Cesium carbonate → tert-Butyl (2-chloro-5-fluoropyridin-4-yl)carbamate

Temperatur

100 °C

tert-Butyl carbamate (960 mg), cesium carbonate (5.06 g), Pd2(dba)3 (1.07 g), and Xantphos (1.35 g) were added to a toluene solution (40 ml) containing 2-chloro-5-fluoro-4-iodopyridine (2 g), followed by stirring at 100° C. for 3 hours. The reaction solution was adjusted to room temperature and water was added to the reaction solution, followed by extraction with ethyl acetate. The organic layers were washed with saturated saline and dried over anhydrous sodium sulfate. The solvent was distilled away under reduced pressure and the obtained residue was purified by silica gel chromatography (n-hexane:ethyl acetate=9:1 to 4:1). A yellow oily matter of tert-butyl (2-chloro-5-fluoropyridin-4-yl)carbamate (1.53 g) was thus obtained.

1. customwas adjusted to room temperature
2. extractionfollowed by extraction with ethyl acetate
3. washThe organic layers were washed with saturated saline
4. dry with materialdried over anhydrous sodium sulfate
5. distillationThe solvent was distilled away under reduced pressure
6. customthe obtained residue was purified by silica gel chromatography (n-hexane:ethyl acetate=9:1 to 4:1)

ORD-Eintrag

ord-03c91063e62a4b90ac9c3ff8a207582d

Quelldatensatz

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09051310B2