2-Furancarboxylic acid → 5-Acetylfuran-2-carboxylic acid

Temperature

-78 °C

To a solution of diisopropylamine (27.5 mL, 0.20 mol) in 200 mL of THF at 0° C. was added n-butyllithium (78.5 mL, 0.196 mol; 2.5M in hexanes). The solution was stirred 30 min and was cooled to -78° C. A solution of furoic acid (10.0 g, 0.089 mol) in 100 mL of THF was added and the solution stirred 30 min. To this mixture was added N-methoxy- N-methyl-acetamide (13.8 g, 0.134 mol) in 50 mL of THF. The reaction mixture was warmed to room temperature and stirred 1 h. The mixture was quenched with saturated ammonium chloride solution and the aqueous layer was washed with ether (3×50 mL) to remove impurities. The aqueous layer was acidified with 2M HCl and extracted with ethyl acetate (3×100 mL). The combined organic extract was washed with brine, dried over MgSO4, filtered and evaporated to yield 11.1 g (81%) of 2-acetyl-fur-5-yl carboxylic acid.

1. stirringthe solution stirred 30 min
2. temperatureThe reaction mixture was warmed to room temperature
3. stirringstirred 1 h
4. customThe mixture was quenched with saturated ammonium chloride solution
5. washthe aqueous layer was washed with ether (3×50 mL)
6. customto remove impurities
7. extractionextracted with ethyl acetate (3×100 mL)
8. extractionThe combined organic extract
9. washwas washed with brine
10. dry with materialdried over MgSO4
11. filtrationfiltered
12. customevaporated

ORD record

ord-bf5b3602c234402684a1e8738d6628a5

Source dataset

uspto-grants-1992_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05112848