tert-butyl N-(4-aminobutyl)carbamate → Tert-butyl 4-[(2-chloro-5,6-dimethyl-3-nitropyridin-4-yl)amino]butylcarbamate

Participants

Reaction Steps

A solution of tert-butyl 4-aminobutylcarbamate (8.50 g, 45.2 mmol) in DMF (20 mL) in an addition funnel was added over 1 hour to a stirred solution of 2,4-dichloro-5,6-dimethyl-3-nitropyridine (10.0 g, 45.2 mmol) and triethylamine (9.30 mL, 67.8 mmol) in DMF (100 mL). The addition funnel was rinsed with DMF (17 mL) and the solution was added to the reaction vessel. After the reaction solution was stirred overnight at room temperature, additional tert-butyl 4-aminobutylcarbamate (0.1 equivalent) was added. The solution was allowed to stir an additional 2 hours, then was concentrated under reduced pressure. The resulting oil was partitioned between ethyl acetate (400 mL) and water (100 mL). The organic phase was washed with water (4×50 mL), then was dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by flash chromatography (silica gel, elution with 33% ethyl acetate in hexanes followed by 66% ethyl acetate in hexanes) to afford 9.2 g of tert-butyl 4-[(2-chloro-5,6-dimethyl-3-nitropyridin-4-yl)amino]butylcarbamate.

Provenance & Evidence