Abstract

The introduction of an aldehyde group into certain aromatic nuclei by means of carbon monoxide, hydrogen chloride, and an appropriate catalyst is know as the Gatterman-Koch reaction. The catalyst commonly used is aluminum chloride with cuprous chloride as a carrier. The carrier is not necessary when high pressure is used. Gatterman discovered the reaction when he tried to extend the Friedel-Crafts reaction to the hypothetical formyl chloride.