Abstract: Phase transfer catalysed alkylation has been successfully applied to the synthesis of the intermediate 4-diisopropylamino-2-(2-pyridyl) butanonitrile (Ⅲ), and the conditions of the reaction for synthesizing the intermediate 2-(2-pyridyl) phenyacetonitrile have been improved.The final product is consequently of a better quality and a higher yield; and thetechnique used is less expensive.