P-Anisidine → 7-Methoxy-2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxide

Participants

Reaction Conditions

Reaction Steps

A solution of chlorosulfonyl isocyanate (17 mL, 195 mmol.) was dissolved in 150 mL of nitroethane and cooled to −40° C. A solution of 4-methoxyaniline (Z) (20 g, 162 mmol) in 100 mL of nitroethane was then added drop-wise from a dropper funnel with stirring. After the addition was completed, the reaction was stirred for an additional 5 minutes and aluminum chloride (25 g, 195 mmol) was added. The mixture was then quickly heated to 110° C. with stirring for 20 minutes. The crude material was then poured onto ice and the precipitate was collected by suction filtration, washed with cold water, and dried in vacuo to produce 35 g of the desired product (8) as a purple powder in 95% yield. 1H NMR (400 MHz, DMSO-d6): δ 11.05 (s, 1H), 7.2 (m, 3H), 3.78 (s, 3H), 3.6 (br, 1H).

Provenance & Evidence