Acetic Acid → Ammonia

Participants

Reaction Steps

Pyrrolidine (19 μl) was added to a solution of 4-(3-[1-(1H-benzo[d]imidazol-2-ylsulfonyl)-2-piperidyl]-1,2,4-oxadiazol-5-ylmethoxy)benzaldehyde (85 mg) [see Preparation 22] in tetrahydrofuran (10 ml). Sodium triacetoxyborohydride (64 mg) was added followed by glacial acetic acid (11.5 μl). The reaction mixture was stirred under an atmosphere of nitrogen for 6 hours. Sodium triacetoxyborohydride (21 mg) was added and the mixture was stirred for 56 hours after which time the solvent was removed under reduced pressure. The crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 97.5:2.5:0.25 changing to 95:5:0.5, by volume, dichloromethane:methanol:0.88 aqueous ammonia solution to afford 3-[1-(1H-benzo[d]imidazol-2-ylsulfonyl)-2-piperidyl]-5-[4-(1-pyrrolidylmethyl)phenoxy]methyl-1,2,4-oxadiazole (90 mg) as a white solid.

Provenance & Evidence