Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Sandmeyer reaction is a chemical reaction used to synthesize aryl halides from aryl diazonium salts. It is named after the Swiss chemist Traugott Sandmeyer.An aromatic (or heterocyclic) amine quickly reacts with a nitrite to form an aryl diazonium salt, which decomposes in the presence of copper(I) salts, such as copper(I) chloride, to form the desired aryl halide. The reaction is a radical-nucleophilic aromatic substitution.Several improvements have been made to the standard procedures.