摘要:
Two mixed-ligand complexes of copper(II) azide with substituted pyridines, namely catena-di-mu(1,3)-azido[di-mu(1,1)-azido-tetrakis(3-picoline)dicopper(II)] (1) and catena-di-mu(1,1)-azido[di-mu(1,1)-azido-bis(2-bromopyridine)dicopper(II)] (2), have been synthesized and characterized by X-ray crystallography. The 1:2 polymeric complex 1 contains two crystallographically independent copper octahedra. Cu(1) occupies the special position at the inversion centre, and both copper centres have a (4 + 2) coordination with four short bonds [Cu-N from 1.970 to 2.030 angstrom] and two long bonds [Cu-N from 2.625 to 2.679 angstrom]. Cu(1) and Cu(2) are linked via two mu(1,3)-azido ligands, whereas azido groups of the type mu(1,1) bridge the adjacent Cu(2)-Cu(2) centres. In the polymeric 1:1 complex 2 of 2-bromopyridine the copper(II) has distorted square pyramidal coordination geometry, where both azido ligands function as mu(1,1) bridges to form chains along the crystallographic a-axis. The IR and electronic spectra are given and discussed.