4-Fluoroaniline → Picolinafen

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

6.84 g (25 mmol) of 2-chloro-6-[3-(trifluoromethyl)phenoxy]pyridine (content 99.5 percent, prepared according to Example 1), 3.33 g (30 mmol) of 4-fluoroaniline, 2.92 g (27.5 mmol) of sodium carbonate, 2.8 mg (12.5 μmol) of palladium(II) acetate and 68 mg (125 μmol) of (±)-1-[2-(diphenylphosphino)ferrocenyl]ethyl-di-tert-butylphosphine (IVa, R8=methyl, R9=R10=tert-butyl, R11=R12=phenyl) in 25 ml of acetonitrile were placed in an autoclave at room temperature. The autoclave was flushed with inert gas, carbon monoxide was then introduced under a pressure of 5 bar and the temperature was raised to 150° C., the pressure increasing to 7.6 bar. The mixture was stirred for 4 hours at 150° C. After cooling to room temperature and depressurization, the solvent was distilled off and the residue was taken up at 80° C. with 90 ml of methylcyclohexane. The resultant suspension was filtered and the filter cake was rinsed with 10 ml of warm methylcyclohexane. The product crystallized out when the filtrate was cooled to 5° C. The yield of the title compound was 8.11 g (86.2 percent) of a light beige solid. The melting point of the title compound was 104.5°-105.2° C.

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