The title complex K [Gd~Ⅲ(edta)(H_2O)_3]·5H_2O was synthesized, where edta denotes ethylenediamine- tetraacetic acid. The crystal and molecular structure of the complex were determined by single-crystal X-ray st...The title complex K [Gd~Ⅲ(edta)(H_2O)_3]·5H_2O was synthesized, where edta denotes ethylenediamine- tetraacetic acid. The crystal and molecular structure of the complex were determined by single-crystal X-ray structure analysis. The crystal belongs to an orthorhombic crystal system and an Fdd2 space group. The complex anion [Gd~Ⅲ(edta)(H_2O)_3] has a pseudo-monocapped square antiprismatic nine-coordinate structure in which six coordinate atoms (two N and four O) are from an edta ligand and three water molecules coordinate to Gd~Ⅲ ion directly. It can be predicted that Gd~Ⅲ ion can also form a nine-coordinate complex with ttha (triethylenetetraminehexaacetic acid) li- gand, so the GdⅢ complex anion [Gd~?é¨(r)(Httha)]~￡¨2-￡(c) can supply a free non-coordinate carboxyl group (-C-CH_2COOH) used for molecular embellishment in some biological molecules to form a contrast agent of Magnetic Resonance Imagine (MRI) with targeting function.展开更多
文摘The title complex K [Gd~Ⅲ(edta)(H_2O)_3]·5H_2O was synthesized, where edta denotes ethylenediamine- tetraacetic acid. The crystal and molecular structure of the complex were determined by single-crystal X-ray structure analysis. The crystal belongs to an orthorhombic crystal system and an Fdd2 space group. The complex anion [Gd~Ⅲ(edta)(H_2O)_3] has a pseudo-monocapped square antiprismatic nine-coordinate structure in which six coordinate atoms (two N and four O) are from an edta ligand and three water molecules coordinate to Gd~Ⅲ ion directly. It can be predicted that Gd~Ⅲ ion can also form a nine-coordinate complex with ttha (triethylenetetraminehexaacetic acid) li- gand, so the GdⅢ complex anion [Gd~?é¨(r)(Httha)]~￡¨2-￡(c) can supply a free non-coordinate carboxyl group (-C-CH_2COOH) used for molecular embellishment in some biological molecules to form a contrast agent of Magnetic Resonance Imagine (MRI) with targeting function.
