125278-10-6Relevant articles and documents
Chemoenzymatic dynamic kinetic resolution of α-trifluoromethylated amines: Influence of substitutions on the reversed stereoselectivity
Cheng, Guilin,Xia, Bo,Wu, Qi,Lin, Xianfu
, p. 9820 - 9828 (2013/09/02)
Enzymatic resolution of α-trifluoromethylated amines via kinetic resolution (KR), dynamic kinetic resolution (DKR) employing CALB-Pd/Al 2O3, and a one-pot sequential process of KR/DKR/KR was investigated comparatively for the first time. Although CALB-catalyzed KR of α-trifluoromethylated amines with substituents of methyl (1a), isopropyl (1c), phenyl (1d) and benzyl group (1e) can provide good stereoselectivity factors E from 31 to >200 respectively, DKR and sequential process of KR/DKR/KR possess better practical application potential because of the higher conversion (62%-84%) and the similar enantiomeric excesses (90%-99%). The enantiopreference and inversion for the α-trifluoromethylated amines displayed by CALB were observed and explained by docking modes. Namely, for 1,1,1-trifluoro-2-propylamine (1a), the product amide with R-configuration was obtained, and the enantiopreference was converted to S for the amines (1b-1e) with substituents larger than methyl group. The catalysts recycle, and scale-up experiments were demonstrated successfully. All these results indicated the high efficiency and green feature of this enzymatic process, and its application significance.
Fungicidal trifluoromethylalkylamino-triazolopyrimidines
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, (2008/06/13)
An improved process for the preparation of (S)-1,1,1-trifluoroalkyl-2-amines of formula IIIA, STR1 where R1 is a C1-6 alkyl group, from the corresponding racemic mixture, which process includes treating 1 part by mole of the racemic mixture with approximately 0.3 to 0.7 part by mole of D-(-)-tartaric acid in the presence of an inert solvent.