Organic carboxylate anions effect on the structures of a series of Mn(II) complexes based on 2-phenylimidazo[4,5-f]1,10-phenanthroline ligand

In our efforts to tune the structures of Mn(II) complexes by selection of organic carboxylic acid ligands, six new complexes [Mn(PIP)2Cl2] (1), [Mn(PIP)2(4,4′-bpdc)(H2O)]·2H2O (2), [Mn(PIP)2(1,4-bdc)] (3), [Mn(PIP)(1,3-bdc)] (4), [Mn(PIP)2(2,6-napdc)]·H2O (5), and [Mn(PIP)(1,4-napdc)]·H2O (6) were obtained, where PIP=2-phenylimidazo[4,5-f]1,10-phenanthroline, 4,4′-H2bpdc=biphenyl-4,4′-dicarboxylic acid, 1,4-H2bdc=benzene-1,4-dicarboxylic acid, 1,3-H2bdc=benzene-1,3-dicarboxylic acid, 2,6-H2napdc=2,6-naphthalenedicarboxylic acid, 1,4-H2napdc=1,4-naphthalenedicarboxylic acid. All complexes have been structurally characterized by IR, elemental analyses, and single crystal X-ray diffraction. Structural analyses show that complexes 1 and 2 possess mononuclear structures, complexes 3, 4, and 5 feature chain structures, and complex 6 exhibits a 2D (4,4) network. The structural difference of 1–6 indicates that organic carboxylate anions play important roles in the formation of such coordination architectures. Furthermore, the thermal properties of complexes 1–6 and the magnetic property of 4 have been investigated.