Hydrochloric Acid → N-(3,4-dichlorophenyl)-4-(pyrrolidin-3-ylmethyl)piperazine-1-carboxamide

Participants

Reaction Steps

To a stirred solution of tert-butyl 3-[(4-{[(3,4-dichlorophenyl)amino]carbonyl}piperazin-1-yl)carbonyl]pyrrolidine-1-carboxylate (3.39 g, 7.19 mmol) in THF (60 ml) was added a 1M solution of borane in THF (21.6 ml, 21.6 mmol) and the reaction heated to reflux for 4 hours. The cooled reaction mixture was then cautiously quenched by addition of methanol then solvents removed in vacuo to give a white solid. To this was then added saturated HCl in methanol (150 ml) and heated to reflux for 1 hour. The reaction mixture was then evaporated to dryness, partitioned between 2M NaOH and DCM, extracted twice, combined organics dried (Na2SO4), filtered and evaporated to a colorless oil. This was then purified on Isco™ Companion (40 g column: 20% methanolic ammonia/DCM) to give the product N-(3,4-dichlorophenyl)-4-(pyrrolidin-3-ylmethyl)piperazine-1-carboxamide as a white foam (444 mg, 1.24 mmol, 17%).

Provenance & Evidence