4-Bromotoluene → 2-Fluoro-4'-methyl-1,1'-biphenyl

Participants

Reaction Conditions

Reaction Steps

1.6M-n-Butyllithiumhexane solution (30 ml) is added to tetrahydrofuran (30 ml), the tetrahydrofuran is chilled to −78° C. under a nitrogen environment beforehand. Subsequent to this addition, a tetrahydrofuran (30 ml) solution of 4-bromotoluene (8.33 g) is added. Then, the solution is stirred for one hour at −78° C. A tetrahydrofuran (30 ml) solution of zinc chloride (6.64 g), which had been heat-dissolved and dehydrated under reduced pressure, is added to the solution at −78° C. and the solution is stirred for one hour at room temperature. This solution is added to a tetrahydrofuran (30 ml) solution of 2-fluoroiodobenzene (7.22 g) and tetrakis(triphenylphosphyne)palladium (0.52 g) at room temperature, and the solution is stirred for a day and a night. The reaction solution is diluted with ethyl acetate (300 ml), 10% hydrochloric acid is added, and extraction is performed. After the organic layer is washed with a saturated saline solution and dried, it is concentrated. The residue is purified using silica gel column chromatography (eluate: hexane) and thus, oily 2-fluoro-4′-methylbiphenyl (6.05 g) is obtained. 1H-NMR (CDCl3, δ): 2.39 (3H, s), 7.10-7.30 (5H, m), 7.39-7.49 (3H, m).

Provenance & Evidence