Synthesis
General procedure for the synthesis of 2-methoxy-6-methylbenzaldehyde from 1-methoxy-2,3-dimethylbenzene: Potassium peroxydisulfate (89.31 g, 0.33 mol) and copper(II) sulfate pentahydrate (27.22 g, 0.11 mol) were added to a mixture of 1-methoxy-2,3-dimethylbenzene (15 g, 0.11 mol) in aqueous acetonitrile ( 750 mL, V/V=1:1). The reaction mixture was stirred under reflux conditions for 15 minutes until complete consumption of the feedstock was confirmed by thin layer chromatography (TLC) detection. Upon completion of the reaction, the mixture was cooled to room temperature and the product was extracted with dichloromethane (2 x 225 mL). The organic layers were combined and washed sequentially with water (2 x 100 mL) and saturated saline (100 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography with the eluent of 4/96 (V/V) ethyl acetate/hexane to afford 2-methoxy-6-methylbenzaldehyde (7.32 g, 44.2% yield). The structure of the product was confirmed by 1H NMR (300 MHz, CDCl3): δ 2.60 (3H, s), 3.90 (3H, s), 6.80 (2H, t), 7.40 (1H, t), 10.65 (1H, s).
References
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