Trifluoroacetic acid → Fotagliptin

Beteiligte Stoffe

Reaktionsschritte

To a solution of (R)-tert-butyl 1-(4-(2-cyano-5-fluorobenzyl)-6-methyl-5-oxo-4,5-dihydro-1,2,4-triazin-3-yl)piperidin-3-ylcarbamate (20, 37 mg) in dichloromethane (1 mL) was added TFA (0.5 mL) and the mixture was stirred at RT for 1 h. The mixture was carefully neutralized with NaHCO3 (aq, saturated), and extracted with CH2Cl2 (10 mL×3). The combined extracts were dried over Na2SO4 and concentrated to give the crude product, which was purified by column chromatography on silica gel, and eluted with 92:6:2 dichloromethane-methanol-ammonia to provide (R)-2-((3-(3-aminopiperidin-1-yl)-6-methyl-5-oxo-1,2,4-triazin-4(5H)-yl)methyl)-4-fluorobenzonitrile (21). 1H NMR (400 MHz, DMSO, ppm): δ 7.96 (m, 1H), 7.36 (br, 1H), 7.29 (d, 1H), 5.23 (s, 2H), 3.15 (m, 3H), 2.72 (m, 2H), 2.23 (s, 3H), 1.78 (d, 1H), 1.64 (d, 1H), 1.47 (m, 1H), 1.12 (m, 1H). MS: m/z, 343 (100%, M+1);

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