Ar' o) 2nb (CH3) 2cl] (1) （OAr'=2,6-双（二苯基甲基）-4-叔丁基苯氧化合物）的热分解或光解制备。用两个等价物KC8还原2，通过双核α-氢消除反应生成第一个铌甲基炔[K][{(Ar'O) 2nb}2 (μ2 -CH)(μ2 -H)(μ2 -Cl)](3)。用两个等量的ClCPh3重整物氧化3。除了固态x射线分析外，所有这些配合物都通过多核磁共振实验和同位素标记研究（包括交叉实验）进行了阐明，支持了自由基机制的概念，以及双核α-氢提取途径在1生成2的过程中起作用。
The niobium methylidene [{(Ar'O)2 Nb}2 (μ2 -Cl)2 (μ2 -CH2 )] (2) can be cleanly prepared via thermolysis or photolysis of [(Ar'O)2 Nb(CH3 )2 Cl] (1) (OAr'=2,6-bis(diphenylmethyl)-4-tert-butylphenoxide). Reduction of 2 with two equivalents of KC8 results in formation of the first niobium methylidyne [K][{(Ar'O)2 Nb}2 (μ2 -CH)(μ2 -H)(μ2 -Cl)] (3) via a binuclear α-hydrogen elimination. Oxidation of 3 with two equiv of ClCPh3 reforms 2. In addition to solid state X-ray analysis, all these complexes were elucidated via multinuclear NMR experiments and isotopic labelling studies, including a crossover experiment, support the notion for a radical mechanism as well as a binuclear α-hydrogen abstraction pathway being operative in the formation of 2 from 1.