Sodium Hydroxide → HCID 66746636, compound

Participants

Reaction Steps

To a suspension of 2-sulfamoylamino-6-propoxybenzonitrile (Example 111a) (4.73 g, 18.53 mmol) in ethanol (65 mL), was added aqueous NaOH (2N, 18.6 ml, 37.06 mmol). The resulting clear solution was refluxed for 3 hours under nitrogen. After cooling to room temperature, the resulting solution was filtered, the filtrate was cooled to 0° C. and neutralized with 10% acetic acid. The resulting precipitate was collected by filtration, suspended in 50 ml of ethanol/water (1:1) and warmed to 40° C. for 20 min. The solid was collected by filtration to provide 4-Amino-5-(propyloxy)-1H-benzo[c][1,2,6]thiadiazine-2,2-dioxide (4 g, 85%) as a pale yellow powder. M.p.: 229-230° C. 1H NMR (400 MHz, DMSO-d6) δ 0.96 (t, J=7.3 Hz, 3H), 1.81 (sext, J=7.3 Hz, 2H), 4.10 (t, J=6.7 Hz, 2H), 6.60 (d, J=8.6 Hz, 1H), 6.73 (d, J=8.6 Hz, 1H), 7.44 (t, J=8.6 Hz, 1H), 7.81 (br s, 1H), 8.35 (br s, 1H), 10.93 (br s, 1H). 13C NMR (400 MHz, DMSO-d6) δ 11.07, 22.18, 71.41, 100.93, 105.64, 110.21, 135.53, 145.16, 158.47, 161.10. MS 256 (MH+).

Provenance & Evidence