3-Cyanopyridine → 3-Cyano-4-iodopyridine

Temperature

-78 °C

To a stirred solution of 2,2,6,6-tetramethyl-piperidine (42.3 g, 0.3 mol) in 2 L of tetrahydrofuran was added butyllithium (120 mL, 2.5 M, 0.3 mol) at −78° C. under N2 atmosphere. The mixture was stirred for 1 hour before a solution of nicotinonitrile (26 g, 0.25 mol) in 500 mL of tetrahydrofuran was slowly added, and the resulting mixture was stirred for 0.5 hour at −78° C. Then I2 (76.2 g, 0.3 mol) in 500 mL of tetrahydrofuran was added in a dropwise manner. After stirring for 2 hours, the mixture was quenched with 500 mL of ice-water. Tetrahydrofuran was removed under reduced pressure and the aqueous phase was extracted with ether. The organic phase was washed with brine, citric acid, brine, aqueous Na2S2O3 and brine again. After being dried over Na2SO4, the organic phase was concentrated and purified by using column chromatography on silica gel (petroleum ether:ethyl acetate, 10:1) to obtain the title compound.

1. additionwas slowly added
2. stirringAfter stirring for 2 hours
3. customthe mixture was quenched with 500 mL of ice-water
4. customTetrahydrofuran was removed under reduced pressure
5. extractionthe aqueous phase was extracted with ether
6. washThe organic phase was washed with brine, citric acid, brine, aqueous Na2S2O3 and brine again
7. dry with materialAfter being dried over Na2SO4
8. concentrationthe organic phase was concentrated
9. custompurified

ORD record

ord-6f594364a82c4dd28db582e3692724b5

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08546377B2