3-Cyanopyridine → 3-Cyano-4-iodopyridine

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence