Cu(II)/Cu(II)-Mg(II) containing pyridine-2,5-dicarboxylate frameworks: Synthesis, structural diversity, inter-conversion and heterogeneous catalytic epoxidation

Abstract

Ligand concentration dependent structural diversity and inter-conversion of hydrothermally synthesized metal carboxylate compounds, {[Mg(H2O)6][Cu(pdc)2]·2H2O}n (1), {[CuMg(pdc)2(H2O)4]·2H2O}n (2), {2(Him)·[Cu(pdc)2]}n (3), and {[Cu(pdc)(im)2]·2H2O}n (4) (H2Pdc = pyridine-2,5-dicarboxylic acid and im = imidazole), have been thoroughly investigated. Formation of compounds 1–4 depends on the concentration of imidazole. Structure of all four compounds has been verified by single crystal X-ray diffraction and other physicochemical studies. Compound 3 catalyzes olefin epoxidation reaction in heterogeneous condition.