反应详情

4-Amino-3-pyridinol N,N-diethylcarbamate (4.18 g) was dissolved in CH2Cl2 (75 mL) containing Et3N (2.22 g). The reaction mixture was chilled in an ice-water bath and then acetyl chloride (1.57 g) was added dropwise. After stirring in the cold bath for 15 minutes, the mixture was concentrated under reduced pressure to a volume of ca. 20 mL. This suspension was applied directly to a flash chromatography column and eluted with 5% Et3N/ethyl acetate. The product-containing fractions were concentrated to give 3.76 g of chromatographically pure product. An analytically pure material was obtained by recrystallization from ethyl acetate/pentane, m.p. 102°-104° C.

1. temperatureThe reaction mixture was chilled in an ice-water bath
2. concentrationthe mixture was concentrated under reduced pressure to a volume of ca. 20 mL
3. washeluted with 5% Et3N/ethyl acetate
4. concentrationThe product-containing fractions were concentrated
5. customto give 3.76 g of chromatographically pure product