Nitric Acid → 5-Chloro-2-methyl-3-nitrobenzoic acid

Temperature

-5 °C

A solution of 5-chloro-2-methylbenzoic acid (9.9 g, 58 mmol) in concentrated H2SO4 (70 ml, 1310 mmol) was cooled to −5° C. in an acetone/ice bath. A mixture of concentrated nitric acid (4.9 ml, 75 mmol) and concentrated H2SO4 (5.0 ml, 94 mmol) was added dropwise to the reaction mixture at −5° C. over 30 minutes. The reaction mixture was stirred at −5° C. for 2 hours before being poured onto ice (150 g) and the precipitate collected by filtration. The precipitate was dissolved in EtOAc (100 ml) and washed with brine (100 ml) before being dried over MgSO4, filtered and concentrated under reduced pressure to give 11.9 g of the title compound as an off-white solid. This material was used without further purification. LC-MS 57%, m/z=214.0/216.0, 1H NMR (500 MHz, Chloroform-d) δ 10.37 (1H, br. s.), 8.19 (1H, d, J=2.21 Hz), 7.91 (1H, d, J=2.21 Hz), 2.67 (2H, s).

1. additionwas added dropwise to the reaction mixture at −5° C. over 30 minutes
2. additionbefore being poured onto ice (150 g)
3. filtrationthe precipitate collected by filtration
4. dissolutionThe precipitate was dissolved in EtOAc (100 ml)
5. washwashed with brine (100 ml)
6. dry with materialbefore being dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure

ORD record

ord-188ce56e78c04ba3bd782df2e37c8740

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376422B2