Ethanol → Ethyl 5-fluoropyridine-2-carboxylate

Temperatur

90 °C

A mixture of 2-bromo-5-fluoropyridine (5.00 g, 28.4 mmol), sodium acetate (9.33 g, 114 mmol), and 1-1′bis(diphenylphosphino)ferrocene]dichloropalladium(II):CH2Cl2 (0.464 g, 0.57 mmol) in ethanol (80 mL) in a Parr® high pressure stainless steel reactor vessel is placed under an atmosphere of 50 psi carbon monoxide and heated at 80-100° C. for 4 h. The vessel is cooled, volatiles removed in vacuo, and the residue partitioned between ethyl acetate and water. The ethyl acetate extract is washed with water and brine, dried over sodium sulfate, filtered, and evaporated to give a dark solid. The residue is chromatographed on SiO2 (10% ethyl acetate/hexanes) to yield the title compound 2.8 g (58%) as a white solid that is recrystallized from hexanes to give white crystals: mp 61-63° C.

1. temperatureThe vessel is cooled
2. customvolatiles removed in vacuo
3. customthe residue partitioned between ethyl acetate and water
4. extractionThe ethyl acetate extract
5. washis washed with water and brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. customevaporated
9. customto give a dark solid
10. customThe residue is chromatographed on SiO2 (10% ethyl acetate/hexanes)

ORD-Eintrag

ord-61b52ed67bce44c09e6ab3755fd6da79

Quelldatensatz

uspto-grants-2006_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07087626B2