反应详情

3-Furoic acid (5.60 g, 1.0 eq) was dissolved in tert-butanol (200 ml) and treated with triethylamine (10 ml, 1.4 eq) and diphenyl phosphoryl azide (12 ml, 1.1 eq). Mixture was heated at reflux for 18 h. Reaction mixture was cooled to room temperature, then concentrated to 50 ml and poured into saturated aq. NaHCO3. Mixture was stirred at 0° C. for 2 h. Solid was collected by filtration and dried under high vacuum. The crude reaction mixture was purified by flash chromatography to yield tert-butyl furan-3-ylcarbamate 32 (6.95 g, 76%): 1H NMR (CDCl3, 400 MHz) δ 7.71 (bs, 1H), 7.27 (m, 1H), 6.27 (bs, 1H), 6.20 (bs, 1H), 1.50 (s, 9H); MS (Q1) 184 (M)+.

1. temperatureMixture was heated
2. temperatureat reflux for 18 h
3. customReaction mixture
4. concentrationconcentrated to 50 ml
5. additionpoured into saturated aq. NaHCO3
6. filtrationSolid was collected by filtration
7. customdried under high vacuum
8. customThe crude reaction mixture
9. customwas purified by flash chromatography