Duff Reaction and Mechanism

Formylation of phenols at ortho position using hexamethylenetetramine (HMTA) in acidic conditions is called Duff reaction. If ortho positions are blocked, then formylation occurs at the para position. The Duff reaction is also known as hexamine aromatic formylation.

Mechanism of Duff Reaction

The Mechanism is related to that for the Reimer–Tiemann reaction, which uses chloroform as the formylating agent. Mechanism begins with the protonation of hexamine ring to open and generate an iminium group followed by the addition to the aromatic ring and complete in the following steps-

Duff Reaction Examples