反应详情

Ethyl-3-[β-(3-methoxy-4-hydroxyphenyl)ethenyl]-1H-pyrazole-5-carboxylate (0.49 g, 1.7 mmoles) is added to a solution of KOH (0.38 g, 6.8 mmoles) in 50 ml EtOH. The reaction is warmed to reflux overnight. After cooling to room temperature, the reaction is diluted to 200 ml with H2O, and acidified to pH≈4 with HCl. A white precipitate forms, and it is collected by filtration. Drying in vacuum in the presence of P2O5 gives 0.3 g (68%) of the desired product, mp=270°-271° C. (dec).

1. temperatureThe reaction is warmed
2. temperatureto reflux overnight
3. filtrationA white precipitate forms, and it is collected by filtration
4. dry with materialDrying in vacuum in the presence of P2O5