Iodine → 2-Fluoro-3-iodobenzonitrile

Participants

Reaction Conditions

Reaction Steps

n-Butyl lithium (2.5 M in hexanes, 16.8 mL, 42 mmol) was added dropwise to a stirred solution of 2,2,6,6-tetramethylpiperidine (6.90 mL, 141 mmol) in tetrahydrofuran (60 mL) at −78° C. The mixture was stirred for 30 minutes at −50° C. then 2-fluorobenzonitrile (4.4 g, 37 mmol) in tetrahydrofuran (25 mL) was added dropwise to the mixture at −78° C. The reaction was warmed to −50° C. over a 30 minute period and then recooled to −78° C. and a solution of iodine (10.20 g, 40 mmol) in tetrahydrofuran (25 mL) was added. Then the mixture was warmed to ambient temperature. After 1 hour, saturated aqueous sodium thiosulphate solution was added to the reaction and the mixture was extracted with diethyl ether. The organic layer was washed with water, brine, dried (MgSO4) and evaporated. Purification of the residue by flash chromatography (20:1 hexanes/ethyl acetate) gave the title compound (7.86 g, 87%) as a solid.

Provenance & Evidence