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1. To a well-stirred solution of 4-methylsalicylic acid (25 g, 0.164 mol) in dimethyl sulfoxide (75 ml) was added potassium carbonate (68.0 g, 0.492 mol). 2. The reaction mixture was stirred at 35-40 °C and the first batch of ethyl bromide (27.0 g, 0.247 mol) was added slowly over 30 min and stirring was continued for 2 h. The reaction mixture was then stirred for 2 h at the same temperature. 3. Subsequently, a second batch of ethyl bromide (27.0 g, 0.247 mol) was added over 30 min at the same temperature. 4. The reaction mixture was continued to be stirred at 35-40°C for 8 hours. 5. After completion of the reaction, it was cooled to 20-25 °C and diluted with dichloromethane (50 ml). 6. The inorganic salts were removed by filtration and the solid residue was washed with dichloromethane. 7. The filtrate and washings were combined, diluted with water (50 ml) and the organic layer was separated by stirring for 30 minutes. 8. The aqueous layer was further extracted with dichloromethane, all dichloromethane layers were combined and washed with 2 x 50 ml of water. 9. Finally, the solvent was evaporated under reduced pressure to give 34.2 g of ethyl 2-ethoxy-4-methylbenzoate in quantitative yield.

[1] Patent: US6686497, 2004, B1. Location in patent: Page column 3-4
[2] Organic Process Research and Development, 2002, vol. 6, # 2, p. 184 - 186
[3] Patent: WO2016/34673, 2016, A1. Location in patent: Page/Page column 103
[4] Journal of Medicinal Chemistry, 1998, vol. 41, # 26, p. 5219 - 5246