反应详情

To a solution of tert-butyl 2-(3-bromophenyl)-1-hydroxypropan-2-ylcarbamate (CD1; R4=Me) (1.5 g, 4.6 mmol) in EtOAc (150 mL) at reflux was added IBX (3.82 g, 13.6 mmol, 3 eq). Reflux was continued for another 2 h and then the mixture was cooled to RT. The white precipitate was filtered and the filtrate was concentrated. The residue was purified by chromatography on silica gel by eluting with EtOAc/hexanes to give 1.0 g (66%) of tert-butyl 2-(3-bromophenyl)-1-oxopropan-2-ylcarbamate (CD2; R4=Me) as a colorless oil. 1H NMR (CDCl3) δ 9.42 (s, 1H), 7.69 (m, 1H), 7.60 (m, 1H), 7.55-7.40 (m, 2H), 5.85 (bs, 1H), 1.96 (s, 3H), 1.56 (s, 9H).

1. additionwas added IBX (3.82 g, 13.6 mmol, 3 eq)
2. temperatureReflux
3. filtrationThe white precipitate was filtered
4. concentrationthe filtrate was concentrated
5. customThe residue was purified by chromatography on silica gel
6. washby eluting with EtOAc/hexanes