Module 5 : Electrophilic Aromatic Substitution

Lecture 13 : Electrophilic Aromatic Substitution - I

5.2.6 Gattermann-Koch Reaction

The formylation of aromatic compound can be accomplished by treatment with CO and HCI in the presence of Lewis acid. The reaction is performed either under pressure or using copper(I) chloride whose role may be to aid the reaction between CO and HCl via the complex which it forms with CO.

Mechanism

In this reaction, presumably the electrophile is the formyl cation A.