Synthesis
2-(4-Bromophenyl)-3-methylbutanenitrile was synthesized as follows: to a solution of 4-bromophenylacetonitrile (20.0 g, 0.102 mol) in DMF (300 mL) was slowly added NaH (60% oil suspension, 4.28 g, 0.107 mol) at 0 °C. After addition, the mixture was continued to be stirred for 15 min, followed by the addition of 2-bromopropane (9.60 mL, 0.107 mol). The reaction mixture was gradually warmed to room temperature and stirred continuously for 2 hours. Upon completion of the reaction, the mixture was concentrated under vacuum. The residue was extracted by partitioning between dichloromethane (CH2Cl2) and brine. The organic phases were combined, dried with anhydrous sodium sulfate (Na2SO4), filtered and concentrated in vacuum. Finally, the residue was purified by fast column chromatography (silica gel, gradient elution with heptane solution of 0-15% ethyl acetate) to afford the target product 2-(4-bromophenyl)-3-methylbutanenitrile (21.3 g). Mass spectral analysis showed m/z 238.3, 240.2 [M/M+2H]+.
References
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