[F:1][C:2]1[C:8]([F:9])=[C:7]([F:10])[CH:6]=[C:5]([F:11])[C:3]=1[NH2:4].Br[C:13]1[CH:18]=[CH:17][C:16]([CH3:19])=[CH:15][CH:14]=1.CC(C)([O-])C.[Na+].C(P(C(C)(C)C)C(C)(C)C)(C)(C)C>C1(C)C=CC=CC=1>[F:1][C:2]1[C:8]([F:9])=[C:7]([F:10])[CH:6]=[C:5]([F:11])[C:3]=1[NH:4][C:13]1[CH:18]=[CH:17][C:16]([CH3:19])=[CH:15][CH:14]=1A mixture of 2,3,4,6-tetrafluoroaniline (0.72 g, 4.4 mmol), 4-bromotoluene (0.8 g, 4.7 mmol), toluene (55 ml), sodium tert-butoxide (0.8 g, 8.3 mmol), tri-tert-butylphosphine (130 mg, 0.64 mmol) and bis-dibenzylideneacetone-palladium(0) (125 mg, 0.2 mmol) is heated under nitrogen to 85° C. for 3 h. After cooling, water (50 ml), concentrated aqu. HCl (10 ml) and hyflo (1 g) is added and stirring is continued for about one hour followed by filtration. The organic phase is washed with water twice, evaporated and the residue is subjected to flash chromatography on silica (45 g) using heptane/toluene (2:1) as the eluent to afford N-(2′,3′,4′,6′-Tetrafluorophenyl)-4-methylaniline (0.92 g, 3.6 mmol) as an oil which crystallises (mp. 64-65° C.).
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