Benzo[c]isothiazol-7-amine synthesis

Yield:1379298-69-7 19%

Reaction Conditions:

with sodium sulfide in ethanol;water at 60; for 0.75 h;

Steps:

44

7-Nitro-1, 2-benzisothiazole (SYIITLIESIS, 1978,58 ; EP 454621 ; 250 mg, 1.39 mmol) and sodium sulfide nonahydrate (867 mg, 3.61 mmol) in 1: 1 ethanol-water (10 ml) were stirred and heated at 60°C for 45 minutes. The mixture was then cooled to room temperature and diluted with ethyl acetate. The organic phase was washed with water then brine, dried over sodium sulfate, filtered and concentrated to dryness. The crude product was purified by column chromatography on silica gel eluting with 50: 1 DCM- MEOH to give a pale brown solid (40 mg, 19%). 1H NMR (CDC13, 400 MHz) 8 8. 88 (1H, s), 7.53 (1H, d, J7. 8), 7.30 (1H, T, J7. 7), 6.78 (1H, D, J7. 4), 3.97 (2H, s).

References:

WO2005/28445,2005,A2 Location in patent:Page/Page column 42