Synthesis of <i>cis</i>- and <i>trans</i>-Diisothiocyanato−Bis(NHC) Complexes of Nickel(II) and Applications in the Kumada−Corriu Reaction
作者:Ramasamy Jothibasu、Kuo-Wei Huang、Han Vinh Huynh
DOI:10.1021/om100241v
日期:2010.9.13
Metathetical reaction of AgSCN with a series of trans-dihalido-bis(carbene) nickel(II) complexes in CH3CN readily afforded the novel diisothiocyanato-bis(carbene) complexes [Ni(NCS)2(NHC)2] (trans-2a, NHC = 1,3-diisopropylbenzimidazolin-2-ylidene; trans-2b, NHC = 1,3-diisobutylbenzimidazolin-2-ylidene; trans-2c, NHC = 1,3-dibenzylbenzimidazolin-2-ylidene; cis-2d, NHC = 1,3-di(2-propenyl)benzimidazolin-2-ylidene;
AgSCN与CH 3 CN中的一系列反式-二卤代-双(卡宾)镍(II)配合物间的易位反应提供了新型的二异硫氰酸根合-双(卡宾)配合物[Ni(NCS)2(NHC)2 ](反-图2a,NHC = 1,3- diisopropylbenzimidazolin -2-亚基;反式-2b,NHC = 1,3- diisobutylbenzimidazolin -2-亚基;反式-2℃,NHC = 1,3- dibenzylbenzimidazolin -2-亚基;顺式- 2D, NHC = 1,3-二(2-丙烯基)benzimidazolin -2-亚基;顺式- 2E,NHC = 1-丙基-3-甲基苯并咪唑啉-2-亚基)为浅黄色至浅黄色粉末,产率中等至良好。而dihalido双(卡宾)的Ni(II)络合物只形成反-complexes,一个反式-顺式异构化发生在与复合物轴承体积较小碳烯配体,即,halido异硫氰酸根交换顺式2D