| Schiff base complexes of transition metal ions show high catalytic activity in various reactions. Much attention has been paid to its study and applications. However, those homogenous catalysts are difficult to be separated from reaction system and easy to inactive because of dimerization. The supported metal complexes also showed high catalytic activity and selectivity in comparison to unsupported complexes. The methods immobilizing mental complex involve encapsulating metal complexes into or onto inorganic supports or anchoring the complexes on organic or inorganic supports via formation of a bond between the complex and the supports. In this papers, we have attempted to use monmorillonite as the host materials for immobilization of various schiff base complexes. The reaction was performed under mild conditions using the molecular oxygen as oxidant. The dissertation includes the following contents:Chapter 1: ReviewsIntroduced the synthetic methods of schiff base and the host materials of supported metal complexes, make an overview of the application of in the chemical catalytic reaction (Including oxidation, epoxidation, polymerization ,ring opening polymerization and other reaction).Chapter 2: Synthesis and Catalytic Properties of Montmorillonite-immobilized New Schiff-base complexesA new Schiff base, DAR-PDA were synthesized and characterized by means of FT-IR,1H-NMR and MS. Four mental complexes (Cu, Co, Ni,Mn) were immobilized into montmorillonite by an ion exchange method. Their abilities to catalytic oxidation of cyclohexene with oxygen in the absence of solvent and coreductant were studied. Oxidation reactions occurred inα-C atoms. The product obtained are cyclohexene oxide, 2-cyclohexene-1-ol, 2-cyclohexene-1-one and 2-cyclohexene-1-hydroperoxide. The influences of the amount of catalyst, reaction temperature and the reaction time were investigated. Chapter 3: Oxidation of Cyclohexene with Molecular Oxygen Catalyzed by Binuclear Complexes Immobilized on montmorilloniteFour schiff base mental complexes immobilized into montmorillonite have been prepared. The complexes were characterized by FT-IR, XPS, ICP, TG, SEM and XRD. The catalytic activity of the immobilized complexes was tested in the allylic oxidation of cyclohexene in the absence of solvent with molecular oxygen as oxidant. The results showed that Mn-DAR-OAP-MMT exhibited the best catalytic activity but the Cu-DAR-OAP-MMT had best turnover number. A maximum conversion for oxidation of cyclohexene (63.95%) was observed for Mn-DAR-OAP-MMT/O2 system after 10 h of reaction at 70℃when catalyst amount was 50 mg.Chapter 4: Bridged Schiff-base Complexes immobilized into montmorillonite as catalyst for the oxidation of cyclohexeneA Schiff base was synthesized by the literature and immobilized its four mental complexes (Cu,Co,Ni,Mn) into montmorillonite by an ion exchange method. The Catalytic ability for oxidation of cyclohexene was study. The reaction was performed in the presence of the molecular oxygen in the absence of solvent. The results showed that Mn-DD-ol-S-MMT exhibited the best catalytic activity. The influences of reaction temperature, the amount of catalyst and the reaction time were investigated.Chapter 5: Preparation and Catalysis of Supported New Unsymmetrical Schiff bases Transition Metal Complexes for the Oxidation of CyclohexeneThe new unsymmetrical Schiff base was and characterized by FT-IR, 1HNMR and MS. The four montmorillonite immobilized mental complexes, M-DAR-PDA-S-MMT(M=Cu2+,Co2+,Ni2+,Mn2+) were prepared by an ion exchange method.The catalytic activity was tested in the allylic oxidation of cyclohexene in the absence of solvent with molecular oxygen as oxidant. The product obtained are cyclohexene oxide, 2-cyclohexene-1-ol, 2-cyclohexene-1-one and 2-cyclohexene-1-hydroperoxide. The complexes of Mn-DAR-PDA-S-MMT exhibited the best activity which the cycloxenxne conversion reached to 62.58 % under the temperature of 70℃using 50 mg of catalyst. |
