Hydrofluoric Acid → 1-Fluoro-5-methoxy-2-methyl-4-nitrobenzene

Participants

Reaction Conditions

Reaction Steps

Hydrogen fluoride (70%) in pyridine (47.4 ml, 0.48 mol) in a plastic separatory funnel was added dropwise over 20 min. to pyridine (16 mL) in a plastic bottle at −78° C. (dry ice/acetone bath) under nitrogen. Note: reaction was exothermic. After the addition was complete, the reaction was stirred for 10 min. at −78° C. 5-Methoxy-2-methyl-4-nitroaniline (9.11 g, 0.05 mol) was then added and the reaction mixture was stirred for an additional 10 min. at −78° C. Sodium nitrite (5.8 g, 0.08 mol) was then added and the reaction mixture was stirred an additional 10 min. at −78° C. The reaction mixture was allowed to warm to RT and then heated to 60° C. for 2 h. The reaction mixture was then allowed to cool to RT and an ice/water mixture (300 mL) was added. The resultant precipitates were collected by vacuum filtration, washed with water and dried under vacuum. The solid product was recrystallized from methylcyclohexane to give yellow crystals as the title product (5.8 g, 63%).

Provenance & Evidence