반응 #8207

반응 방정식

ethyl acetate hexane

2-bromo-4,6-difluoro aniline

ethyl chloroformate

→

2-bromo-4,6-difluoro-N-carbethoxy aniline

수율 94.0%

용매

pyridine

반응 조건

후처리

1. 1
   기타the temperature below 5° C
2. 2
   workup.ADDITIONWhen addition
3. 3
   여과filtered
4. 4
   농축the filtrate concentrated
5. 5
   workup.DISSOLUTIONThe residue is dissolved in diethyl ether/ethyl acetate (500 ml/250 ml)
6. 6
   세척washed with H2O, 2.5 N HCl, aqueous NaHCO3, brine
7. 7
   건조dried (Na2SO4)
8. 8
   여과filtered
9. 9
   농축concentrated
10. 10
    기타triturated with petroleum ether

실험 절차

To a vigorously stirred solution of 2-bromo-4,6-difluoro aniline (100 g, 0.48 mol) in pyridine (400 mL), at 0° C., is added ethyl chloroformate (70 ml, 0.73 mol) at a rate to keep the temperature below 5° C. When addition is complete, the mixture is stirred at 0° C.–5° C. an additional 2 hours while monitoring by TLC (20% ethyl acetate/hexane, UV). The reaction is then allowed to warm to room temperature, filtered and the filtrate concentrated. The residue is dissolved in diethyl ether/ethyl acetate (500 ml/250 ml) and washed with H2O, 2.5 N HCl, aqueous NaHCO3, brine, dried (Na2SO4), filtered, concentrated, and triturated with petroleum ether to give 126 g of 2-bromo-4,6-difluoro-N-carbethoxy aniline (94%).

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