Trifluoroacetic anhydride → HCID 73995155, compound

To a stirring solution of 7.61 g (37.8 mmol) of 2-chloro-4-(methoxycarbonyl)-6-methylpyridine 1-oxide in 60 mL of CH2Cl2 was added 24 mL of trifluoroacetic anhydride slowly. The solution was stirred at r.t. for 15.5 h. The temperature was increased to 50° C., and the solution was stirred at 50° C. for 5.5 h and then concentrated. The crude residue was dissolved in 50 mL of THF, and 7% NaHCO3 solution (aqueous) was added to a pH=8. The solution was stirred at r.t. for about 40 h, and EtOAc was added. The aqueous layer was extracted with EtOAc (3×), and the combined extracts were washed with brine (100 mL), dried over Na2SO4, filtered, and concentrated. Purification by flash silica gel chromatography (50% EtOAc/hexanes) provided 4.99 g of methyl 2-chloro-6-(hydroxymethyl)isonicotinate as a pale yellow solid in 66% yield.

1. temperatureThe temperature was increased to 50° C.
2. stirringthe solution was stirred at 50° C. for 5.5 h
3. concentrationconcentrated
4. dissolutionThe crude residue was dissolved in 50 mL of THF
5. addition7% NaHCO3 solution (aqueous) was added to a pH=8
6. stirringThe solution was stirred at r.t. for about 40 h
7. additionEtOAc was added
8. extractionThe aqueous layer was extracted with EtOAc (3×)
9. washthe combined extracts were washed with brine (100 mL)
10. dry with materialdried over Na2SO4
11. filtrationfiltered
12. concentrationconcentrated
13. customPurification by flash silica gel chromatography (50% EtOAc/hexanes)

ORD record

ord-88ea12abe6a048a696f8126035f2556b

Source dataset

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08299267B2