反应详情

A solution of 18 g of the product from Example 1 in 170 mL of tetrahydrofuran was cooled to 0° C. under an atmosphere of nitrogen and treated with 5 mL of anhydrous ammonia. The mixture was stirred at room temperature for about an hour, filtered to remove the ammonium chloride, and the filtrate concentrated in vacuo to give an off-white solid. This crude product was purified by silica gel chromatography; elution with ethyl acetate-hexanes (3:1) gave 1.9 g of 2-methyl-4-benzothiazolesulfonamide as a white powder, m.p. 236°-239° C.; NMR (DMSO-d6 /CDCl3): δ 2.95 (3H, s), 7.0 (2H, br s, SO2NH2), 7.55 (1H, t, J=8 Hz), 8.0 (1H, dd, J=2, 8 Hz), 8.2 (1H, dd, J=2, 8 Hz).

1. filtrationfiltered
2. customto remove the ammonium chloride
3. concentrationthe filtrate concentrated in vacuo
4. customto give an off-white solid
5. customThis crude product was purified by silica gel chromatography
6. washelution with ethyl acetate-hexanes (3:1)