Synthesis, characterization, and structures of two new tetranuclear copper complexes with azido/dicyanamide bridges containing chiral Schiff base ligand

Abstract

Two new copper complexes [Cu4(μ-L)2(μ1,1-N3)2(N3)2] (I) and [Cu4(μ-L)2(μ1,5-Dca)2(Dca)2] (II) (H2L = (1R,3S)-N′,N″-bis[5-methoxysalicylidene]-1,3-diamino-1,2,2-trimethylcyclopentane, Dca = dicyanamide ions) were synthesized and structurally characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction (CIF files CCDC nos. 1013673 (I), 1013672 (II)). The two complexes crystallize in monoclinic P21/c and triclinic $P\bar 1$ space group, respectively. Both the complexes consist of two crystallographically independent copper ions connected by a double phenoxo bridges, which are further linked to the other symmetry-related half of the molecule by two end-on azido bridges or μ1,5-dca groups.