| The coordination complexes supported by nitrogen-containing heterocyclic ligands have attractedintensive attention of coordination chemists due to their fascinating structures and broad applications asfunctional materials in fluorescence, catalysis, adsorption, and magnetism. Among a varieties ofnitrogen-containing heterocyclic compounds, imidazole, pyridine, pyrazole and pyrrole are favorableligands, owing to their variable structures, good biological activity and strong coordination ability. Inthis thesis, we report the synthesis of coordination complexes based on pyridine derivatives, and theirchemical and physical properties. A number of coordination complexes were prepared bymetal-mediated in situ metal/ligand reactions of3-pyridyl-imidazole[1,5-a] pyridine and differentaldehydes. The plausible mechanisms for these in situ metal/ligand reactions were proposed. In addition,a series of AE-Ln (AE=alkaline earth metal; Ln=lanthanide) heteronuclear complexes andAE-transition metal heteronuclear complexes were synthesized by employing four varieties of pyridinedicarboxylic acids as ligands. And their fluorescence and magnetic properties were studied. Theseresults were briefly described as follows:1. Under solvothermal conditions, a series of reactions of picolinaldehyde, ammonium acetate, andtransition-metal ions were conducted. Five new ligands,pyridin-2-yl(3-(pyridin-2-yl)imidazo[1,5-a]pyridine-1-yl)methanone (L1),1,2-di(pyridin-2-yl)-1,2-bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-1-yl]ethane (L2),1,1’,1’’-(pyridin-2-ylmethanetriyl)-tris{3-(pyridin-2-yl)imidazo[1,5-a]pyridine}(L3),1,1’-(pyridin-2-ylmethylene)bis{3-(pyridin-2-yl)imidazo[1,5-a]pyridine}(L4), and3-(pyridine-2-yl)-1-(pyridin-2-ylmethyl)imidazo[1,5-a]pyridine (L5) and14novel coordinationcomplexes, Fe(L1)Cl2(1), Fe2(L2)Cl4(2), Fe2(L3)Cl4·EtOH (3), Fe(L4)Cl2(4), Co(L1)Cl2·0.5EtOH(5), Co2(L2)Cl4(6), Co2(L3)Cl4·EtOH (7), Co(L5)Cl2(8),[CuI2(L2)Cl2]n(9),[CuII(L3)Cl][CuICl2]·2EtOH (10),[CuIII4(L3)Cl5][Cu2Cl3·2(CuICl2)](11), Cu(L4)Cl·EtOH (12),[L4CuCl]+·[Cu---2Cl3](13),2[HL4CuCl]2+·2(CuCl2)·[CuCl3]2·2H2O (14) were generated via in situmetal-ligand reactions. The structures of these compounds could be controlled rationally via choosingappropriate starting materials and tuning the ratio of the starting materials. The most striking feature ofthe synthesis is that the controllable transformation of the aldehyde group of picolinaldehyde intoketone and secondary, tertiary, and quaternary carbon centers, respectively, has been realized.2. The reactions of CuCl2·2H2O (or CuBr2·2H2O),3-(pyridin-2-yl)imidazo[1,5-a]pyridine (HPIP)and formaldehyde, formic acid, N,N-dimethylformamide (DMF) and glyoxal, respectively, in theabsence/presence of acetic acid under solvothermal conditions were investigated. We found that theCuII-mediated multiple coupling of HPIP and formaldehyde, formic acid, DMF and glyoxal, respectively, where the three bonds of formaldehyde, formic acid, DMF and glyoxal were controllablycleaved, was a very efficient strategy for creating the coordination complexes based on the substitutedimidazo[1,5-a]pyridine. Six novel coordination complexes, namely,[L6Cu2Cl2][Cu2Cl4]·2EtOH (15),[L6Cu2Br2][Cu2Br4]·2EtOH (16),[(L7)2Cu3](CuCl2)3·2EtOH (17),2{[(L7)2Cu3](CuBr2)3}·EtOH (18),L8Cu2Cl2(19) and L8Cu2Br2(20)(L6=tetrakis(3-(pyridin-2-yl)imidazo[1,5-a]pyridin-1-yl)methane,L7=tris(3-(pyridin-2-yl)imidazo[1,5-a]pyridin-1-yl)methane, and L8=1,1,2,2-tetrakis(3-(pyridin-2-yl)-imidazo[1,5-a]pyridin-1-yl)ethane), were generated via in situ metal-ligand reactions. And during thestudy of the mechanism of the in situ meta-ligand reactions, four new complexes, namely,[L6Co2Cl4]·2EtOH (21),[Co2(HPIP)2Cl4](22),[Cu2(HPIP)2Cu2Cl4](23) and L9ZnCl2(24) and onenew ligand L9(bis(3-(pyridin-2-yl)imidazo[1,5-a]-pyridin-1-yl)methane) were generated.3. The reactions of pyridine-2,6-dicarboxylic acid (H2pydc), lanthanide salts and SrCl2·6H2O (orSr(OH)2·8H2O), result in21new complexes, namely,[Sr3(pydc)2(Hpydc)2(H2O)2]n·2nH2O (25)，[Dy3Sr3(pydc)7(Hpydc)(H2O)9]·6H2O (26)，[Ln2Sr3(pydc)6(H2O)18]·nH2O (Ln=Sm (27), Eu (28), n=11; Gd (29), n=16; Tb (30), Dy (31), n=13)，[LnSr(pydc)3(H2O)5]·Him·H2O (Ln=Sm(32), Eu (33),Gd (34), Tb (35), Dy(36))，[Ln2Sr(pydc)6(H2O)5]·4Him·C2H5OH·nH2O (Ln=Sm(37), n=4; Eu (38), n=5; Gd (39), n=4; Dy(40) n=5)，[LnSr(pydc)3(H2O)4]·Him·3H2O (Ln=Gd (41), Tb (42) Dy (43))，[GdSr(pydc)3(H2O)5]·Him·C2H5OH·3H2O (44)and [Sm2Sr2(pydc)5(H2O)9]·2H2O (45), by employingdifferent amount of imidazole (im) in the reaction system. Their fluorescence properties were studied.4. Eight novel SrIIand SrII-transition metal heteronuclear complexes of compositions,[Sr(pydc)(H2O)]n(46),[CuSr(pydc)2(H2O)4]n(47),[CoSr(pydc)2(H2O)6]2n·H2O (48),[NiSr(pydc)2(H2O)4]n·3nH2O (49),[Sr(H2O)6]n·n[Ni(pydc)2(H2O)2]·2nH2O (50),[NiSr2(pydc)3(H2O)8]n·2nH2O (51),[ZnSr(pydc)2(H2O)5]n(52)[ZnSr2(pydc)3(H2O)10]n·2nH2O (53),were afforded by employing pyridine-2,5-dicarboxylic acid as the ligand. The magnetic properties of47，48and51were studied, and the luminescent properties of46，52and53were investigated.5. The employment of pyridine-2,4-dicarboxylic acid (H2pydc) in the construction of SrIIandSrII-MII(M=Co, Ni, Zn and Cu) coordination polymers were reported. Eight complexes ofcompositions,[Sr(pydc)H2O]n(54),[MSr(pydc)2(H2O)2]n(M=Co (55), Ni (56), Zn (57)),[ZnSr(pydc)2(H2O)7]n·4nH2O (58),[SrCu(pydc)2]n(59),[SrCu(pydc)2(H2O)5]n(60) and[Cu3Sr2(pydc)4(Hpydc)2(H2O)2]n(61), have been synthesized. Interestingly, complex59(3-D network)can be reversibly transformed into60(1-D chain) by controlling the temperature of the reaction mixture.The luminescent properties of54and57were measured and the magnetic properties of55,56and61were investigated.6. Five new3D SrII-MII(M=Co, Ni, Zn, Cu) heterometal coordination polymers based onpyridine-2,3-dicarboxylic acid (H2pydc), namely,[MSr(pydc)2(H2O)2]n(M=Co (62), Ni (63)),[MSr2(pydc)3(H2O)4]n·2nH2O (M=Ni (64), Zn (65)),和[CuSr(pydc)2(H2O)3]n·2nH2O (66) have beensynthesized. The magnetic properties of complexes62and63have been investigated. |
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