1-Nitropyrazole

Experimental procedure: Toluene (9.2 g, 0.1 mol) and 1-nitropyrazole (1.14 g, 0.01 mol) are dissolved in dichloromethane (50 mL). Into this solution, a solution of triflic acid (0.75 g, 0.01 mol) in dichloromethane (10 mL) is added. The reaction mixture is vigorously stirred at 25 °C under a dry nitrogen atmosphere. After 10 h the reaction mixture is quenched with ice-water and extracted with ether (2 x 50 mL). The ethereal extract is washed with sodium bicarbonate solution (5%, 25 mL) and brine and dried over anhydrous MgSO₄. The ether is evaporated and the residue distilled to yield a mixture of nitrotoluenes (1.16 g, 92%).