Nickel(0)-induced geminal bond cleavages leading to carbon-carbon double bonds: Intermediacy of nickel(0)-carbene complexes as a unifying hypothesis
Nickel(0)-induced geminal bond cleavages leading to carbon-carbon double bonds: Intermediacy of nickel(0)-carbene complexes as a unifying hypothesis
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DOI：
10.1016/0022-328x(95)05948-o
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发表时间：
1996-04-19
影响因子：
2.3
通讯作者：
Singh, M
中科院分区：
文献类型：
--
作者：
Eisch, JJ;Qian, Y;Singh, M
在R（2）CE（2）和R（2）C=E型单体与配合物（Cod）（2）Ni、（Et（3）P）（4）Ni和（Bpy）（Cod）Ni之间的化学计量反应中，以及在α-锂有机砜的镍（0）-催化α-消除反应中，研究了用镍（0）配合物实现有机单体的孪键断裂以获得烯属二聚体的可能性，RR'C（Li）（SO（2）R“）。偕键的化学计量裂解底物包括偕二卤代物、氨甲基硫醚、环丙烯、硫酮和酮。在大多数情况下，包括α-锂有机砜的催化分解，烯烃或其羟基衍生物的还原二聚反应都不同程度地发生。因此，这种方法在有机合成中具有相当大的前景。一个已知的镍（0）化学，化学捕获和光谱证据的结果整理支持的建议，这种偕键裂解和还原偶联过程最有可能进行通过镍（0）-卡宾中间体的类型R（2）C=Ni。L（n）.
The possibility of effecting geminal bond cleavages of organic monomers with nickel(0) complexes to achieve olefinic dimers has been investigated both in stoichiometric reactions between monomers of the type R(2)CE(2) and R(2)C=E and the complexes (Cod)(2)Ni, (Et(3)P)(4)Ni and (Bpy)(Cod)Ni and in nickel(0)-catalytic alpha-elimination reactions of alpha-lithioorganic sulfones, RR'C(Li)(SO(2)R ''). Substrates for the stoichiometric geminal bond cleavages comprised geminal dihalides, aminomethyl sulfides, cyclopropenes, thioketones and ketones, Reductive dimerization to the olefin or its hydroxy derivatives was found to occur to a varying degree in most cases, including the catalytic decomposition of the alpha-lithioorganic sulfones, Accordingly, this method offers considerable promise in organic synthesis. A gamut of known nickel(0) chemistry, results of chemical-trapping and spectroscopic evidence are marshaled in support of the proposal that such geminal bond cleavages and reductive coupling processes most likely proceed via nickel(0)-carbene intermediates of the type R(2)C=Ni . L(n).