反应详情

To a solution of 2-isocyanato-5-nitro-4-trifluoromethyl-benzoic acid methyl ester (110 mg, 0.379 mmol) in dry THF (1.7 mL) was added a solution of CH3SO2NHNH2 (41.7 mg, 0.379 mmol) in dry THF (0.6 mL) at r.t. The resultant mixture turned into a white suspension that was stirred for one hour. A 1 M aq NaOH solution (0.379 mL) was added and stirring of the clear solution was continued for 4 h. After addition of 2 M HCl solution (0.472 mL) and evaporation of the THF, the precipitate was filtered and dried at 50° C./0.1 mm yielding N-(6-nitro-2,4-dioxo-7-trifluoromethyl-1,4-dihydro-2H-quinazolin-3-yl)-methanesulfonamide (114 mg, 81%) as a slightly yellow powder, m.p. 220-232° C. (decomp.). 1H-NMR (DMSO-d6, 400 MHz): 3.15 (s, 3H), 7.66 (s, 1H), 8.62 (s, 1H), 10.50 (s, 1H), 12.41 (s, 1H).

1. stirringstirring of the clear solution
2. waitwas continued for 4 h
3. filtrationthe precipitate was filtered
4. customdried at 50° C./0.1 mm