Synthesis and Coordination Chemistry of a Tridentate o-Phenylene-Bridged Diphosphine−NHC System

The preparation of a di-o-phenylene-bridged tridentate PCP donor set is described starting with t-BOC-aniline followed by a series of steps that include lithiation, quenching with Pri2PCl, conversion to the phosphine sulfide, and assembling the unsaturated N-heterocyclic carbene unit. After desulfurization, the imidazolinium unit flanked by two phosphine units, represented as [(PCP)H]PF6 is obtained. Subsequent reaction with group 10 M(0) reagents (Ni(COD)2, Pd(PPh3)4, and Pt(PPh3)4) generates good yields of the corresponding metal hydride complexes, [(PCP)MH]PF6 salts (where M = Ni(II), Pd(II), and Pt(II)). Each of these species has been characterized by elemental analyses, NMR spectroscopy, and X-ray crystallography. All of the structures show that the PCP unit is twisted with respect to the square plane of the d8 metal complex.

本文详细描述了一种以t-BOC-苯胺为起始原料，通过一系列包括锂化、使用二碘化亚磷酰铯淬灭、转化为膦硫化合物以及构建不饱和N-杂环卡宾单元的步骤，制备双苯基-桥连三齿PCP供体集的过程。经过脱硫处理，得到由两个膦基单元夹持的咪唑啉鎓单元，并以[(PCP)H]PF6的形式呈现。随后的与第10族M(0)试剂（Ni(COD)2、Pd(PPh3)4和Pt(PPh3)4）的反应，生成了相应的金属氢化物复合物盐[(PCP)MH]PF6（其中M = Ni(II)、Pd(II)和Pt(II)），并取得了良好的产率。通过元素分析、核磁共振波谱学和X射线晶体学对这些物种进行了表征。所有结构均显示PCP单元相对于d8金属复合物的正方形平面发生扭曲。