Dimethyl Sulfate → 1,3-Dimethoxynaphthalene

To 1,3-Dihydroxynaphthalene (15 g, 93.6 mmol) and potassium carbonate (20 g, 144.7 mmol) in acetone (200 ml) was added dimethyl sulfate (21 ml, 222 mmol). After stirring over-night the reaction mixture was mixed with 10% sodium hydroxide (100 ml) and extracted with ethyl acetate (200 ml×2) The organic layer was washed with water (100 ml×2) evaporated, and the residue stirred with ammonium hydroxide (50 ml) for 2 hrs to quench any unreacted dimethyl sulfate. Product was extracted with ethyl acetate (200 ml) and was washed with water (100 ml×2) and brine (100 ml). The solvent was evaporated yielding 15 g (85%) of 6.