Syntheses, Crystal Structures And Properties Of Amino Acetophenone Schiff Ligands And Their Complexes

The Schiff base compounds, which are prepared by the condensation of aldehyde or ketone with amines or hydrazines, containing the C=N group. The N atom in the C=N group offers the most of metal ion a pair of lone pair electrons. In general, the Schiff base compounds coordinated with metallic ion form mononuclear, multinuclear and hetero-polynuclear coordination compounds. Up to now, researchers in the world have synthesized and charactered kinds of Schiff bases, their metal complexes and exploited uses in many fields. Among them, the multidentate chelating and containing nitrogen and oxygen heteroatoms have the better ligand capability with transition metal atoms, and transition metal complexes of Schiff base have been studied in great details more and more, for their various coordinated feature.In this paper, four Schiff base ligands have been layouted and composited based on 4-aminoacetophenone, O-benzylhydroxylamine and different salicylaldehyde derivatives. The ligands are: 1-(4-{[(E)-5-chloro-2-hydroxybenzylidene]amino}phenyl)ethanone O-benzyloxime(HL1), 1-(4-{[(E)-3,5-dibromo-2-hydroxybenzylidene]amino}phenyl) ethanone O-benzyloxime(HL2), 1-(4-{[(E)-4-methoxy-2-hydroxybenzylidene]amino} phenyl)ethanone O-benzyloxime(HL3), 1-(4-{[(E)-3-bromine-5-chloro-2-hydroxybenzylidene] amino}phenyl)ethanone O-benzyloxime(HL4). A series of transition metal complexes have been designed and synthesized through the reaction of these ligands with Ni(CH3COO)2·4H2O, Co(CH3COO)2·4H2O, Cu(CH3COO)2·H2O, Zn(CH3COO)2·2H2O and Mn(CH3COO)2·4H2O, respectively. In nonaqueous solvents, the single crystals of two ligands and five transition metal complexes have been obtained by means of naturally evaporation of solvents. They are HL1, HL4, [Cu(L1)2](1), [Mn4(L2′)(H2O)2(CH3OH)4](2), Ni(L3)2(3), Cu(L4)2(4), [Mn4(L4′)(H2O)2(CH3OH)4](5), respectively. Simultaneously, these ligands and their complexes have been characterized by physical and chemical methods. The formulas and steric configurations of those complexes have been determined by X-ray crystal single diffraction and their supramolecular structures were discussed at great length. The main crystal data are as following:HL1: Empirical formula, C22H19 Cl N2O2, formula weight, 378.84, Crystal system, Monoclinic, space group: P 2(1)/c, cell parameters: a = 42.678(5) ?, b = 7.2297(9) ?, c = 6.1309(6) ?, β = 91.498(9)°, Z = 1, V = 1891.0(4) ?3, R1 = 0.0292, w R2 = 0.0686;HL4: Empirical formula, C22H18 Br Cl N2O2, formula weight, 457.74, Crystal system, Monoclinic, space group: P-1, cell parameters: a = 9.3658(5) ?, b = 11.2509(7) ?, c = 12.7732(7) ?, β = 76.598(4)°, Z = 1,V = 1243.68(13) ?3, R1 = 0.0608, w R2 = 0.1394;complex 1: Empirical formula, C44H36Cl2 Cu N44, formula weight, 819.21, Crystal system, Triclinic, space group: P-1, cell parameters: a = 11.5270(11) ?, b = 13.7160(12) ?, c = 13.9130(13) ?, α = 63.9930(10)°, β = 87.479(2)°, γ = 84.4170(10)°, Z = 2, V = 1967.6(3) ?3, R1 = 0.0581, w R2 = 0.0944;complex 2: Empirical formula, C38H36Br8Mn4O16, formula weight, 1607.63, Crystal system, Triclinic, space group: P-1, cell parameters: a = 9.3658(5) ?, b = 11.2509(7) ?, c = 12.7732(7) ?, α = 72.341(4)°, β = 76.598(4)°, β = 76.598(4)°, γ = 81.729(4)°, Z = 1,V = 1243.68(13) ?3, R1 = 0.0608, w R2 = 0.1394;complex 3: Empirical formula, C46H42N4 Ni O6, formula weight, 805.53, Crystal system, Monoclinic, space group: P21/c, cell parameters: a = 14.2389(18) ?, b = 6.0122(8) ?, c = 24.677(2) ?, β = 113.353(2)°, Z = 2,V = 1939.5(4) ?3, R1 = 0.0725, w R2 = 0.2141;complex 4: Empirical formula, C44H34Br2Cl2 Cu N4O4, formula weight, 977.01, Crystal system, Monoclinic, space group: C2/c, cell parameters: a = 27.39(3) ?, b = 13.327(15) ?, c = 22.35(3) ?, β = 92.27(2)°, Z = 1, V = 1178.4(2) ?3, R1 = 0.0490, w R2 = 0.1247;complex 5: Empirical formula, C38H36Br4Cl4Mn4O16, formula weight, 1429.83, Crystal system, Triclinic, space group: P-1, cell parameters: a = 9.448(4) ?, b = 11.392(4) ?, c = 12.650(5) ?, α = 72.261(6)°, β = 75.408(6)°, γ = 81.766(6)°, Z = 1, V = 1178.4(2) ?3, R1 = 0.0695, w R2 = 0.1997;...