反应详情

Example I was repeated using propionaldehyde diethyl acetal as the azeotropic solvent for the reaction to produce the -alkylidene lactone. For this experiment 100 ml propionaldehyde diethyl acetal was charged to the reactor with 14.9 g (0.10 mole) 3-acetyl-5-methyldihydro-2(3H)-furanone. The mixture was stirred and 4 g (0.10 mole) powdered sodium hydroxyde added. The mixture was allowed to stir for 10 minutes and then heated to reflux for 51/2 hours after which time 14.0 g (0.125 mole) cyclohexanecarboxaldehyde was added over a one-hour period. The mixture was heated under reflux for an additional twelve hours, cooled and worked up to recover 19 g crude 3-cyclohexylmethylene-5-methyldihydro-2(3H)-furanone (59% yield). The structure of the product was confirmed by proton and carbon nuclear magnetic resonance spectroscopy.

1. additionadded
2. stirringto stir for 10 minutes
3. temperatureheated
4. additionwas added over a one-hour period
5. temperatureThe mixture was heated
6. temperatureunder reflux for an additional twelve hours
7. temperaturecooled