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

Temperature

-78 °C

Thirty milliliters of a 1.6-M-n-butyllithium hexane solution and a solution of 8.33 g of 4-bromotoluene in 30 ml of tetrahydrofuran were added in this order to 30 ml of tetrahydrofuran which had been cooled to −78° C. in a nitrogen atmosphere, and the mixture was then stirred at −78° C. for 1 hour. A solution containing 6.64 g of zinc chloride which had been dehydrated through heat-melting under reduced pressure in 30 ml of tetrahydrofuran was added thereto at −78° C., and the mixture was stirred at room temperature for 1 hour. This solution was added to a solution of 7.22 g of 2-fluoroiodobenzene and 0.52 g of tetrakis(trifluorophosphine)palladium (0) in 30 ml of tetrahydrofuran at room temperature, and the mixed solution was stirred for 24 hours. The reaction solution was diluted with 300 ml of ethyl acetate, and the dilute solution was extracted with the addition of 10% hydrochloric acid. The organic layer was washed with a saturated aqueous solution of sodium chloride, dried, and then concentrated. The residue was purified through silica-gel column chromatography (eluent: hexane) to give 6.05 g of oily 2-fluoro-4′-methylbiphenyl.

1. additionwas added
2. stirringat −78° C., and the mixture was stirred at room temperature for 1 hour
3. stirringthe mixed solution was stirred for 24 hours
4. extractionthe dilute solution was extracted with the addition of 10% hydrochloric acid
5. washThe organic layer was washed with a saturated aqueous solution of sodium chloride
6. customdried
7. concentrationconcentrated
8. customThe residue was purified through silica-gel column chromatography (eluent: hexane)

ORD record

ord-ad72e24cb4d94b83a216a9bcbe9f96f8

Source dataset

uspto-grants-2002_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06352985B1