Heterobinuclear and Heterotrinuclear complexes of Oxorhenium(V) with Cu(II), Ni(II), Fe(III), UO2(VI) and Th(IV) in the solid state

Abstract

New heteronuclear complexes containing oxorhenium(V), Cu(II), Ni(II), Fe(III), UO2(VI) and Th(IV) ions were prepared by the reaction of the complex ligand, [ReO(H4L)Cl]Cl2, where H4L = 8,17-dimethyl-6,15-dioxo-5,7,14,16-tetrahydrodibenzo[a,h][14]annulene-2,11-dicarboxylic acid, with the previous transition and actinide salts. Three heteronuclear Cu(II) complexes were isolated depending on the ratio of [ReO(H4L)Cl]Cl2 : Cu(II) ion. When the ratios were 1 : 0.5, 1 : 1 and 1 : 2, the heteronuclear complexes {[ReO(H3L)Cl]2CuCl2(OH2)2}SO4 · H2O (I), [ReO(H3L)Cl2Cu(OH2)2(SO4)] (II) and {ReO(H2L)Cl[Cu(OH2)3 SO4]2} (III) were obtained, respectively. Heteronuclear complexes of the other metal cations were obtained by mixing [ReO(H4L)Cl]Cl2 with the metal salt in the ratio 1 : 1 to obtain the heteronuclear complexes [ReO(H3L)Cl2Ni(OH2)2](NO3)2 (IV), [ReO(H3L)Cl3Fe(OH2)3](NO3)2 (V), [ReO(H3L)ClUO2(NO3)2 (OH2)]Cl (VI) and [ReO(H3L)Cl3Th(NO3)2(OH2)]NO3 · 2H2O (VII). The complex ligand coordinates with the heterometal ion via the carboxylate group, and the infrared bands νas COO and νs COO indicate that the carboxylate acts as a unidentate ligand to the heterometal cations. Cu(II) and Fe(III) cations in the heteronuclear complexes have octahedral geometry, while Ni(II) is square planar. Thermal studies explored the possibility of obtaining new heteronuclear complexes pyrolytically in the solid state from the corresponding mother complexes. The structures of the complexes were elucidated by conductance, IR and electronic spectra, magnetic moments, 1H NMR and TG-DSC measurements as well as by mass spectroscopy.