Iodine → 2-Fluoro-3-iodobenzonitrile

Temperature

-50 °C

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.

1. temperatureThe reaction was warmed to −50° C. over a 30 minute period
2. customrecooled to −78° C.
3. temperatureThen the mixture was warmed to ambient temperature
4. waitAfter 1 hour
5. extractionthe mixture was extracted with diethyl ether
6. washThe organic layer was washed with water, brine
7. dry with materialdried (MgSO4)
8. customevaporated
9. customPurification of the residue by flash chromatography (20:1 hexanes/ethyl acetate)

ORD record

ord-802ddbf0d674417888f189b905af6f4c

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08450341B2