4-Hydroxybenzaldehyde → 4-(2-Methoxyethoxy)benzaldehyde

A solution of 5.0 grams (0.041 mole) of 4-hydroxybenzaldehyde, 9.5 grams (0.041 mole) of p-toluene sulfonic acid 2-methoxyethyl ester, and 6.3 grams (0.046 mole) of anhydrous potassium carbonate in 50 mL of dimethylsulfoxide (DMSO) was stirred at ambient temperature for about 72 hours. The reaction mixture was then partitioned between 300 mL of an aqueous mixture of 10% lithium chloride and 100 mL of ethyl acetate. The ethyl acetate portion was washed three times; first, with 100 mL of an aqueous mixture of 10% sodium hydroxide, second, with 100 mL of an aqueous mixture of 10% lithium chloride, and, third, with 100 mL of brine. The resultant organic layer was dried over magnesium sulfate, filtered and concentrated under reduced pressure to a residue. The residue was purified with column chromatography on silica gel using methylene chloride as an eluant. The appropriate fractions were combined and concentrated under reduced pressure, yielding 7.3 grams of the subject compound. The NMR spectrum was consistent with the proposed structure.