反应详情

A solution of ethyl 4,4-dibromo-9-iodo-4,5-dihydrobenzo[b]pyrazolo[1,5-d][1,4]oxazepine-2-carboxylate (0.93 g, 1.71 mmol) in acetone (40 ml) and water (10 ml) was treated with silver(I) nitrate (0.78 g, 4.59 mmol) and then stirred at room temperature for 2 hours. The solids were removed by filtration through celite and carefully washed with acetone (3×50 ml). The filtrate and washings were combined and concentrated in vacuo before the residue was distributed between ethyl acetate (300 ml) and brine (100 ml). The organic layer was separated, dried over MgSO4, filtered and concentrated. The residue was purified by FCC (silica, 0-20% ethyl acetate in heptane) to give 0.54 g (79%) of the title compound as crystalline solid. 1H-NMR (500 MHz, CDCl3) 8 ppm 1.45 (3H, t, J=7.10 Hz), 4.48 (2H, q, J=7.17 Hz), 4.78 (2H, s), 7.06 (1H, d, J=8.39 Hz), 7.67 (1H, s), 7.70 (1H, dd, J=8.54, 2.14 Hz), 8.44 (1H, d, J=2.14 Hz); M+1=399.

1. customThe solids were removed by filtration through celite
2. washcarefully washed with acetone (3×50 ml)
3. concentrationconcentrated in vacuo before the residue
4. customThe organic layer was separated
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was purified by FCC (silica, 0-20% ethyl acetate in heptane)