Piperidine → 5-Nitro-2-(piperidin-1-yl)benzonitrile

Participants

Reaction Steps

2-Chloro-5-nitrobenzonitrile (20 g) and piperidine (9.34 g) were added to acetonitrile (100 ml) and the mixture was stirred at the refluxing temperature for 1 hr. The solvent was evaporated under reduced pressure. Diisopropyl ether was added to the residue to allow crystallization and the crystals were recrystallized from methanol to give 5-nitro-2-piperidinobenzonitrile (17 g). Subsequently, ammonium chloride (1.6 g) and iron powder (8.4 g) were added to a mixed solvent of water (40 ml) and ethanol (120 ml) and the mixture was heated to 65° C. 5-Nitro-2-piperidinobenzonitrile (10 g) was added by portions over 20 min and the mixture was stirred at the refluxing temperature for 30 min. The reaction mixture was ice-cooled and the reaction solution was filtrated. The solvent was evaporated under reduced pressure. An aqueous sodium hydroxide solution was added and the mixture was extracted with toluene. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. Diisopropyl ether was added to the residue to allow crystallization and the crystals were recrystallized from a mixed solvent of ethyl acetate-n-hexane to give the title compound (8.3 g). melting point: 148-149° C.

Provenance & Evidence