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Xueqin Zhang,Wencheng Tu,Meitian Xiao,Yongjun Liu,Jing Ye 한국물리학회 2017 Current Applied Physics Vol.17 No.10
A one-step approach was developed to prepare carbon covered alumina (CCA) material by using Al-based MOFs (Al-PCP) as sacrificial template. Pt/CCA nanoparticle catalysts were characterized by using XRD, TGA, XPS, N2 sorption, SEM, TEM and elemental analysis and revealed that they retained the mesostructure with high Pt dispersion and had a CCA structure. Moreover, after reduced at 800 C, Pt/CCA-800 afforded the highest enantiomeric excess (84.8%) after chirally modified with cinchonidine at the second time reaction and can be recycled for more than 8 times without distinct loss of activity or enantioselectivity in the asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate.
Cong Mao,Jie Zhang,Meitian Xiao,Yongjun Liu,Xueqin Zhang 한국물리학회 2018 Current Applied Physics Vol.18 No.12
Mesoporous carbon-silica composites supported Pt nanoparticle catalysts (Pt/MCS) were firstly applied to the heterogeneous asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate (EOPB). A series of different silica contents were investigated in the fabrication of this mesoporous material. When the volume of added tetraethyl orthosilicate (TEOS) during the preparation of composites is 8 mL, Pt/MCS-8 holds carbon and silica as the main components and possesses relatively strong acidity, mesoporous structures with micropores, appropriate Pt nanoparticle size and high dispersibility showing by XRD, XPS, TPD, N2 sorption and TEM. These properties cause its good catalytic performance in the heterogeneous asymmetric hydrogenation of EOPB with the enantiomeric excess value and conversion up to 85.6% and 97.8%, respectively.