반응 #11455

반응 방정식

carbamate

tert-butyl 3-aminopropylcarbamate

2,4-dichloro-5,6-dimethyl-3-nitropyridine

triethylamine

→

tert-butyl 3-[(2-chloro-5,6-dimethyl-3-nitropyridin-4-yl)amino]propylcarbamate

수율 77.2%

용매

N,N-dimethylformamide

N,N-dimethylformamide

반응 조건

후처리

1. 1
   온도was heated to 55° C
2. 2
   온도to cool to ambient temperature overnight
3. 3
   농축concentrated under reduced pressure
4. 4
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate (3 L)
5. 5
   세척Each aliquot was washed with water (2×1 L)
6. 6
   추출they were extracted with ethyl acetate
7. 7
   건조dried over sodium sulfate
8. 8
   농축concentrated under reduced pressure
9. 9
   기타to provide 181 g of crude product
10. 10
    기타This material was recrystallized from acetonitrile

실험 절차

A solution of tert-butyl 3-aminopropylcarbamate (121.39 g, 697 mmol) in N,N-dimethylformamide (200 mL) was slowly added to a solution of 2,4-dichloro-5,6-dimethyl-3-nitropyridine (110 g, 498 mmol) and triethylamine (104 mL, 746 mmol) in N,N-dimethylformamide (900 mL). After stirring at ambient temperature for 20 hours the reaction mixture was heated to 55° C. At 24 hours 0.1 equivalents of the carbamate was added. The reaction mixture was allowed to cool to ambient temperature overnight and then concentrated under reduced pressure. The residue was dissolved in ethyl acetate (3 L). The solution was divided into 3 aliquots (1 L each). Each aliquot was washed with water (2×1 L). The pH of the aqueous washes was adjusted to 10 with potassium carbonate and then they were extracted with ethyl acetate. All of the ethyl acetate layers were combined, dried over sodium sulfate and then concentrated under reduced pressure to provide 181 g of crude product. This material was recrystallized from acetonitrile to provide 138 g of tert-butyl 3-[(2-chloro-5,6-dimethyl-3-nitropyridin-4-yl)amino]propylcarbamate as a yellow solid.

출처