Methanol → Methyl 2-methyl-4-nitrobenzoate

Temperature

40 °C

To 2-methyl-4-nitrobenzoic acid (10.5 g, 58.0 mmol) in CH2Cl2 (80 ml) was added 2.0 M oxalyl chloride in methylene chloride (39.9 ml, 80 mmol), followed by DMF (0.224 ml, 2.90 mmol). The mixture was stirred at 40° C. for 1.5 h and then at rt for 0.5 h. Solvent was removed and the residue was put on high vacuum for 0.5 h. The acyl chloride prepared was then dissolved in methylene chloride (40 mL) and cooled at 0° C., MeOH (40 mL) was added and the mixture was stirred at 0° C. for 0.5 h. Solvent was removed, the crude was diluted with EtOAc, washed with sat. sodium bicarbonate, brine. The organic layer was dried over sodium sulfate and concentrated to give Intermediate 3A (11.35 g, 58.2 mmol, 100% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ ppm 7.98-8.11 (m, 3H) 3.93 (s, 3H) 2.67 (s, 3H).

1. waitat rt for 0.5 h
2. customSolvent was removed
3. waitthe residue was put on high vacuum for 0.5 h
4. customThe acyl chloride prepared
5. temperaturecooled at 0° C.
6. stirringthe mixture was stirred at 0° C. for 0.5 h
7. customSolvent was removed
8. additionthe crude was diluted with EtOAc
9. washwashed with sat. sodium bicarbonate, brine
10. dry with materialThe organic layer was dried over sodium sulfate
11. concentrationconcentrated

ORD record

ord-472913938d6f419297eceeb05d1c306b

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09174974B2