Two novel bimetallic transition metal–uranyl one-dimensional coordination polymers with manganese(II) and cobalt(II) incorporating bridging diglycolate (2,2′-oxydiacetate) ligands

Abstract

The crystal structures of two new bimetallic uranyl–transition metal compounds with diglycolic acid [or 2-(carboxymethoxy)acetic acid] have been hydrothermally synthesized and structurally characterized via single-crystal X-ray diffraction. The compounds, namely catena-poly[[[tetraaquamanganese(II)]-μ-2,2′-oxydiacetato-[dioxidouranium(VI)]-μ-2,2′-oxydiacetato] dihydrate], {[MnU(C4H4O5)2O2(H2O)4]·2H2O} n , and catena-poly[[[tetraaquacobalt(II)]-μ-2,2′-oxydiacetato-[dioxidouranium(VI)]-μ-2,2′-oxydiacetato] dihydrate], {[CoU(C4H4O5)2O2(H2O)4]·2H2O} n , both crystallize in the triclinic space group P\overline{1}. These compounds form one-dimensional chains via alternating uranyl and transition metal building units. The chains then assemble into three-dimensional supramolecular networks through several hydrogen bonds between water molecules and diglycolate ligands. Luminescence measurements were conducted and no uranyl emission was observed in either compound.