2-Chloro-4-nitrobenzoic acid → 2-(Methylthio)-4-nitrobenzoic acid

Temperature

135 °C

A stirred mixture of 2-chloro-4-nitrobenzoic acid (24.2 g, 120 mmol), methyldisulfide (5.6 mL), copper powder (7.6 g) in 160 mL of DMA was heated to 135° C. during 1 hours, kept at that temperature for 90 minutes, and then heated at 165° C. for 2 hours. After the reaction was completed, the solvent was removed in vacuum to afford the crude compound, which was poured into 40% w/v aqueous sodium hydroxide solution. The mixture was filtered and the filtrate was washed with EtOAc and the aqueous layer was acidified with concentrated aqueous hydrochloric acid and filtered. The solid residue was washed with water and then dissolved in EtOAc, and the solution was dried over anhydrous Na2SO4 and evaporated to dryness under reduced pressure. The residue was crystallized from aqueous EtOH to give 2-(methylsulfanyl)-4-nitrobenzoic acid. 1H-NMR (400 MHz, MeOD) δ ppm 8.2˜8.33 (rn, 1H), 8.12˜8.17 (m, 1H), 7.95˜7.98 (m, 1H), 2.53 (s, 3H).

1. temperatureheated at 165° C. for 2 hours
2. customthe solvent was removed in vacuum
3. customto afford the crude compound, which
4. filtrationThe mixture was filtered
5. washthe filtrate was washed with EtOAc
6. filtrationfiltered
7. washThe solid residue was washed with water
8. dissolutiondissolved in EtOAc
9. dry with materialthe solution was dried over anhydrous Na2SO4
10. customevaporated to dryness under reduced pressure
11. customThe residue was crystallized from aqueous EtOH

ORD record

ord-a64fa67dd4304faaad04e779e60653fa

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09056859B2