6299-39-4

95-14-7

6299-39-4

General procedure for the synthesis of 4-nitro-1H-1,2,3-benzotriazole from benzotriazole: Benzotriazole (2 g, 16.8 mmol) was dissolved in concentrated sulfuric acid (70 mL) and the solution was cooled to 0 °C. Potassium nitrate (3.44 g, 34 mmol) was added to the solution in batches over 30 minutes. After the addition was completed, the reaction mixture was heated to 60 °C and maintained at this temperature for 3 hours. Upon completion of the reaction, the mixture was cooled to room temperature and subsequently slowly poured into ice water. The resulting suspension was filtered to collect the precipitate and the precipitate was washed with copious amounts of water until the pH of the wash solution was 7. After drying, 4-nitro-1H-1,2,3-benzotriazole was obtained as a yellow powder in a yield of 2.39 g (87% yield) with a melting point of 218 °C. 1H NMR (400 MHz, DMSO-d6) δ 7.65 (t, 1H), 8.47 (d, 1H) 8.61 (d, 1H).