100992-58-3Relevant academic research and scientific papers
Enzymatic racemization of amines catalyzed by enantiocomplementary ω-Transaminases
Koszelewski, Dominik,Grischek, Barbara,Glueck, Silvia M.,Kroutil, Wolfgang,Faber, Kurt
, p. 378 - 383 (2011)
A strategy for the biocatalytic racemization of primary α-chiral amines was developed by employing a pair of stereocomplementary PLP-dependent ω-transaminases. The interconversion of amine enantiomers proceeded through reversible transamination by a prochiral ketone intermediate, either catalyzed by a pair of stereocomplementary ω-transaminases or by a single enzyme possessing low stereoselectivity. To tune the system, the type and concentration of a nonchiral amino acceptor proved to be crucial. Finally, racemization could be achieved by the cross-transamination of two different amines without a requirement for an external amino acceptor. Several synthetically and industrially important amines could be enzymatically racemized under mild reaction conditions. ω-Transaminases play ping-pong: A biocatalytic protocol for the 'clean' racemization of α-chiral prim-amines was developed by an equilibrium-controlled deamination/amination sequence catalyzed by a pair of (R)- and (S)-ω-transaminases (see scheme).
Optical activity 1-cyclohexyl ethylamine preparation method
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, (2016/10/08)
The present invention discloses an optical activity 1-cyclohexyl ethylamine preparation method, which comprises that: in water and under the effect of HBr, N-acetylamino-1-cyclohexyl ethylamine represented by a formula 4 or 4' is subjected to a hydrolysis reaction to correspondingly prepare the optical activity 1-cyclohexyl ethylamine represented by a formula 5 or 5'. The preparation method of the present invention can further comprise that a compound represented by a formula I is subjected to an oximation reaction, a reduction acylation reaction and an asymmetric catalysis reaction to prepare the N-acetylamino-1-cyclohexyl ethylamine represented by the formula 4 or 4'. According to the present invention, the preparation method has characteristics of simple operation, low production cost, high product chemical purity, high product optical purity, high product yield, and green environmental protection. The formulas such as 4, 4', 5 and 5' are defined in the specification.
Organocatalytic Kinetic Resolution of Sulfoximines
Dong, Shunxi,Frings, Marcus,Cheng, Hanchao,Wen, Jian,Zhang, Duo,Raabe, Gerhard,Bolm, Carsten
supporting information, p. 2166 - 2169 (2016/03/05)
An efficient kinetic resolution of sulfoximines with enals was realized using chiral N-heterocyclic carbene (NHC) catalysts. The stereoselective amidation proceeds without additional acyl transfer agent. Both enantiomers of the sulfoximines can be obtaine
Nanomole-scale assignment of configuration for primary amines using a kinetic resolution strategy
Miller, Shawn M.,Samame, Renzo A.,Rychnovsky, Scott D.
supporting information, p. 20318 - 20321 (2013/02/23)
The absolute configurations of primary amines were assigned using a kinetic resolution strategy with Mioskowski's enantioselective 1-(R,R) and 2-(S,S) acylating agents. A simple mnemonic was developed to determine the configuration. A pseudoenantiomeric pair of reagents, 1-(R,R) and 2-(S,S)-d 3, was prepared and used to assay primary amines on a micromolar scale. The ESI-MS readout of the resulting acetamide products reproduced the selectivity factors from kinetic experiments. The method can be used on mixtures of amines and was validated with amine samples as small as 50 nmol.
Stereoselective Aldol Reaction with Chiral Secondary Acetamides
Devant, Ralf,Braun, Manfred
, p. 2191 - 2207 (2007/10/02)
The deprotonated acetamides 4a - c and 5a - c are added to prochiral carbonyl compounds.The influence of the solvent, of the reaction temperature, and of the enolate gegenion on the ratio of the isomeric products 8/9, 18/19, and 26/27, respectively, are studied.The highest degree of diastereoselectivity are observed, when the titanium enolate of the acetamide 4a or the threefold deprotonated N-acetyl-α-phenylglycinol (5a) is used.The diastereomers 18a - d, formed in excess in the addition of 5a to aldehydes, are isolated in pure from by a single recrystallization, and afford the enantiomerically pure β-hydroxy carboxylic acids 3a - d.Thereby, the chiral auxiliary, α-phenylglycinol (14), is recovered.
