Vanadium(III) complexes with the hexadentate ligand, tetramethylenediamine-N,N,N′,N′-tetraacetate (tmdta), N,N′-bis(2-pyridylmethyl)-1,2-ethanediamine-N,N′-diacetate (bpedda), and N,N′-bis(2-pyridylmethyl)-1,3-propanediamine-N,N′-diacetate (bppdda), have been prepared. The structures of the tmdta (1) and bpedda (3) complexes have been determined by X-ray crystallography. The stereochemical property of complex 1 was compared with that of the corresponding Cr(III) complex (2), whose structure was also determined by X-ray crystallography. The tmdta complexes adopt a distorted octahedral structure, including a seven-membered chelate ring formed by the tetramethylenediamine moiety of the tmdta ligand. The bpedda complex has been determined to be a heptacoordinate complex with a distorted pentagonal bipyramidal geometry. The isolated bppdda complex has been characterized to be a μ-oxo dinuclear vanadium(III) complex on the basis of its spectral features. The tmdta and bpedda complexes do not yield a corresponding μ-oxo dinuclear vanadium(III) complex on base hydrolysis.
钒(III)与六齿
配体、
四亚甲基二胺-N,N,N',N'-四
乙酸盐(tmdta)、N,N'-双(2-
吡啶基甲基)-1,2-
乙二胺-N,N'-的配合物已经制备了二
乙酸酯(bpedda)和N,N'-双(2-
吡啶基甲基)-
1,3-丙二胺-N,N'-二
乙酸酯(bppdda)。 tmdta (1) 和 bpedda (3) 配合物的结构已通过 X 射线晶体学确定。将配合物 1 的立体
化学性质与相应的 Cr(III) 配合物 (2) 进行了比较,后者的结构也通过 X 射线晶体学确定。 tmdta配合物采用扭曲的八面体结构,包括由tmdta
配体的
四亚甲基二胺部分形成的七元螯合环。 bpedda 配合物已被确定为具有扭曲的五角双锥几何形状的七配位配合物。根据其光谱特征,分离的 bppdda 络合物被表征为 μ-氧双核
钒 (III) 络合物。 tmdta 和 bpedda 配合物在碱
水解时不会产生相应的 μ-氧双核
钒 (III) 配合物。