Dimethylformamide → 5-Bromo-6-(2,2,3,3,3-pentafluoro-propoxy)-pyridine-2-carboxylic acid

Temperature

140 °C

5-Bromo-6-chloro-2-pyridinecarboxylic acid (CAN 959958-25-9; 0.6 g, 2.54 mmol) and potassium tert-butoxide (712 mg, 6.34 mmol) were combined with DMF (30 mL) and THF (10 mL) to give a yellow suspension. To this suspension was added 2,2,3,3,3-pentafluoro-1-propanol (CAN 422-05-9; 3.01 g, 2 ml, 20.1 mmol) and the mixture was heated to 140° C. for 20 hours. After cooling the mixture was poured was poured into ethyl acetate (75 mL) and the combined mixture was washed with cold 1 M HCl (1×10 mL). The aqueous layer was extracted with ethyl acetate (50 mL). The organic layers were combined, dried with Na2SO4 and concentrated in vacuo. The residue was purified by chromatography (silica gel, 20 g, 0% to 100% ethyl acetate in heptane) and further purified by preparative HPLC to give the title compound (0.176 g 20%) as off white solid; MS (EI) 350.1 (M+H)+.

1. customto give a yellow suspension
2. temperatureAfter cooling the mixture
3. additionwas poured
4. washthe combined mixture was washed with cold 1 M HCl (1×10 mL)
5. extractionThe aqueous layer was extracted with ethyl acetate (50 mL)
6. dry with materialdried with Na2SO4
7. concentrationconcentrated in vacuo
8. customThe residue was purified by chromatography (silica gel, 20 g, 0% to 100% ethyl acetate in heptane)
9. customfurther purified by preparative HPLC

ORD record

ord-cd0bf8dfb28348b288f6f2289bf3a5fb

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09321727B2