反应详情

Concentrated sulfuric acid (0.5 mL) was added slowly at ambient temperature with stirring to 2-methyl-3,5-dinitro-benzoic acid (5.22 g, 23.06 mmol) in anhydrous methanol (200 mL). After refluxing overnight under an argon atmosphere, the reaction was determined to be about 50% complete. Toluene (100 mL) was used to azeotrope the H2O generated from the reaction, and fresh anhydrous methanol (300 mL) and H2SO4 (0.5 mL) were added and the mixture was again refluxed overnight under an argon atmosphere at which point the volatile components were reduced in vacuo. Ethyl acetate and 5% aqueous NaOH were added with stirring, and the product was extracted into the ethyl acetate. The ethyl acetate was then washed twice each with 5% aqueous NaOH and saturated aqueous NaHCO3, once with brine and dried with Na2SO4 to give Intermediate 2(a) (4.65 g, 19.37 mmol) as a white solid in 84% yield.

1. temperatureAfter refluxing overnight under an argon atmosphere
2. additionwere added
3. extractionthe product was extracted into the ethyl acetate
4. washThe ethyl acetate was then washed twice each with 5% aqueous NaOH and saturated aqueous NaHCO3
5. dry with materialonce with brine and dried with Na2SO4