Gattermann reaction
The Gattermann reaction , ( also known as the Gattermann formylation and the Gattermann salicylaldehyde synthesis ) is a chemical reaction in which aromatic compounds are formylated by a mixture of hydrogen cyanide ( HCN ) and hydrogen chloride ( HCl ) in the presence of a Lewis acid catalyst such as AlCl3 . 
<triplet> Gattermann reaction <subj> formylated <obj> instance of