Preparation Process for Piperonal

The following are mixed together under agitation at ambient temperature  

Thus 220 g (1.46 mole) of crude piperonal is isolated which is purified by distillation under reduced pressure. 

Thus 1 78 g (1.186 mole) of pure piperonal is isolated distilling at 106° C. under a vacuum of 2.4 mbars and having a melting point of 37°+l°C. The yield is established at 79% of the theoretically calculated value relative to the 3,4-methylenedioxy mandelic acid used. 

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