Water → 4-Fluoro-2-methylbenzoic acid

A solution of 4-fluoro-2-methyl-benzonitrile (5.0 g, 37 mmol), H2SO4 (20 mL) and H2O (15 mL) was stirred at 80° C. for 17 h. The reaction mixture was cooled to ambient temperature and intermediate carboxamide collected as a precipitate. The material was used without purification. The intermediate carboxamide (5.7 g) was treated with 85% phosphoric acid (20 mL) and stirred at 150° C. for 18 h. After this time, the reaction mixture was cooled to ambient temperature and treated with water (30 mL). The resulting solution was extracted with ethyl acetate (2×200 mL). The combined organic extracts were dried over anhydrous MgSO4, filtered, and concentrated to afford 4-fluoro-2-methyl-benzoic acid. The material was without further purification.

1. customintermediate carboxamide collected as a precipitate
2. customThe material was used without purification
3. additionThe intermediate carboxamide (5.7 g) was treated with 85% phosphoric acid (20 mL)
4. temperatureAfter this time, the reaction mixture was cooled to ambient temperature
5. additiontreated with water (30 mL)
6. extractionThe resulting solution was extracted with ethyl acetate (2×200 mL)
7. dry with materialThe combined organic extracts were dried over anhydrous MgSO4
8. filtrationfiltered
9. concentrationconcentrated

ORD record

ord-8bd974efc9664b56b7b9af7d00f0fe69

Source dataset

uspto-grants-2011_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07968570B2