Three complexes of tetrachlorophenylporphyrinatomanganese acetates have been synthesized and characterized by IR and UV spectra. The asymmetric epoxdation of styrene has been investigated by using these three complexe...Three complexes of tetrachlorophenylporphyrinatomanganese acetates have been synthesized and characterized by IR and UV spectra. The asymmetric epoxdation of styrene has been investigated by using these three complexes as catalysts, chiral quaternary ammonium salts as phase transfer catalysts, and quinine as chiral auxiliary, sodium hypochlorite as oxidant. The results showed that the structure of manganese porphyrins, the chiral auxiliaries and temperature of reaction affected the asymmetric induction. The best enantiomer excess reached 12 8%.展开更多
The catalysts of nanometer TiO 2/BuOH and hydrous TiO 2 were prepared by the liquid phase method from Ti(SO 4) 2. The properties of the catalysts were characterized by TG DTA, IR, XRD, TEM methods. The results showed ...The catalysts of nanometer TiO 2/BuOH and hydrous TiO 2 were prepared by the liquid phase method from Ti(SO 4) 2. The properties of the catalysts were characterized by TG DTA, IR, XRD, TEM methods. The results showed that nanometer TiO 2/BuOH was anatase particles with 10 nm×20 nm. The main product in styrene epoxidation with t butyl hydroperoxide(TBPH) was styrene epoxide, by product was phenylformaldehyde under the condition of 80 ℃ for 6 h. Hydrous TiO 2 prepared below 260 ℃ was non crystal powder and converted into anatase particles with 10 nm×300 nm when it was roasted at 500 ℃ . The catalytic activity of 10 nm×300 nm anatase particles had only 50% that of particles with 10 nm×20 nm. The centers of acid on the catalyst surface made the epoxide selectivity decrease obviously. The order of the influence of solvent on epoxidation reaction: 1,2 dichloroethane>butanol>cyclohexanone>methyl cyclohexane>cyclohexanol>acetic acid.展开更多
文摘Three complexes of tetrachlorophenylporphyrinatomanganese acetates have been synthesized and characterized by IR and UV spectra. The asymmetric epoxdation of styrene has been investigated by using these three complexes as catalysts, chiral quaternary ammonium salts as phase transfer catalysts, and quinine as chiral auxiliary, sodium hypochlorite as oxidant. The results showed that the structure of manganese porphyrins, the chiral auxiliaries and temperature of reaction affected the asymmetric induction. The best enantiomer excess reached 12 8%.
文摘The catalysts of nanometer TiO 2/BuOH and hydrous TiO 2 were prepared by the liquid phase method from Ti(SO 4) 2. The properties of the catalysts were characterized by TG DTA, IR, XRD, TEM methods. The results showed that nanometer TiO 2/BuOH was anatase particles with 10 nm×20 nm. The main product in styrene epoxidation with t butyl hydroperoxide(TBPH) was styrene epoxide, by product was phenylformaldehyde under the condition of 80 ℃ for 6 h. Hydrous TiO 2 prepared below 260 ℃ was non crystal powder and converted into anatase particles with 10 nm×300 nm when it was roasted at 500 ℃ . The catalytic activity of 10 nm×300 nm anatase particles had only 50% that of particles with 10 nm×20 nm. The centers of acid on the catalyst surface made the epoxide selectivity decrease obviously. The order of the influence of solvent on epoxidation reaction: 1,2 dichloroethane>butanol>cyclohexanone>methyl cyclohexane>cyclohexanol>acetic acid.
