An Imidazolate‐ and Azide‐Bridged Copper(II) Coordination Polymer Consisting of Alternating Di‐ and Mononuclear Units

Abstract

Using the CuII‐imidazole(Him) complex [Cu(Him)4Cl]Cl as the starting material, the imidazolate (im)‐ and azide‐bridged CuII coordination polymer [Cu3(Him)4(im)2(N3)4]n was successfully obtained. Single‐crystal X‐ray analysis revealed that it possesses an im‐bridged linear‐chain structure consisting of alternating dinuclear units with a symmetric end‐on azide‐bridged [Cu(μ1,1‐N3)2Cu]2+ core and mononuclear units. All of the Cu ions adopt a square pyramidal geometry with an azide at the Jahn–Teller elongated apical position. Some of the azides act as end‐to‐end interchain bridging ligands from the mononuclear unit to the nearest neighbouring dinuclear unit of the adjacent chain forming a two‐dimensional network. Temperature‐variable magnetic susceptibility measurements showed that it exhibits one‐dimensional ferrimagnetic‐like behaviour, which can be ascribed to two types of exchange couplings with opposite signs, namely a weak ferromagnetic coupling through the end‐on azide bridges within the dinuclear units and a stronger antiferromagnetic coupling through the im bridges between the di‐ and the mononuclear units.

Chain of dimers to assembly of trimers: temperature and ligand influenced formation of novel supramolecular assemblies of Cu(ii) with isomeric (aminomethyl) pyridines and azide

“…Among all the metal ions studied, the Cu(II)-azide system is quite versatile as it yielded several dimeric and multidimensional assemblies exhibiting ferro-, 5a,c-e anti-ferro, 5b ferri, 12 meta-magnetism, 13 spin canting, 14 spin flop 13 and single molecule magnetism. 15 Azide can adopt diverse bridging modes, viz., m 1,1 , m 1,3 , m 1,1,1 , m 1,1,3 , m 1,1,1,1 and m 1,1,3,3 .…”