Phosphoric Acid → 1-methyl-2-(3-piperidin-4-ylpropyl)-1H-benzimidazole

Participants

Reaction Conditions

Reaction Steps

Phosphoric acid (7 ml) and diphosphorus pentoxide (14 g) were heated at 150° C. for 30 minutes, N-methylbenzene-1,2-diamine (1.3 g) and 4-piperidin-4-ylbutanoic acid hydrochloride (1.5 g) were added thereto, followed by heating at 120° C. for 3 hours. The reaction solution was poured into water, neutralized with aqueous sodium hydroxide solution, and then extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (eluent: chloroform:methanol:aqueous ammonia=10:1:0.1 (v/v/v)) to obtain 1-methyl-2-(3-piperidin-4-ylpropyl)-1H-benzimidazole (1.61 g).

Provenance & Evidence