摘要
由二氧化锗与丙二胺四乙酸（Ｈ_４ｐｄｔａ）和二乙三胺五乙酸（Ｈ_５ｄｔｐａ）直接制备［Ｇｅ－（ＯＨ）（Ｈｐｔｄａ）］（Ⅰ）和［Ｇｅ（ＯＨ）（Ｈ_２ｄｔｐａ）］·Ｈ_２Ｏ（Ⅱ）。Ｘ－射线单晶结构分析证明，在这两个螯合物中，与Ｇｅ（Ⅳ）螯合的氨基多羧酸均呈五齿，由ＯＨ－占据畸变八面体的第六个配位位置。未参与配位的一个羧基形成分子间氢键，而在（Ⅱ）中还有一个自由羧基形成内盐，并与水分子共同形成分子内氢键。晶体参数：［Ｇｅ（ＯＨ）（Ｈｎｄｔａ）］（Ⅰ），Ｍ_γ＝３９２．８５，正交晶系，空间群Ｐｃａ２_１，ａ＝１５．２４８（２），ｂ＝７．０２９（２），ｃ＝１３．３８４（２），Ｖ＝１４３４．５，Ｚ＝４，Ｄ_ｃ＝１．８１９ｇ／ｃｍ~３，μ（ＭｏＫａ）＝２１．５５ｃｍ^（－１），Ｆ（０００）＝８００．用１１７２个Ｉ＞３σ（Ｉ）的独立衍射精修结构，最终偏差因子Ｒ＝０．０３３；［Ｇｅ（ＵＨ）（Ｈ_２ｄｔｐａ）］·Ｈ_２Ｏ（Ⅱ），Ｍ_γ＝４９７．９４，三斜晶系，空间群Ｐ１，ａ＝７．２３１（２），ｂ＝１０．４０７（１），ｃ＝１３．２８６（２），α＝７４．４２（１），β＝７５．３０（１），γ＝８８．１５（１）°，Ｖ＝９３０．９，Ｚ＝２。
The crystal and molecular structures of the title complexes, formed when GeO_2 was mixed with H_4pdta and H_5dtpa in hot water, have been determined by X-ray diffraction method using MoKα radiation(λ=0. 71073) at 297K.[Ge(OH)(Hpdta)](Ⅰ),M_γ=392.85,orthorhombic, Pca2_1, a=15. 248(2), b=7.029(2), c=13. 384(2),V= 1434. 5, Z=4, D_c=1.819 gcm￣(-3), μ(MoKα)=21.55cm￣(-1), F(000)=800,R=0.033 for 1172 observed reflections; [Ge(OH)(H_2dtpa)]·H_2O(Ⅱ), M_γ= 497.94, triclinic, P1,α=7.231 (2),b=10.407(1), c=13. 286(2),α=74.42(1),β=75.30(1), γ=88. 15(1)°, V=930.9, Z=2,D_c=1. 776 gcm￣(-3), μ(MoKα)=16.92 cm￣(-1),F(000)=512, final R=0.044 for 2687 observed reflections. Both complexes have an octahedral structure in which the aminopolycarboxylic acid serves as a pentadentate ligand with one acetate group protonated and free from coordination.The sixth coordination site is occupied by an OH￣- group, forming electrically neutral complexes.Besides the intermolecular hydrogen bonds formed by the free carboxylic groups in both complexes,intramolecular hydrogen bonds are also formed either by water molecule or by another free carboxylic group with zwitter-ion structure in complex(Ⅱ).
基金
国家自然科学基金
关键词
锗
配合物
氨基多羧酸
晶体结构
germanium(Ⅳ) complex
aminocarboxylic acid
crystal structure
