Trifluoroacetic acid → HCID 66675068, compound

Participants

Reaction Conditions

Reaction Steps

[(S)-1-(5-bromo-1H-imidazol-2-yl)-2-phenyl-ethyl]-carbamic acid tert-butyl ester: To a solution of 92D (30 g) in anisole (100 mL) was added TFA (250 mL) and the reaction was stirred at 100° C. for 18 h. The reaction mixture was evaporated completely, basified with 5% NaOH solution and extracted with DCM. The organic layer was washed with brine, dried over sodium sulfate and concentrated. Recrystallization from hexane gave (S)-1-(5-bromo-1H-imidazol-2-yl)-2-phenyl-ethylamine as a white solid 6 (11 g, 67%). 1HNMR (CD3OD, 400 MHz), δ 7.26 (m, 3H), 7.06 (d, 2H), 6.96 (s, 1H), 4.18 (m, 1H), 3.09 (m, 2H). LCMS m/z 266 (M+H)+. To this intermediate (10 g, 37 mmol) in chloroform (250 mL) was added Boc anhydride (8.6 g, 39 mmol) dropwise at −15° C. over a period of 30 min. The reaction was warmed to 15° C. and stirred at the same temperature for 8 h. The reaction mixture was diluted with chloroform, washed with water and brine, dried over sodium sulfate and concentrated. The crude product was purified by recrystallisation from hexane to give 92E as an off-white solid (12.5 g, 91%). 1HNMR (CDCl3, 400 MHz), δ: 10.2 (bs, 1H), 7.3 (m, 5H), 7.15 (d, 2H), 6.85 (s, 1H), 5.34 (bs, 1H), 4.84 (m, 1H), 3.28 (dd, 2H), 1.38 (s, 9H). LCMS m/z 366 (M+H)+.

Provenance & Evidence