| Schiff base compounds have attracted significant attention due to their easy preparation and good coordinative ability.In addition,upon coordinating with metal,the Schiff base ligands can stabilize the metal center and improve the properties of the complexes by adjust the steric and electronic effects of the substituents in ligands.Ni（OAc）2·4H2O and Cu（OAc）2·H2O are environmentally friendly and inexpensive compounds.They can react with organic ligands to form stable complexes that exhibit remarkable catalytic activities.In this research,a series of 8-hydroxyquinolineimine ligands were designed and synthesized.Then the ligands reacted with Ni（OAc）2·4H2O and Cu（OAc）2·H2O,respectively,to give four Ni（II）complexes and four Cu（II）complexes.The catalytic activities of the Ni（II）complexes for the reduction of aldehydes and ketones,and those of the Cu（II）complexes for the oxidation of alcohols,were explored.The main contents of this thesis are outlined below:1.Reactions of Ni（OAc）2·4H2O with（2,6-iPr2C6H3）N=CH（8-C9H5NOH）（HL1）,（2,4,6-（CH3）3C6H2）N=CH（8-C9H5NOH）（HL2）,（4-CH3C6H4）N=CH（8-C9H5NOH）（HL3）,（4-Cl C6H4）N=CH（8-C9H5NOH）（HL4）in refluxing ethanol gave complexes Ni（L1）2（1a）,Ni（L2）2（1b）,Ni（L3）2（1c）,Ni（L4）2（1d）,respectively;Reactions of Cu（OAc）2·H2O with（2,6-iPr2C6H3）N=CH（8-C9H5NOH）（HL1）,（4-Cl C6H4）N=CH（8-C9H5NOH）（HL4）,（4-Br C6H4）N=CH（8-C9H5NOH）（HL5）,（4-OCH3C6H4）N=CH（8-C9H5NOH）（HL6）in refluxing ethanol afforded complexes Cu（L1）2（2a）,Cu（L4）2（2b）,Cu（L5）2（2c）,Cu（L6）2（2d）,respectively.All these complexes were characterized by high-resolution mass spectrometry,infrared spectroscopy and elemental analysis.The structures of complexes 1c,1d,2a and 2d were further determined by X-ray single-crystal diffraction.Complex 1c crystallizes with the space group C2/c,and complex 1d crystallizes with the space group P1?.Both of them are mononuclear dual-ligand Ni（II）complexes.The geometry of the nickel atom in 1a and 1d can be best described as a distorted octahedral geometry environment.The central copper atom in mononuclear dual-ligand Cu（II）complex 2a is situated in a slightly distorted square planar geometry.Each layer of the trinuclear layered Cu（II）complex 2d has the similar structure to2a.Two Cu（II）complexes are also crystallized in a triclinic crystal system with the space group P1?.2.The catalytic activities of complexes 1a-1d in the reduction of aldehydes and ketones were explored by using Ph Si H3 as a reductant.The possible mechanism of the reduction was investigated.Among the four Ni（II）complexes,1c shows the highest catalytic activity.This catalyst system has good substrate compatibility.3.The catalytic activities of complexes 2a-2d in the oxidation of alcohols were explored by using TEMPO as the co-catalyst.The possible mechanism of oxidation was studied.Among the four Cu（II）complexes,2a is the most active one.This catalyst system can oxidize the primary and secondary aromatic alcohols to the corresponding aromatic aldehydes and ketones.However,this catalytic system does not work in the oxidation of both primary and secondary aliphatic alcohols. |
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