106942-32-9

Upstream product

• 101468-97-7 N-benzoyl-(4'-nitro)phenylalanine 
• 1991-83-9 4-nitrophenylalanine 
• 98-88-4 benzoyl chloride 
• 69935-12-2 (S)-4-nitro-N-benzoyl-phenylalanine 
• 949-99-5 4-nitro-3-phenyl-L-alanine 

Downstream Products

• 106746-00-3 N-[3,3,3-Trifluoro-2-oxo-(4-nitrophenylmethyl)propyl]benzamide 
• 106943-05-9 N-[1-(4-Amino-benzyl)-3,3,3-trifluoro-2-oxo-propyl]-benzamide; hydrochloride 
• 106942-39-6 4-(4-Nitro-benzyl)-2-phenyl-4-(2,2,2-trifluoro-acetyl)-4H-oxazol-5-one 
• 109004-93-5 2,2-Difluoro-pent-4-enoic acid 4-(4-nitro-benzyl)-2-phenyl-oxazol-5-yl ester 

Relevant academic research and scientific papers

Peptide-catalyzed conversion of racemic oxazol-5(4 H)-ones into enantiomerically enriched α-amino acid derivatives

We report the development and optimization of a tetrapeptide that catalyzes the methanolytic dynamic kinetic resolution of oxazol-5(4H)-ones (azlactones) with high levels of enantioinduction. Oxazolones possessing benzylic-type substituents were found to perform better than others, providing methyl ester products in 88:12 to 98:2 er. The mechanism of this peptide-catalyzed process was investigated through truncation studies and competition experiments. High-field NOESY analysis was performed to elucidate the solution-phase structure of the peptide, and we present a plausible model for catalysis.

Ring opening with kinetic resolution of azlactones by Ti-TADDOLates

The kinetic resolution of azlactones by the Lewis, acid-mediated transfer of an isopropoxide ligand from the chiral ligand sphere of Ti- TADDOLate is described. The reactions proceed with in-situ racemization of the starting material to afford highly enantiomerically enriched N-benzoyl- amino acid isopropylesters (er > 95:5 after recrystallization). The absolute configuration of the major enantiomer of N-benzoyl-phenylalanine isopropyl ester and its analogs with other aromatic substituents was shown to be (S)- (+) when the (R,R)-Ti-TADDOLate was employed. Only benzyl-substituted azlactones can be opened enantioselectively by the method described here.

SYNTHESIS OF FLUORINATED α-AMINO KETONES PART I: α-BENZAMIDOALKYL MONO- DI- AND TRIFLUOROMETHYL KETONES

2-Phenyl-5(4H)-oxazolones, obtained from α-amino acids, are reacted with di- and trifluoro acetic anhydride by a modified Dakin-West procedure to yield in a one-pot reaction α-benzamidoalkyl-di- and trifluoromethyl ketones in good yields.The monofluoromethyl analogues were also prepared from α-amino acids, however the use of the highly toxic fluoroacetic anhydride was avoided.The key step is the halogen exchange reaction on the corresponding bromomethyl ketone.