Features of Cadmium(II) Complexation with N-Donor Heterocyclic Ligands in the Presence of the Octadecahydroeicosaborate Anion

Abstract

The process of cadmium(II) complexation with 1-ethyl-2-(4-methoxyphenyl)azobenzimidazole (L1), 2,2′-bipyridyl (L2), and 1,10-phenanthroline (L3) in the presence of the [trans-B20H18]2– anion has been studied. It has been found that the nature of the organic ligand affects the composition and structures of the resulting compounds. Complexation with ligand L1, a benzimidazole derivative, has yielded binuclear complex [CdL12NO3(μ-NO3)CdL1(NO3)2] (1), which contains no boron cluster anion. In the case of azaheterocyclic ligands L2 and L3, depending on the Cd : L ratio, heteroleptic complexes [CdL2NO3]2[trans-B20H18] (L = L2 (2); L3 (3)) with coordinated nitrate ions (Cd : L = 1 : 2) or tris-chelate complexes [CdL3][trans-B20H18] (L = L2 (4); L3 (5)) with the boron cluster anion as a counterion (Cd : L = 1 : 3) have been isolated. The structures of complexes [CdL12NO3(μ-NO3)CdL1(NO3)2] (1) and [Cd(L2)2NO3]2[trans-B20H18] (2) have been determined by X-ray diffraction.