esterification. Comparing with previously reported homogeneous and heterogeneous catalysts, Zr‐MOF‐808‐P can promote the reaction for a wide range of primary, secondary and tertiary amides with n‐butanol as nucleophilic agent. Different alcohols have been employed in amide esterification with quantitative yields. Moreover, the catalyst acts as a heterogeneous catalyst and could be reused for at least five
Mapping the substrate selectivity of new hydrolases using colorimetric screening: lipases from Bacillus thermocatenulatus and Ophiostoma piliferum, esterases from Pseudomonas fluorescens and Streptomyces diastatochromogenes
作者:Andrew Man Fai Liu、Neil A Somers、Romas J Kazlauskas、Terry S Brush、Frank Zocher、Markus M Enzelberger、Uwe T Bornscheuer、Geoff P Horsman、Alessandra Mezzetti、Claudia Schmidt-Dannert、Rolf D Schmid
DOI:10.1016/s0957-4166(01)00072-6
日期:2001.3
screened a general library of 29 substrates and a chiral library of 23 pairs of enantiomers. All four hydrolases catalysed the hydrolysis of unnatural substrates, but the two lipases accepted a broader range of substrates than the two esterases. As expected, the two lipases favoured more hydrophobic substrates, while the two esterases showed a preference for smaller substrates. Several moderately enantioselective
Enantioselective transesterification of racemic phenyl ethanol and its derivatives in organic solvent and ionic liquid using Pseudomonas aeruginosa lipase
enantioselectivity (ee) in organic solvents, however, when the catalytic amount of ionic liquids were added in the reaction mixture, excellent enantioselectivity was obtained. Moreover, the change in enantiomer preference was seen in the presence of catalytic amount of ionic liquids. The findings revealed that hydrophobic ionic liquids (two-phase system) were the best solvents and 4-substituted aryl ethanols
thickness were synthesized and used as racemization catalysts in the one‐pot dynamickineticresolution (DKR) of secondary alcohols by using lipase‐catalyzed transesterification. The inert Silicalite‐1 shell covered the external acidic sites of the Beta zeolite core, suppressing dehydration and non‐enantioselective transesterification of the alcohol. The alcohols could penetrate the Silicalite‐1 shell
Two Approaches for CAL-B-Catalyzed Enantioselective Deacylation of a Set of α-Phenyl Ethyl Esters: Organic Solvent with Sodium Carbonate and Micro-aqueous Medium
buffer solution pH 7 in the second. The results show the high efficiency of the deacylation in the presence of the sodium carbonate for the enzymatic resolution of all the esters and that in term of reactivity (31% ≤ conv ≤ 50%) and selectivity (E > 200). While, during the hydrolysis in micro-aqueous media, the conversion is strongly affected by the length of the acyl-chain side, the conversion decreases