Preparation, Spectral and Structural Characterization of Two Polymeric 1:1 Mixed Ligand Complexes of Copper(II) Azide with 4-Methylquinoline and 2-Methylpyridine

Abstract

Two 1:1 mixed ligand complexes of copper(II) azide with substituted quinoline and pyridine, namely catena di-μ(1,1)-azido-(4-methylquinoline)copper(II) (1) and catena di-μ(1,3)-azido-[di-μ(1,1)-azido-bis(2-methylpyridine)dicopper(II)] (2) have been prepared and characterized by X-ray crystallography. Crystal data: 1, C10H9N7Cu, space group P21/c, a = 577.8(2), b = 2202.3(5), c = 919.9(2) pm, β = 93.92(2)°, Ζ = 4, and R = 0.035 for 1293 observed MoKa data; 2, C6H7N7Cu, space group P21/a, a = 823.7(2), b = 1303.8(4), c = 895.3(3) pm, β = 112.23(2)°, Ζ = 4, and R = 0.022 for 2133 observed ΜοΚα diffractometer data. In the structure of 1, the Cu(II) has a strongly distorted trigonal bypyramidal coordination, where both azido groups function as μ(1,1) bridging ligands resulting in a columnar structure along the a axis. The polymeric complex 2 has a less distorted square pyramidal structure; one half of the azide groups act as μ(1,1) bridging ligands to form centrosymmetric dimers. These dimeric units are further connected by the remaining μ(1,3) bridging azido groups to form layers within the ab-plane. Infrared and electronic spectral data are also presented and discussed.