73757-44-5

Upstream product

• 18709-45-0 methyl 3-phenyl-2H-azirine-2-carboxylate 

Downstream Products

• 140647-57-0 N-(t)-butyloxycarbonyl-glycyl-DL-3,3-difluoro-phenylalanyl methyl ester 
• 140647-61-6 N-9-fluorenylmethyloxycarbonyl-glycyl-DL-3,3-difluoro-phenylalanyl methyl ester 
• 140647-72-9 cyclo 
• 140647-71-8 cyclo 
• 140647-70-7 cyclo 
• 140647-65-0 N-t-butyloxycarbonyl-L-alanyl-DL-3,3-difluoro-phenylalanyl methyl ester 
• 140647-62-7 N-t-butyloxycarbonyl-L-phenylalanyl-DL-3,3-difluoro-phenylalanine methyl ester 
• 140647-78-5 N-9-fluorenylmethyloxycarbonyl-DL-3,3-difluoro-phenylalanyl methyl ester 

Relevant academic research and scientific papers

Enzymatic hydrolysis of methyl 3,3-difluoro-2-amino esters. Synthesis of D- and L-3,3-difluoro-2-amino acids and their derivatives

The hydrolysis of methyl D,L-3,3-difluorophenyl alanate (1a) and methyl D,L-3,3-difluoro-2-aminobutanoate (1b) and their N-acetyl derivatives 2a and 2b by subtilisin has been studied.All derivatives examined were enzymatically resolved to separable mixtures of the corresponding 3,3-difluoro-L-amino acids (3a and 3b) or N-acetylamino acids (5a and 5b) and the unchanged 3,3-difluoro-D-amino esters (4a and 4b) or N-acetylamino esters (6a and 6b).Acidic hydrolysis of methyl 3,3-difluoro-D-phenyl alanate (4a) or its N-acetyl derivative 6a led to 3,3-difluoro-D-phenyl alanine (8a).In the same manner, L- and D-2-amino-3,3-difluorobutanoic acids 7b and 8b were prepared starting from 5b and 6b.Optical purity and enantiomeric excess were determined by GC analysis of the N-acetyl esters and by NMR analysis determined in the presence of Eu(tfc)3.By these methods, unchanged methyl 3,3-difluoro-D-amino ester derivatives showed an ee of >/= 90percent while L-amino acids were estimated to have >/= 95percent ee. - Keywords: Enzymatic hydrolysis; Methyl difluoroamino esters; Difluoroamino acids; NMR spectroscopy; Subtilisin Carlsburg; Optical activity

New Convenient Synthesis of β,β-Difluoro Amines and β,β-Difluoro-α-amino Acid Alkyl Esters by the Addition of Hydrogen Fluoride to 1-Azirines

The reaction of hydrogen fluoride in pyridine solution with a series of substituted 1-azirines (1) was investigated. β,β-Difluoro amines (4) were obtained in good yields.The exceptions are the cases of 2-phenyl-3-methyl-1-azirine (1b) and 2,3-diphenyl-1-azirine (1c) for which the direct formation of a stabilized carbocation (6) from the azirinium ion 2 is probable.The former gave 54 percent of a pyrazine (11b) and 5 percent of α-fluoropropiophenone (9b) along with 20 percent of difluoro amine 4b, while the latter afforded only the corresponding α-fluoro ketone (9c).A mechanism is suggested.