Acetic Acid → (S)-3-{[4-(3-fluorobenzyloxy)benzyl]methylamino}-pyrrolidin-2-one

Participants

Reaction Steps

One g (0.00318 mol) of (S)-3-[4-(3-fluorobenzyloxy) benzylamino]pyrrolidin-2-one was dissolved in acetonitrile (50 ml) under a nitrogen stream. To this mixture, 1.6 ml (0.0196 mol) of 37% formaldehyde and 0.29 g (0.00460 mol) of sodium cyanoborohydride were added at room temperature. After 20 minutes, glacial acetic acid was dropped up to neutrality of the solution. The mixture was stirred for 40 minutes and was evaporated to dryness. 40 ml of 2 N KOH were added to the residue. After extracting with ethyl acetate, washing with N/2 KOH and then with water and brine, the organic layer was dried on Na2SO4, then filtered and evaporated to obtain a residue which was flash-chromatographed on silica gel (eluant: CHCl3 200: CH3OH 3: 30% NH4OH 0.2) to give 0.73 g (70%) of a white solid.

Provenance & Evidence