Potassium Carbonate → 1-(4,6-Dimethyl-pyridin-2-yl)-4-(3-methyl-4-nitro-phenyl)-piperazine

Participants

Reaction Steps

A solution of 5-chloro-2-nitro-toluene (895 mg, 5.23 mmol) in diglyme (2.5 mL) was added to a stirred suspension of 1-(4,6-dimethyl-pyridin-2-yl)-piperazine (500 mg, 2.62 mmol) and potassium carbonate (900 mg, 6.54 mmol) in diglyme (5 mL) and heated at reflux overnight. The mixture was cooled, the inorganic salts filtered off and washed with ethyl acetate. The filtrate was concentrated to dryness under high vacuum to obtain a residue which was dissolved in 6N hydrochloric acid (10 mL) and washed with toluene. The aqueous layer was basified to pH 8 with ammonium hydroxide solution and extracted with ethyl acetate. The organic layer was washed with water, bicarbonate solution, and brine dried over sodium sulfate, filtered and concentrated to dryness to give the crude compound. Purification by column chromatography over silica gel (60-120 mesh) using 15% ethyl acetate in hexane as a eluent afforded 1-(4,6-dimethyl-pyridin-2-yl)-4-(3-methyl-4-nitro-phenyl)-piperazine (380 mg, 45%).

Provenance & Evidence