Removal of Metal−Metal Bonding in a Dimetallic Paddlewheel Complex: Molecular and Electronic Structure of Bis(phenyl) Dirhodium(III) Carboxamidate Compounds
作者:Joffrey Wolf、Rinaldo Poli、Jian-Hua Xie、Jason Nichols、Bin Xi、Peter Zavalij、Michael P. Doyle
DOI:10.1021/om800631b
日期:2008.11.24
tetracarboxamidatodirhodium(III) are reported, and their electronic structures are mapped through XPS, electrochemical, and computational methods. Comparison with the structures of dirhodium(II,II) and dirhodium(II,III) oxidative precursors portrays the diphenyl dirhodium(III) compounds as two square-pyramidal rhodium units that have undergone conrotatory motion in order to optimize metal−ligand bonding. Axial
报道了双(苯基)四甲酰胺基二ho(III)的独特结构特征和化学稳定性,并通过XPS,电化学和计算方法绘制了它们的电子结构图。与dirhodium(II,II)和dirhodium(II,III)氧化前体的结构比较,将二苯基dirhodium(III)化合物描绘为经历了旋转运动以优化金属-配体键合的两个方形金字塔形铑单元。轴向苯基配体严重偏离了其预期的Rh-Rh-C线性阵列。该系列吡啶鎓化合物的XPS数据与二苯基吡啶鎓(III)化合物不存在铑-铑键一致,并且电化学测量显示单个可逆Rh 2 6+ / Rh 27+氧化还原对。值得注意的是,它们表现出高的热稳定性,并且在苯的形成之前先去除氨基甲酸酯配体的布朗斯台德酸。通过对双-σ-(苯基)-四-μ- (羧酰胺基)dir(III)的电子结构的理论分析来解释苯基赋予铑(III)化合物非同寻常的稳定性的能力,并进行了比较。与先前报道的二亚硝酰二铑(II