Enantioselective liquid–liquid extraction has attracted considerable attention for its potential use in largescale production. Kinetic data are needed for the reliable scale-up of the process. This paper reports the ...Enantioselective liquid–liquid extraction has attracted considerable attention for its potential use in largescale production. Kinetic data are needed for the reliable scale-up of the process. This paper reports the kinetic study of reactive extraction of phenylalanine(Phe) enantiomers with BINAP–copper complex(BINAP–Cu) as a chiral selector. The theory of extraction accompanied by a chemical reaction was applied.The effects of agitation speed, interfacial area, p H value of aqueous phase, initial concentration of Phe enantiomers and initial concentration of BINAP–Cu on the specific rate of extraction were investigated. The forward rate constants of the reactions in the reactive extraction process are 7.93 × 10-5m5/2·mol-1/2·s-1for D-Phe and 1.29 × 10-4m5/2·mol-1/2·s-1for L-Phe.展开更多
The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis...The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis of ibuprofen methyl ester was obtained against an immunogen consisting of tetrahedral phosphonate hapten attached to bovine serum albumin (BSA). The catalytic activity of the catalytic antibody in the water-miscible organic-solvent system composed of a buffer solution and N, N-dimethylformamide (DMF) was studied. With 6% DMF in the buffer solution (containing catalytic antibody 0.25 μmol, 0.2 mol·L-1 phosphate buffer, pH 8) at 37°C for 10 h, a good conversion (48.7%) and high enantiomeric excess (>99%) could be reached. The kinetic analysis of the cata-lytic antibody-catalyzed reaction showed that the hydrolysis in the water-miscible organic-solvent system with DMF in buffer solution followed the Michaelis-Menten kinetics. The catalytic efficiency (Kcat/Km) was enhanced to 151.91 L·mmol-1·min-1, twice as large as that for the buffer solution only.展开更多
Asymmetric hydrogenation of α-keto Weinreb amides has been realized with [Ru（（S）-Sunphos）（benzene）C1]C1 as the catalyst and CeC13·7H20 as the additive. A series of enantiopure -hydroxy Weinreb amides （up ...Asymmetric hydrogenation of α-keto Weinreb amides has been realized with [Ru（（S）-Sunphos）（benzene）C1]C1 as the catalyst and CeC13·7H20 as the additive. A series of enantiopure -hydroxy Weinreb amides （up to 97% ee） have been obtained. Cata- lytic amount of CeC13·7H20 is essential for the high reactivity and enantioselectivity and the ratio of CeC13·7H20 to [Ru（（S）-Sunphos）（benzene）C1]C1 plays an important role in the hydrogenation reaction.展开更多
基金Supported by the National Natural Science Foundation of China(21171054)the Open Fund Project of Key Laboratory in Hunan University(11K029)the Key Laboratory of Hunan Province and Aid program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province
文摘Enantioselective liquid–liquid extraction has attracted considerable attention for its potential use in largescale production. Kinetic data are needed for the reliable scale-up of the process. This paper reports the kinetic study of reactive extraction of phenylalanine(Phe) enantiomers with BINAP–copper complex(BINAP–Cu) as a chiral selector. The theory of extraction accompanied by a chemical reaction was applied.The effects of agitation speed, interfacial area, p H value of aqueous phase, initial concentration of Phe enantiomers and initial concentration of BINAP–Cu on the specific rate of extraction were investigated. The forward rate constants of the reactions in the reactive extraction process are 7.93 × 10-5m5/2·mol-1/2·s-1for D-Phe and 1.29 × 10-4m5/2·mol-1/2·s-1for L-Phe.
基金Supported by the Natural Science Foundation of Zhejiang Province (Y404353)
文摘The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis of ibuprofen methyl ester was obtained against an immunogen consisting of tetrahedral phosphonate hapten attached to bovine serum albumin (BSA). The catalytic activity of the catalytic antibody in the water-miscible organic-solvent system composed of a buffer solution and N, N-dimethylformamide (DMF) was studied. With 6% DMF in the buffer solution (containing catalytic antibody 0.25 μmol, 0.2 mol·L-1 phosphate buffer, pH 8) at 37°C for 10 h, a good conversion (48.7%) and high enantiomeric excess (>99%) could be reached. The kinetic analysis of the cata-lytic antibody-catalyzed reaction showed that the hydrolysis in the water-miscible organic-solvent system with DMF in buffer solution followed the Michaelis-Menten kinetics. The catalytic efficiency (Kcat/Km) was enhanced to 151.91 L·mmol-1·min-1, twice as large as that for the buffer solution only.
文摘Asymmetric hydrogenation of α-keto Weinreb amides has been realized with [Ru（（S）-Sunphos）（benzene）C1]C1 as the catalyst and CeC13·7H20 as the additive. A series of enantiopure -hydroxy Weinreb amides （up to 97% ee） have been obtained. Cata- lytic amount of CeC13·7H20 is essential for the high reactivity and enantioselectivity and the ratio of CeC13·7H20 to [Ru（（S）-Sunphos）（benzene）C1]C1 plays an important role in the hydrogenation reaction.
