Triethylamine → Benzyl 4-((5-chloro-2-pivalamidopyridin-4-ylamino)methyl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A capped microwave reaction vial containing a solution of N-(4,5-dichloropyridin-2-yl)pivalamide (0.38 g, 1.54 mmol) (Synthesis 153-B), benzyl 4-(aminomethyl)piperidine-1-carboxylate (0.76 g, 2 eq) and triethylamine (0.43 mL, 2 eq) in NMP (3 mL) was heated at 210° C. for 1.75 hr under microwave irradiation, and then allowed to cooled. The reaction mixture was diluted with MeOH and adsorbed onto Isolute SCX-II acidic resin (10 g). The resin was washed with methanol, then 2M ammonia in methanol. The basic fractions were concentrated and the crude product was further purified by column chromatography, using a Biotage 40+silica column eluted with a gradient of EtOAc in hexane. The product contained residual NMP which was removed by a second ion exchange purification on Isolute SCX-II acidic resin, eluting with methanol, then 2M ammonia in methanol, to give benzyl 4-((5-chloro-2-pivalamidopyridin-4-ylamino)methyl)piperidine-1-carboxylate as a light yellow gum (0.53 g, 68%).

Provenance & Evidence