Water → 7-Nitro-4-methyl-4H-benzo[1,4]thiazin-3-one

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of 3,4-dihydro-7-nitro-2H-1,4-benzothiazin-3-one (Step 2, 4.7 g, 22.3 mmol) and potassium carbonate (3.70 g, 26.8 mmol) in dry DMF (40 mL) in an ice bath is added iodomethane (4.16 mL, 66.8 mmol). The reaction mixture is taken out of the ice bath and heated at 50° C. for 1–2 h. The resulting mixture is allowed to cool down. Water (35 mL) and ice are added and the precipitate is filtered off and washed with water (10 mL). The resulting solid is dried under high vacuum to give the title compound as a yellow solid (4.5 g, 90%), MS m/z 225.5 (M+H)+.

Provenance & Evidence