反应详情

A solution of tert-butyl 4-aminobutylcarbamate (32.12 g, 170.6 mmol) in N,N-dimethylformamide (200 mL) was added over a period of 90 minutes to a solution of 2,4-dichloro-6-methyl-3-nitropyridine (35.09 g, 169.5 mmol) in N,N-dimethylformamide (500 mL). The reaction mixture was stirred at ambient temperature overnight. The solvent was removed by vacuum distillation using a 24/40 short path distillation head and warm water. The residue was dissolved in ethyl acetate (700 mL), washed with water (3×100 mL), dried over magnesium sulfate and then concentrated under reduced pressure. The crude product was purified by column chromatography (50×450 mm silica gel eluting with 1:1 hexane:ethyl acetate) to provide 59.90 g of tert-butyl 4-[(2-chloro-6-methyl-3-nitropyridin-4-yl)amino]butylcarbamate.

1. customThe solvent was removed by vacuum distillation
2. distillationa 24/40 short path distillation head
3. temperaturewarm water
4. dissolutionThe residue was dissolved in ethyl acetate (700 mL)
5. washwashed with water (3×100 mL)
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe crude product was purified by column chromatography (50×450 mm silica gel eluting with 1:1 hexane:ethyl acetate)