反应详情

To a 2 liter 4-neck round bottom flask, stirring under a nitrogen atomsphere, was charged 50.0 g (1.0 eq., 0.266 moles) of 6-(3-hydroxyphenyl)-3(2H)-pyridazinone in 500 ml of ethanol followed by 73.4 g of potassium carbonate (2.0 eq., 0.53 moles) and 58.0 g of ethyl bromide (2.0 eq., 0.53 moles) in 50 ml of ethanol. The reaction was stirred at reflux, 70° C.-72° C. for 6 hr. with monitoring by glc. After 6 hr. 5.8 g of ethylbromide was added (0.2 eq., 53 mmoles) and after stirring for an addtional 15 hr. at reflux glc indicated all the starting pyridazinone was consumed. The reaction was worked up by vacuum filtering the mixture while still warm and washing the solid with 2×150 ml of ethanol. The filtrate was concentrated by evaporation under reduced pressure to afford 67.3 g of 6-(3-ethoxyphenyl)-2-ethyl-3(2H)-pyridazinone as a brown oil which solidified.

1. stirringThe reaction was stirred
2. temperatureat reflux, 70° C.-72° C. for 6 hr
3. stirringafter stirring for an addtional 15 hr
4. temperatureat reflux glc
5. customwas consumed
6. filtrationfiltering the mixture
7. temperaturewhile still warm
8. washwashing the solid with 2×150 ml of ethanol
9. concentrationThe filtrate was concentrated by evaporation under reduced pressure