Bond-valence Approach to the Semicoordination in Seven-Coordinated Copper(II) Complexes with 4-Aminopyridine:Crystal and Molecular Structure of Bis(4-aminopyridine)di(acetato)(aqua)copper(II)

摘要

The structure of [Cu(CH_3COO)_2(4-aminopyridine)_2(H_2O)] was X-ray studied.Heptacoordinated copper atoms of [Cu(CH_3COO)_2(4-aminopyridine)_2(H_2O)] complex are consistent with bond valence sum model based on orbital metal-ligand interaction.Equatorial plane of deformed tetragonal bipyramid as copper coordination polyhedron is formed by atoms O of carboxylato ligands and water molecule.Two N atoms of 4-aminopyridine molecules occupy the axial sites.Each copper atom is semicoordinated by two atoms O from two carboxylato chelates.The lengths of two semicoordinated Cu...O bonds are 3.041(2) A (twice).Seven-coordinated copper atom of the studied compound and Cu(oxalato)(H_2O) (4-aminopyridine)_2 is consistent with the bond valence sum model.