Hydrochloric Acid → 1-(2-Difluoromethoxy-4-nitro-phenyl)-4-isopropyl-piperazine

Participants

Reaction Conditions

Reaction Steps

1-Bromo-2-difluoromethoxy-4-nitro-benzene (Step A, 2.0 g, 7.5 mmol, 1.0 eq.) and N-(2-propyl)piperazine (0.85 mL, 9.7 mmol, 1.3 eq.) were dissolved in 20 mL of DMSO. K2CO3 (1.5 g, 11.2 mmol, 1.5 eq.) and Bu4N+Br− (240 mg, 0.75 mmol, 0.1 eq.) were added and the mixture was heated to 120° C. The mixture was stirred for 3 h and cooled to RT, poured into H2O (200 mL) and 6 N HCl (20 mL). The aqueous solution was washed with EtOAc, and alkalinized with 6 N NaOH then extracted with EtOAc. The combined organic layers were dried (MgSO4), filtered and concentrated. The crude material was further purified by column chromatography (0-100% EtOAc in hexanes) providing pure 1-(2-difluoromethoxy-4-nitro-phenyl)-4-isopropyl-piperazine.

Provenance & Evidence