反应详情

2-4 (0.73 g, 2.0 mmoles) was added to a 50% aqueous HOAc solution (40 ml) and after stirring at 0°-10° for 10 minutes, Br2 (0.32 g, 2.0 mmoles) was added dropwise. After stirring at 0°-10° for 3 hours, the reaction mixture was diluted with 150 ml H2O and extracted with EtOAc. The organic extract was washed with brine, dried (Na2SO4) and concentrated. The residue was purified by flash chromatography on silica gel eluting with hexane (85)/acetone (15) to give pure 3-1, Rf 0.3.

1. stirringAfter stirring at 0°-10° for 3 hours
2. extractionextracted with EtOAc
3. extractionThe organic extract
4. washwas washed with brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated
7. customThe residue was purified by flash chromatography on silica gel eluting with hexane (85)/acetone (15)
8. customto give pure 3-1, Rf 0.3