methyl 3,5-dihydroxynaphthalene-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3,5-dihydroxy-2-naphthoic acid (5.05 g) in MeOH (100 mL) was added TsOH (93 mg). Tho reaction mixture was stirred at reflux for 18 hours and then CH(OMe)3 (1 mL) was added. The reaction mixture was stirred at reflux for an additional 5 hours, at which point H2SO4 (10 drops) was added. After an additional 18 h, the reaction mixture was cooled to rt, poured into saturated aqueous NaHCO3 and extracted with EtOAc. The extract was dried over MgSO4 and concentrated in vacuo to give the title compound as a yellow-white solid (5.19 g, 96%). Tho reaction mixture at reflux for 18 hours The reaction mixture was stirred was added extracted with EtOAc The extract was dried over MgSO4 concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Methyl 3,5-dihydroxy-2-naphthoate (3.27 g; 15 mmole) was mixed with potassium carbonate (3 g; 22 mmole), acetone (50 μL) was added and then dimethylsulfate (Merck) (1.56 mL; 16.5 mmole) was slowly added drop by drop. The reaction mixture was refluxed for 2 hours, cooled to room temperature and water (100 mL) was added thereto, whereat all potassium carbonate was dissolved. Dichloromethane (100 mL) was added to the solution and the layers were separated. The organic layer was dried over anhydrous sodium sulfate and the solvent was evaporated to dryness. The solid residue was recrystallized from methanol and 2.4 g (70%) of methyl 3-hydroxy-5-methoxy-2-naphthoate were obtained. was added The reaction mixture was refluxed for 2 hours the layers were separated The organic layer was dried over anhydrous sodium sulfate the solvent was evaporated to dryness The solid residue was recrystallized from methanol