3,5-Dimethylphenol (10 g, 0.082 mol) and anhydrous potassium carbonate (34 g, 0.25 mol) were added to N,N-dimethylformamide (DMF, 150 mL), and methyl iodide (12.8 g, 0.090 mol) was added slowly and dropwise under cooling in an ice bath. The reaction mixture was stirred at room temperature overnight. After completion of the reaction, water was added to the system and extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate and concentrated under reduced pressure. Purification by silica gel column chromatography afforded 3,5-dimethylanisole (10 g, 90% yield).1H NMR (400 MHz, CDCl3) δ: 6.60 (s, 1H), 6.53 (s, 2H), 3.77 (s, 3H), 2.29 (s, 6H).
