3,4-Dimethoxycinnamic Acid is a Cinnamic Acid (C442030) derivative,used in the synthesis of amides and esters through coupling reactions involving carboxylic acids and amines and N-methylation of amides and O-methylation of carboxylic acids.
ChEBI: 3,4-dimethoxycinnamic acid is a methoxycinnamic acid that is trans-cinnamic acid substituted by methoxy groups at positions 3' and 4' respectively. It is functionally related to a trans-cinnamic acid.
GENERAL METHOD: In a dry reaction vessel, veratraldehyde (500 mg, 1.0 eq.) and malonic acid (981 mg, 2.0 eq.) were dissolved in dimethylformamide (5 mL), followed by the addition of DABCO (105 mg, 0.2 eq.). The reaction mixture was stirred at 100-110°C for 60-90 min. The reaction progress was monitored by thin layer chromatography (TLC). After completion of the reaction, the mixture was slowly poured into ice water and extracted with ethyl acetate (3 x 10 mL). The organic phases were combined, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by recrystallization from a chloroform/hexane solvent mixture to afford 3,4-dimethoxycinnamic acid in good yield.
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