Carbon Dioxide → HCID 22666419, compound

Temperature

0 °C

In 350 ml of tetrahydrofuran was dissolved 22.9 g of 2,6-difluoroanisole, and to the solution was added dropwise 110 ml of a 1.6 M solution of n-butyllithium in n-hexane at -70° C. over a period of 30 minutes. The resulting mixture was stirred at the same temperature for 1 hour, and carbon dioxide was introduced thereinto, after which the mixture was heated to 0° C. over a period of 1 hour. The reaction mixture was added to a mixed solvent of 300 ml of ethyl acetate and 700 ml of water and the pH was adjusted to 1 with 6N hydrochloric acid, after which the organic layer was separated. The organic layer obtained was washed with a saturated aqueous sodium chloride solution, followed by adding thereto a solution of diazomethane in diethyl ether, and the resulting mixture was stirred at room temperature for 10 minutes and distilled under reduced pressure to remove the solvent. The resulting residue was purified by a column chromatography (eluent; n-hexane:ethyl acetate=10:1) to obtain 16.8 g of methyl 2,4-difluoro-3-methoxybenzoate as colorless crystals.

1. customafter which the organic layer was separated
2. customThe organic layer obtained
3. washwas washed with a saturated aqueous sodium chloride solution
4. additionby adding
5. stirringa solution of diazomethane in diethyl ether, and the resulting mixture was stirred at room temperature for 10 minutes
6. distillationdistilled under reduced pressure
7. customto remove the solvent
8. customThe resulting residue was purified by a column chromatography (eluent; n-hexane:ethyl acetate=10:1)

ORD record

ord-ff1df7aaefce41f5ab5dcbc746b40f4b

Source dataset

uspto-grants-2000_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06025370