Iodine → 3-Fluoro-4-iodopyridine-2-carbonitrile

Participants

Reaction Steps

A solution of LDA (40.9 mmol, prepared from 11.4 mL of diisopropyl amine and 16.4 mL of 2.5 M n-butyl lithium in hexanes) in 200 mL THF at −78° C. was treated with 2-cyano-3-fluoropyridine (5.0 g, 40.9 mmol) in 50 mL of THF drop-wise. After 10 minutes a solution of iodine (10.4 g, 40.9 mmol) in 10 mL of TBF was added. After 30 minutes the reaction was quenched with 40 mL of water followed by workup with aqueous sodium thiosulfate. The mixture was diluted with ether, washed with brine, dried over Na2SO4, filtered and concentrated under vacuum. The residue was subjected to silica gel chromatography eluted with 0–20% ethyl acetate in hexanes to provide 3-fluoro-4-iodopyridine-2-carbonitrile that gave proton NMR spectra consistent with theory.

Provenance & Evidence