The efficient catalytic systems generated in situ from RuCl2（PPh3）3 and chiral ligands N,N-bis[2-（di-o-tolylphosphino）-benzyl]cyclohexane-1,2-diamine（2） were employed for asymmetric transfer hydrogenation of aro...The efficient catalytic systems generated in situ from RuCl2（PPh3）3 and chiral ligands N,N-bis[2-（di-o-tolylphosphino）-benzyl]cyclohexane-1,2-diamine（2） were employed for asymmetric transfer hydrogenation of aromatic ketones, giving the corresponding optically active alcohols with high activities（up to 99% conversion） and excellent enantioselectivities（up to 96% e.e.） under mild conditions. The chiral ruthenium（Ⅱ） complex （R,R）-3 has been prepared and characterized by NMR and X-ray crystallography.展开更多
The kinetics of the hydrolysis of p-nitrophenyl picolinate(PNPP) catalyzed by zinc complex of schiff base macrocyclic polyamine(Zn2+ complex of 1,4,7,10,13,16-hexaazacyclooctadeca-1,3,10,12-tetraene was abbreviated to...The kinetics of the hydrolysis of p-nitrophenyl picolinate(PNPP) catalyzed by zinc complex of schiff base macrocyclic polyamine(Zn2+ complex of 1,4,7,10,13,16-hexaazacyclooctadeca-1,3,10,12-tetraene was abbreviated to ZnL2+)were studied at 25℃and pH=7.00.The pseudo-first-order rate constant(kψ)of the catalytic PNPP hydrolysis was 8.85×10-3 s-1,which was 463 times larger than that of the spontaneous hydrolysis of PNPP at pH=7.00.The effect of surfactants(Brij35,CTAB,and SDS),pH,temperature,and the concentration of ZnL2+ on the PNPP hydrolysis catalyzed by ZnL2+ was also studied in present paper.The thermodynamic and kinetic parameters of the titled reaction were obtained with the mathematical model.The activated water molecule in the reactant-catalyst complex was a strongly nucleophilic species,which could promote the PNNP hydrolysis reaction effectively.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.2042300220703034)+1 种基金the Natural Science Foundation of Fujian Province of China(No.2008J0235)the Natural Science Foundation of Guangxi Province of China(No. 0991016)
文摘The efficient catalytic systems generated in situ from RuCl2（PPh3）3 and chiral ligands N,N-bis[2-（di-o-tolylphosphino）-benzyl]cyclohexane-1,2-diamine（2） were employed for asymmetric transfer hydrogenation of aromatic ketones, giving the corresponding optically active alcohols with high activities（up to 99% conversion） and excellent enantioselectivities（up to 96% e.e.） under mild conditions. The chiral ruthenium（Ⅱ） complex （R,R）-3 has been prepared and characterized by NMR and X-ray crystallography.
文摘The kinetics of the hydrolysis of p-nitrophenyl picolinate(PNPP) catalyzed by zinc complex of schiff base macrocyclic polyamine(Zn2+ complex of 1,4,7,10,13,16-hexaazacyclooctadeca-1,3,10,12-tetraene was abbreviated to ZnL2+)were studied at 25℃and pH=7.00.The pseudo-first-order rate constant(kψ)of the catalytic PNPP hydrolysis was 8.85×10-3 s-1,which was 463 times larger than that of the spontaneous hydrolysis of PNPP at pH=7.00.The effect of surfactants(Brij35,CTAB,and SDS),pH,temperature,and the concentration of ZnL2+ on the PNPP hydrolysis catalyzed by ZnL2+ was also studied in present paper.The thermodynamic and kinetic parameters of the titled reaction were obtained with the mathematical model.The activated water molecule in the reactant-catalyst complex was a strongly nucleophilic species,which could promote the PNNP hydrolysis reaction effectively.
