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

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.

1. washThe addition funnel was rinsed with DMF (17 mL)
2. additionthe solution was added to the reaction vessel
3. stirringto stir an additional 2 hours
4. concentrationwas concentrated under reduced pressure
5. customThe resulting oil was partitioned between ethyl acetate (400 mL) and water (100 mL)
6. washThe organic phase was washed with water (4×50 mL)
7. dry with materialwas dried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe crude product was purified by flash chromatography (silica gel, elution with 33% ethyl acetate in hexanes followed by 66% ethyl acetate in hexanes)

ORD record

ord-4b9de1c8f1844938b0c3c92e3bc3f42d

Source dataset

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07897767B2