反应详情

To a solution of 2-amino-1-(4-bromophenyl)ethanone hydrochloride salt (1.10 g, 4.39 mmol), (S)-1-(tert-butoxycarbonyl)pyrrolidine-2-carboxylic acid (1.02 g, 4.73 mmol), and diisopropylethylamine (3.10 mL, 17.4 mmol) in DMF (20 mL) was added 3-(diethoxyphosphoryloxy)-(1,2,3)-benzotriazin-4(3H)-one (DEPBT, 2.0 g, 6.68 mmol) and the solution was allowed to stir for 2 hours. The mixture was poured into H2O-ethyl acetate and the layers were separated. The aqueous phase was extracted twice with ethyl acetate and the combined organic layers were washed (H2O×2, brine), dried (Na2SO4), and filtered. The solvent was removed in vacuo and the residue purified by flash column chromatography (1:1 hexanes:ethyl acetate) to provide (S)-tert-butyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)pyrrolidine-1-carboxylate (1.02 g, 56%) as a colorless foam. 1HNMR (400 MHz, DMSO-d6) δ 8.16-8.21 (m, 1H), 7.90-7.92 (m, 2H), 7.73-7.75 (m, 2H), 4.59 (dd, J=5.7, 18.4 Hz, 1H), 4.51 (dd, J=5.7, 18.4 Hz, 1H), 4.13-4.19 (m, 1H), 3.24-3.27 (m, 2H, partially obscured by H2O), 2.05-2.12 (m, 1H), 1.74-1.81 (m, 3H), 1.39 (s, 3H), 1.33 (3, 6H); LCMS: Anal. Calcd. for C18H23BrN2O4: 410. found: 411 (M+H)+.

1. customthe layers were separated
2. extractionThe aqueous phase was extracted twice with ethyl acetate
3. washthe combined organic layers were washed (H2O×2, brine)
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. customThe solvent was removed in vacuo
7. customthe residue purified by flash column chromatography (1:1 hexanes:ethyl acetate)