Piperonal → Ethyl 5-(2H-1,3-benzodioxol-5-yl)penta-2,4-dienoate

Participants

Reaction Steps

To a solution of 1.85 g (46.3 mmol) of a mineral oil containing 60% sodium hydride in dry tetrahydrofuran (100 ml) was added in an argon atmosphere 10.6 ml (47.8 mmol) of triethyl 4-phosphonocrotonate. The mixture was reacted at 0° C. for 1 hour, followed by addition of 4.86 g (32.3 mmol) of piperonal. The mixture was reacted at room temperature for 1.5 hours. Saturated aqueous solution of ammonium chloride was added to the reaction solution, and the resulting mixture was extracted with ethyl acetate. The organic layer was concentrated under reduced pressure and subjected to silica gel column chromatography. There was obtained 7.23 g (29.6 mmol) of ethyl 5-(3,4-methylenedioxyphenyl)-2,4-pentadienoate. Spectrophotometric data of the product support the structure shown below. ##STR73##

Provenance & Evidence