[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]#N)=[CH:4][C:3]=1[CH3:11].[CH3:12]I.[H-].[Na+].O.C[N:18]([CH:20]=O)C>>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([CH3:12])([CH3:9])[C:20]#[N:18])=[CH:4][C:3]=1[CH3:11]To a stirred solution of 2-(4-bromo-3-methylphenyl)acetonitrile (11.2 g, 53.3 mmol) in anhydrous DMF (125 mL) is added methyl iodide (13.2 mL, 213 mmol). The solution is cooled to 0° C. and sodium hydride (60% susp. in oil, 3.84 g, 160 mmol) is added in small portions over 20 min. The reaction mixture is then left stirring and slowly warmed up to room temperature for 18 h. At 0° C., water (500 mL) is then slowly added then extracted with ethyl acetate containing 10% of hexanes. The organic layer is separated, dried with MgSO4, filtered and concentrated under reduced pressure to provide the expected product 2-(4-bromo-3-methylphenyl)-2-methylpropanenitrile (12.6 g, 99%) as a clear yellow oil which is used in the next step without further purification. 1H NMR (400 MHz, CHLOROFORM-D) δ ppm 1.71 (s, 6H) 2.43 (s, 3H) 7.14 (dd, J=8.40, 2.34 Hz, 1H) 7.34 (d, J=2.54 Hz, 1H) 7.53 (d, J=8.40 Hz, 1H)
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