反应详情

Compound of example 2 (15 g, 53.4 mmol) was reacted with acetic anhydride (27.2 g, 269 mmol) in the presence of BF3-etherate (37.9 g, 267 mmol) at 25° C. The reaction mixture was poured over crushed ice, made basic using saturated Na2CO3 solution. It was extracted using CHCl3 (3×200 mL). The organic extract was washed with water, dried (anhydrous Na2SO4), and concentrated. The solid obtained was treated with 5% aqueous NaOH (85 mL) at 55-60° C. for 1 h. It was diluted with ice water (100 mL), acidified with acetic acid (pH 5), and further basified using aqueous Na2CO3 (pH 9). Filtration afforded the compound which was washed with water and dried to get the title compound.

1. additionThe reaction mixture was poured
2. customover crushed ice
3. extractionIt was extracted
4. extractionThe organic extract
5. washwas washed with water
6. dry with materialdried (anhydrous Na2SO4)
7. concentrationconcentrated
8. customThe solid obtained
9. filtrationFiltration
10. customafforded the compound which
11. washwas washed with water
12. customdried