Sodium Hydroxide → (E)-5-(3-Methoxyprop-1-enyl)-1H-benzo[c][1,2,6]thiadiazin-4-amine-2,2-dioxide

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Reaction Steps

A solution of (E)-2-sulfamoylamino-6-(3-methoxyprop-1-enyl)benzonitrile (Example 97a) (139 mg, 0.5 mmol) in EtOH was treated with NaOH (2.0 N, 0.5 mL, 1.0 mmol), and the resultant solution was heated to 100° C., and stirred at that temperature for 4 h. After it was cooled down to room temperature, the clear reaction solution was filtered, and the filtrate was carefully neutralized with 10% AcOH while it was vigorously stirred at 0° C. The resultant precipitate was collected by filtration, washed with warm water, and 20% EtOH in water to give the title product (E)-5-(3-Methoxyprop-1-enyl)-1H-benzo[c][1,2,6]thiadiazin-4-amine-2,2-dioxide (108 mg, 78%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ 3.29 (s, 3H), 4.06 (dd, J=4.8, 1.2 Hz, 2H), 6.26 (dt, J=16.2, 5.0 Hz, 1H), 6.91-6.95 (m, 2H), 6.97 (bs, 1H), 7.16 (d, J=7.2 Hz, 1H), 7.46 (t, J=8.0 Hz, 1H), 8.31 (s, 1H), 10.93 (s, 1H). 13C NMR (DMSO-d6) δ 58.4, 72.5, 111.6, 117.0, 122.4, 129.0, 132.5, 134.0, 138.1, 143.7, 162.9. MS 268 (MH+).

Provenance & Evidence