Hydrochloric Acid → HCID 86652997, compound

Participants

Reaction Steps

To a solution of (2,6-difluorophenyl)-1H-pyrazol-5-amine (2.60 g, 13.3 mmol) in 8 mL of EtOAc and 4 mL of EtOH was added 8 mL of HCl in 2-propanol (5-6 N). The heterogeneous mixture was cooled with an ice-NaCl bath, and isopentyl nitrite (1.83 mL, 13.6 mmol) was added drop wise (within 10 min) to prevent the temperature from exceeding 10° C. After stirring for 15 min, the reaction mixture became homogeneous. Stirring was continued for a total of 40 min. The brown homogeneous solution was diluted with 150 mL of EtOAc, and neutralized with ammonium hydroxide. The EtOAc layer was separated and washed with brine to afford a rusty crystalline solid which was triturated with 15 mL Hexanes. The rusty solid was collected and dried in a vacuum oven at 45° C. for 2 h to afford 1-(2,6-difluorophenyl)-4-nitroso-1H-pyrazol-5-amine This crude material was used without further purification. MS (ES+): 225.1 (M+H)+.

Provenance & Evidence