Methanol → Methyl 3-hydroxy-4-nitrobenzoate

Temperature

0 °C

3-Hydroxy-4-nitro-benzoic acid 1a (3.17 g, 17.32 mmol) was dissolved in 40 mL of anhydrous methanol. The reaction solution was cooled down to 0° C. and added dropwise with thionyl chloride (3.09 g, 25.98 mmol) with stirring. Upon the completion of the addition, the resulting solution was heated to reflux for 2 hours. The reaction solution was concentrated under reduced pressure, extracted with ethyl acetate (200 mL). The combined organic phase was washed with saturated sodium bicarbonate solution (100 mL×3), saturated sodium chloride solution (100 mL×3) successively, then dried over anhydrous magnesium sulfate, filtered and the filtrate was concentrated under reduced pressure to obtain the title compound methyl 3-hydroxy-4-nitro-benzoate 1b (3.30 g as a yellow solid) yield: 96.7%.

1. additionUpon the completion of the addition
2. temperaturethe resulting solution was heated
3. temperatureto reflux for 2 hours
4. concentrationThe reaction solution was concentrated under reduced pressure
5. extractionextracted with ethyl acetate (200 mL)
6. washThe combined organic phase was washed with saturated sodium bicarbonate solution (100 mL×3), saturated sodium chloride solution (100 mL×3) successively
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. concentrationthe filtrate was concentrated under reduced pressure

ORD record

ord-e76abce5915c451b9b78610b819dab94

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08691822B2