Vilsmeier–Haack reaction
The Vilsmeier–Haack reaction (also called the Vilsmeier reaction) is the chemical reaction of a substituted formamide (1) with phosphorus oxychloride and an electron-rich arene (3) to produce an aryl aldehyde or ketone (5): RC(=O)NR′R″ + HArZ + POCl3 + H2O → RC(=O)ArZ + NR′R″H + HCl + H3PO4 The reaction is named after Anton Vilsmeier and Albrecht Haack. For example, benzanilide and dimethylaniline react with phosphorus oxychloride to produce an unsymmetrical diaryl ketone.