5,5,5-trifluoropentanoic Acid → (S)-methyl 2-(5,5,5-trifluoro-N-methylpentanamido)pent-4-enoate
Reaction equation
[F:1][C:2]([F:10])([F:9])[CH2:3][CH2:4][CH2:5][C:6]([OH:8])=O.[CH3:11][NH:12][C@@H:13]([CH2:18][CH:19]=[CH2:20])[C:14]([O:16][CH3:17])=[O:15]>>[F:9][C:2]([F:1])([F:10])[CH2:3][CH2:4][CH2:5][C:6]([N:12]([C@@H:13]([CH2:18][CH:19]=[CH2:20])[C:14]([O:16][CH3:17])=[O:15])[CH3:11])=[O:8]Participants
3
Procedure
Step H (1): 5,5,5-Trifluoropentanoic acid and (S)-methyl 2-(methylamino)pent-4-enoate from Step G (1) were coupled according to the conditions described in Step A (1). The crude reaction products were purified by silica-gel column chromatography to give 191 mg (48% yield) of (S)-methyl 2-(5,5,5-trifluoro-N-methylpentanamido)pent-4-enoate as a clear oil. LC-MS (M+H)+=282.1; 1H NMR (500 MHz, CDCl3) δ ppm 1.86-1.95 (m, 2H) 2.12-2.23 (m, 2H) 2.38-2.50 (m, 3H) 2.70-2.80 (m, 1H) 2.91 (s, 3H) 3.67-3.76 (m, 3H) 5.00-5.17 (m, 2H) 5.27 (dd, J=10.83, 5.04 Hz, 1H) 5.61-5.74 (m, 1H).