3,4-Diethoxybenzaldehyde is an important organic synthesis intermediate, mainly used in the production of fragrances, dyes, pharmaceuticals, and fluorescent whitening agents.
3,4-dihydroxybenzaldehyde aniline synthesis of 3,4-diethoxybenzaldehyde as an example: in a 50mL three-port round bottom flask, add 15.0mL toluene, 3g aldehyde aniline Schiff base (0.015mol), 5mL (7.3g, 0.067mol) of bromoethane and tert-butanol potassium 1.68g (0.015mol), add magnetic stirrer. Argon protection, reflux and stirring oil bath heating to 80 C, the reaction 12 h. After the reaction, cooling reaction solution, filtration to remove potassium tert-butanol, the solution was added 10 mL of distilled water, 10 mL of ethyl acetate, and fully shaken. The organic phase was separated, and the aqueous phase was extracted with 5mL of ethyl acetate for 3 times, the organic phase was combined and dried with anhydrous sodium sulfate. The organic solvent was removed by rotary evaporation, and the mixed solvent of ethyl acetate and petroleum ether was used as the eluent, by changing the polarity gradient of the solvent, thin-layer plate detection, and column chromatography yielded 1.63g of colorless liquid 3,4-diethoxybenzaldehyde in 72% yield.
