Hydrazine → 3-(4-bromo-2-fluorophenyl)-4H-1,2,4-triazole

Participants

Reaction Conditions

Reaction Steps

Hydrazine (0.14 mL, 4.4 mmol) was added to a solution of (E)-4-bromo-N-((dimethylamino)methylene)-2-fluorobenzamide (1.105 g, 4.046 mmol) in acetic acid (11 mL). The resulting white suspension was heated to 95-100° C. The resulting solution was stirred at 95-100° C. for 2 hours. The reaction mixture was cooled to ambient temperature and the acetic acid was azeotropically removed in vacuo with multiple additions of heptane. Heptane (10 mL) was added to the residue. The resulting suspension was cooled to 0-5° C. and stirred for 1 hour. The solids were collected by vacuum filtration, rinsed with excess heptane, and dried to afford 5-(4-bromo-2-fluorophenyl)-1H-1,2,4-triazole (1.116 g, 114%) as an off-white solid which was carried on without further purification.

Provenance & Evidence