The employment of N-hydroxy-pyridine-2-carboxamidine in the coordination chemistry of zinc（II）, nickel（II） and manganese（II） under solvothermal conditions is reported. Four complexes of compositions, [Zn2（O2CMe）3{（py）C（NH2）NOH}4]（OH） （1）, [Zn4（OH）2{（py）C（NH2）- NO}4CI2]＇3MeCN （2）, [Ni（SO4）（H20）{（py）C（NH2）NOH}2]＇H2O （3） and [Mn（SO4）{（py）C（NH2）- NOH}2]n （4）, have been synthesized by rationally choosing different metal salts and dexterously employing acetate and sulfate ions as the bridging groups. Luminescent properties for 2 suggested strong emission in the solid state at room temperature. Variable temperature （2.0-300 K） magnetic studies for the linear chain complex 4 indicate weak antiferromagnetic Mn（Ⅱ）...Mn（Ⅱ） exchange interactions.
Five novel SrⅡ-LnⅢ heterometallic coordination polymers based on pyridine-2,6- dicarboxylic acid （H2pda） and imidazole （im）, namely, [LnSr（pda）3（H2O）5]-Him·C2H5OH·3H2O （Ln = Nd （1）; Pr （2））, [Ln2Sr（pda）6（H2O）5]-4Him·C2H5OH·5H2O （Ln = Nd （3）; Pr （4））, and [ErSr（pda）3（H2O）4].Him-3.5H2O （5）, have been prepared and structurally characterized. X-ray crystallographic analyses revealed that these complexes display three varieties of l-D chain structures. Several types of hydrogen bonding interactions are found for 1-5, which connect the 1 -D chain structures to form 2-D suoramolecular networks.
Reaction of 3-（pyridin-2-yl）-imidazo[1,5-a]pyridine （HPIP）, CuCi2·2H20 and picolinaldehyde in the mixture of CHaCOOH and EtOH under solvothermal conditions gave complexes [LCuCI][CuECI3] （1） and [HLCuC1]E[CuCI2]2[CuCI3].2H20 （2） （L = 1,1＇-（pyridin-2- ylmethylene）bis[3-（pyridin-2-yl）imidazo[1,5-a]pyridine]） simultaneously. The ligand L was generated via in situ metal-ligand reaction between HPIP and picolinaldehyde. When CuCI2·2H20 was replaced by CuC1, the 2：1：1（HPIP：picolinaldehyde：CuCI） reaction afforded complex [CuaL2CI2][CuCI2]·2H20 （3） and the analogous 2：1：3 reaction generated compound [CuaL2][CuCI2]3 （4）. Complexes 1 and 2 are Cun/CuI mixed-valence compounds. Complexes 1-4 display four various structures. It is found that the formation of the L ligand is controlled by CH3COOH. This work reveals that the structures of complexes 1-4 could be rationally tuned via the inclusion of CH3COOH in the reaction systems, the proper selection of different starting materials and the dexterous adjustment of the ratio of the starting materials.
Eight new ZnⅡ-yⅢ and ZnⅡ-LnⅢ heterometallic Schiff base complexes： MZnL2（NO3）3 （M = Y （1）, La （2）, Pr （3）, Nd （4）, Eu （5）, Gd （6）, Dy （7）, Er （8）; L = 2-（（（2- （imidazo[1,5-a]pyridin-3-yl）phenyl）imino）methyl）-6-methoxyphenol）, have been rationally synthesized under solvothermal conditions and characterized by IR, elemental analyses （EA）, single-crystal X-ray diffraction, and powder XRD. Furthermore, luminescence in the visible region for solids 1-8 suggested zine/ligand-centered emission at room temperature.
The syntheses, structures and catalytic activities of two yttrium complexes supported by pyrrolide ligands are reported. Treatment of Y（N（Si Me3）2）3 with one equivalent of H3bptd（H3bptd = 1,9-bis（2-pyrrolyl）-2,5,8-triazanona-1,8-diene） in THF gave a complex of composition [Y（bptd）（THF）]2（1）. Reaction of Y（N（Si Me3）2）3 with one equivalent of H3tpa（H3tpa = tris（pyrrolyl-α-methyl）amine） in THF generated [Y（tpa）（THF）3]（2） in good yield. Complexes 1and 2 have been characterized by single-crystal X-ray diffraction, elemental analyses and NMR spectroscopy. Complex 1 is dinuclear. The two metal centers are doubly bridged by two amine nitrogen atoms to form a Y–N–Y–N four-membered rhombus ring. The geometries of Y^3＋ ions in 1and 2 are well described as pentagonal bipyramid and capped octahedron, respectively. The ring-opening polymerization reactions of ε-caprolactone initiated by 1 and 2, respectively, were investigated. They both exhibited good catalytic activity for the polymerization of ε-caprolactone. All of the obtained polymers have high molecular weights and relatively narrower PDIs. The polymers generated by 2 possessed polydispersity close to 1.1. The good catalytic activities of 1 and 2 reveal their potential applications in polymer industry.
