反应详情

To a solution of tert-butyl 2-(3-bromophenyl)-1-oxopropan-2-ylcarbamate (CD2; R4=Me) (1.0 g, 3 mmol) in dichloroethane (50 mL) was added methylamine (0.48 g, 6.1 mmol, 2 eq) in water (40%) and 1 mL of AcOH. The solution was allowed to stir at RT for 1 h followed by the addition of sodium triacetoxyborohydride (1.8 g, 8.5 mmol, 2.8 eq). The resulting mixture was stirred at RT for 16 h and quenched with MeOH. After stirring for 30 min the mixture was concentrated in vacuo. The residue was purified by chromatography on silica gel by eluting with EtOAc/MeOH to give 0.62 g (60%) of tert-butyl 2-(3-bromophenyl)-1-(methylamino)propan-2-ylcarbamate (CD3; R1=Me, R4=Me) as a colorless oil. 1H NMR (CDCl3) δ 7.47 (bs, 1H), 7.37 (m, 1H), 7.27 (m, 1H), 7.23 (m, 1H), 5.97 (bs, 1H), 3.18-2.82 (m, 2H), 2.45 (s, 3H), 1.74 (s, 3H), 1.40 (s, 9H). MS (ESI) m/e 342.9 (M+H)+.

1. stirringThe resulting mixture was stirred at RT for 16 h
2. customquenched with MeOH
3. stirringAfter stirring for 30 min the mixture
4. concentrationwas concentrated in vacuo
5. customThe residue was purified by chromatography on silica gel
6. washby eluting with EtOAc/MeOH