几种膦铑络合物及其MAC络合物的量子化学计算

A Quantum Chemistry Calculation of the Rh(I)-Methyl-α-AcetamidocinnamateComplexes with Diphosphine Ligands

采用从头计算方法 (HF)对几种膦铑络合物 [Rh(R ,R) -DIPAMP]+,[Rh(S ,S) -CHI RAPHOS]+,[Rh(DIPHOS) ]+及它们与乙基 -α -乙酰胺基肉桂酸 (MAC)结合形成的中间体 [Rh(R ,R -DIPAMP) (MAC) ]+,[Rh (S ,S -CHIRAPHOS) (MAC) ]+,[Rh(DIPHOS) (MAC) ]+的几何结构进行了优化 ,计算结果显示 :( 1 )采用从头计算方法对含有膦铑络合物的较大催化体系的全优化计算是可行的 ;( 2 )分子构型不同的双膦配体及其所形成的膦铑络合物中大部分主要原子间的键长、键角数据相差不大 ,但手性的不同对膦铑络合物的部分键长、键角数据有所影响 ;( 3)在与 (MAC)形成络合物前后 ,双膦配体上主要原子的电荷分布变化并不显著 ,但金属铑原子上的电荷则显著增加 。

A theoretical study on Rh(I)-methyl-α-acetamidocinnamate complexes with diphosphine ligands is presented. The geometrical optimizations are performed at the ab initio level, and the geometry optimized results indicate:(1) quantum chemical method can be used in the optimization of the intermediates of this kind of reactions; (2) There are no significant differences in the long distances and bond angel among the Rh(I)-methyl-α-acetamidocinnamate complexes with different diphosphine ligands, but the bond angel may be affected by the chiral of the disphosphine ligands; (3) There are no significant changes in the charge on the main atoms of diphosphine ligands after becoming the complexes with MAc, but the charge on the Rh increases, which may transfer from the MAC.