Hydrochloric Acid → 6-Chloro-4-(trifluoromethyl)pyridine-2-carboxylic acid

Temperatur

80 °C

To a solution of 300 mg of 2-chloro-6-methyl-4-(trifluoromethyl)-pyridine (1.49 mmol) in pyridine (5 ml) was added a solution of 1.61 g of tetrabutylammonium permanganate (4.46 mmol) in pyridine (4.5 ml) and the reaction mixture was stirred at 80° C. for 3 h. The reaction mixture was then poured into a mixture of water and ice and then NaHSO3 solution (40% in water) was added until the color turned light yellow. The mixture was then acidified by addition of 2N HCl and extracted with ethyl acetate. The combined organic layers were then washed with 1N HCl and brine, dried (Na2SO4), filtered and concentrated. The remaining residue was purified by chromatography (DCM/MeOH 100:0 to 90:10) to yield 224 mg (67%) of a gray liquid. MS (ISP) 224.3 (M−H)−.

1. extractionextracted with ethyl acetate
2. washThe combined organic layers were then washed with 1N HCl and brine
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe remaining residue was purified by chromatography (DCM/MeOH 100:0 to 90:10)

ORD-Eintrag

ord-ad385a6737f54efebaab70ef0ab45955

Quelldatensatz

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07745477B2