Mechanistic Insights into the FeCl3-Catalyzed Oxidative Cross-Coupling of Phenols with 2-Aminonaphthalenes.

The selective FeCl3-catalyzed oxidative cross-coupling reaction between phenols and primary, secondary, and tertiary 2-aminonaphthalene derivatives was investigated. The generality of this scalable method provides a sustainable alternative for preparing N,O-biaryl compounds that are widely used as ligands and catalysts. Based on a comprehensive kinetic investigation, a catalytic cycle involving a ternary complex that binds to both the coupling partners and the oxidant during the key oxidative coupling step is postulated. Furthermore, the studies showed that the reaction is regulated by off-cycle acid-base and ligand exchange processes.