4,4′-(Pyridine-2,5-diyl)dibenzoic acid as a building block for Cd(II) and Mn(II) coordination compounds: Synthesis, structural features and properties

Abstract

Two new coordination compounds, namely a 3D metal–organic framework (MOF) {[Cd2(L)2(phen)2]·H2O}n (1) and a discrete 0D dimer [Mn(L)0.5(HL)(phen)2]2·2H2O (2), were generated by a hydrothermal method from the metal(II) chlorides, 4,4′-(pyridine-2,5-diyl)dibenzoic acid (H2L) as a main building block, and an ancillary 1,10-phenanthroline (phen) ligand. The products 1 and 2 were characterized by IR spectroscopy, elemental, thermogravimetric, and single-crystal X-ray diffraction analyses. Compound 1 possesses an intricate 3D metal–organic framework based on tetracadmium(II) double-helicate units which, after simplification, resulted in a 4-fold interpenetrated underlying net with the dia topology. Compound 2 features a dimeric molecular structure, which is extended (0D→1D) by hydrogen bonds into a 1D double chain network. It was topologically classified as a simple 3-connected ladder with the SP 1-periodic net (4,4)(0,2) topology. The luminescent (for 1) and magnetic (for 2) properties were also investigated and discussed.