2,4-Dichlorobenzaldehyde → 6-[3-(2,4-Dichlorobenzylamino)-pyrrolidin-1-yl]-nicotinonitrile

Participants

Reaction Steps

Stir a solution of 6-(3-aminopyrrolidin-1-yl)-nicotinonitrile (200 mg, 1.06 mmol) and 2,4-dichlorobenzaldehyde (371 mg, 2.12 mmol) in methanol (10 mL) for 1 hour. Add 10% sodium borohydride on alumina (400 mg) in one portion and stir for 2 hours. Dilute with dichloromethane (50 mL) and filter through a pad of Celite®. Concentrate to give a residue. Dissolve the residue in 5:95 methanol:dichloromethane and filter through a plug of silica gel. Concentrate to a residue and chromatograph by reverse phase chromatography, eluting with acetonitrile (0.1% trifluoroacetic acid):water (0.1% trifluoroacetic acid). Chromatograph on a SCX column eluting with methanol and then a 1:1 solution of 2.0 M ammonia in methanol:dichloromethane to give the title compound (55 mg, 15%). 1H NMR (400 MHz, CDCl3) δ 8.39 (d, 1H, J=1.8 Hz), 7.57-7.54 (m, 1H), 7.38-7.33 (m, 2H), 7.23-7.20 (m, 1H), 6.32 (d, 1H, J=8.8 Hz), 3.90 (s, 2H), 3.80-3.25 (m, 4H), 2.30-2.19 (m, 1H), 2.05-1.90 (m, 1H), 1.76 (br s, 1H); MS (ES): m/z=347.1, 349.0 [M+H]+.

Provenance & Evidence