反应详情

温度

-78 °C

A solution of 2,3-dihydro-benzo[1,4]dioxin-6-ylamine (80 g, 530 mmol, 1 eq) in tetrahydrofuran (1000 mL) at −78° C. was treated with concentrated sulfuric acid (50 drops) then N-bromosuccinimide (94.2 g, 530 mmol, 1 eq) was added over 0.5 hour. After the addition the mixture was stirred at −78° C. for 1 hour then treated with solid sodium carbonate (12 g, 113 mmol, 0.21 eq). The mixture was evaporated and the residue partitioned between ether and water. The organic extract was dried, filtered and evaporated to give to oil that was chromatographed on silica gel eluting with dichloromethane to afford oil (141 g, 92%). LC/MS (ES) m/z 230 (MH+ 91%); 1H-NMR (400 MHz, d6-DMSO), 6.85 (1H, s, CHCNH2), 6.34 (1H, s, CHCBr), 4.79 (2H, s, NH2), 4.16 (4H, dd, J=16, 2×(CH2O))

1. additionAfter the addition the mixture
2. customThe mixture was evaporated
3. customthe residue partitioned between ether and water
4. extractionThe organic extract
5. customwas dried
6. filtrationfiltered
7. customevaporated
8. customto give to oil that
9. customwas chromatographed on silica gel eluting with dichloromethane