Br[C:2]1[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][C:3]=1[C:10]([F:13])([F:12])[F:11].CC(N(C)C)=O.[Br-].[CH:21]1([Zn+])[CH2:26][CH2:25][CH2:24][CH2:23][CH2:22]1>C1COCC1>[CH:21]1([C:2]2[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][C:3]=2[C:10]([F:13])([F:12])[F:11])[CH2:26][CH2:25][CH2:24][CH2:23][CH2:22]1A mixture of 4-bromo-3-(trifluoromethyl)benzonitrile (6 g, 24.00 mmol), DMA (30 mL), cuprous iodide (0.914 g, 4.80 mmol) and 1,1′-bis(diphenylphosphino) ferrocenedichloro palladium(II) dichloromethane complex (1.756 g, 2.400 mmol) was bubbled with nitrogen for 5 min. before 0.5 M THF solution of cyclohexylzinc bromide (100 mL, 50.0 mmol) was added over 20 min. via cannula at room temperature. The black reaction mixture was stirred at 60° C. overnight. The reaction mixture was concentrated under reduced pressure. EtOAc (50 mL), water (100 mL) and saturated aqueous ammonium chloride solution (30 mL) were added. The solid was filtered off over a celite pad and washed with ethyl acetate (3×20 mL). The aqueous layer was separated and extracted with ethyl acetate (50 mL). The combined organic solutions were washed with 1 N aqueous HCl (2×40 mL) and then brine (40 mL), dried (sodium sulfate) and concentrated under reduced pressure. Flash chromatography purification (silica gel column, 20→100% ethyl acetate in hexanes) afforded 4-cyclohexyl-3-(trifluoromethyl)benzonitrile (2.77 g, 10.94 mmol, 45.6% yield) as a solid. The compound had an HPLC retention time=3.44 min. (condition C); LC/MS [M+H2O]+1=272.2.
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