Explanation of Stephen reaction mechanism with example

Stephen reaction is used to synthesise aldehydes from nitriles. In this reaction, the nitrile compound is first converted to an iminium salt in presence of catalyst tin (II) chloride.This is simply the reduction of CN group to CHNH2+Cl- (iminium salt). The iminium salt formed as an intermediate undergoes hydrolysis reaction to form an aldehyde.The following equation suggests the chemical reaction involved.

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