23876-18-8

1. Diethyl oxalate (3.9 g, 27 mmol) was dissolved in 30 mL of diethyl ether and added slowly and dropwise to a 6 mL ether suspension of potassium ethanolate (2.3 g, 27 mmol) under stirring. 2. After refluxing had subsided, the reaction mixture was cooled in an ice bath, followed by the slow addition of 3-nitro-o xylene (2.8 g, 18 mmol) dissolved in 3 mL of diethyl ether while maintaining vigorous stirring. 3. The reaction mixture was refluxed for 15 minutes and a thick precipitate was observed to form. 4. The reaction mixture was heated under vacuum to remove most of the ether, followed by the slow addition of 18 mL of 10% sodium hydroxide solution with stirring. 5. hydrogen peroxide (4 mL, 30%) was added slowly and dropwise, during which the reaction was vigorous and accompanied by gas release. 6. Continue stirring the reaction mixture for 1.5 hours. 7. The solid product was collected by vacuum filtration, washed with water and discarded. 8. 8. The filtrate and washings were combined and acidified with 12 N hydrochloric acid to pH 2. 9. 9. The precipitated solid was again collected by vacuum filtration, washed with water and dried under vacuum. 10. The crude product was ground with dichloromethane and further dried under vacuum to give 1.8 g of 2-(2-methyl-6-nitrophenyl)acetic acid in 52% yield.

[1] Patent: US2004/186160, 2004, A1. Location in patent: Page/Page column 22
[2] Patent: US6878733, 2005, B1. Location in patent: Page/Page column 168; 217
[3] Patent: US6350754, 2002, B2. Location in patent: Page column 19-20
[4] Journal of the Chemical Society. Perkin transactions 1, 1969, vol. 14, p. 1935 - 1939