反应详情

A mixture of acetic anhydride (11.13 ml) and formic acid (5.93 ml) was stirred at ambient temperature for 30 minutes. To this solution was added 5-amino-1-(2-hydroxyethyl)pyrazole (5 g) under ice-cooling, and the mixture was stirred at 30°-40° C. for 1 hour. The reaction mixture was poured into a mixture of water, tetrahydrofuran and ethyl acetate and adjusted to pH 6 with aqueous sodium bicarbonate. The organic layer was separated, and the aqueous layer was extracted with a mixture of tetrahydrofuran and ethyl acetate for three times. The organic layers were combined, dried over magnesium sulfate and evaporated in vacuo to give 5-formamido-1-(2-formyloxyethyl)pyrazole (5.18 g).

1. temperaturecooling
2. stirringthe mixture was stirred at 30°-40° C. for 1 hour
3. customThe organic layer was separated
4. extractionthe aqueous layer was extracted with a mixture of tetrahydrofuran and ethyl acetate for three times
5. dry with materialdried over magnesium sulfate
6. customevaporated in vacuo