Heterogeneously Catalyzed Selective Acceptorless Dehydrogenative Aromatization to Primary Anilines from Ammonia via Concerted Catalysis and Adsorption Control.

Although catalytic dehydrogenative aromatization from cyclohexanones and NH 3 is an attractive synthetic method for primary anilines, using a hydrogen acceptor was indispensable to achieve satisfactory levels of selectivity in liquid-phase organic synthetic systems without photoirradiation. In this study, we developed a highly selective synthesis of primary anilines from cyclohexanones and NH 3 via efficient acceptorless dehydrogenative aromatization heterogeneously catalyzed by an Mg(OH) 2 -supported Pd nanoparticle catalyst in which Mg(OH) 2 species are also deposited on the Pd surface. The basic sites of the Mg(OH) 2 support effectively accelerate the acceptorless dehydrogenative aromatization via concerted catalysis, suppressing the formation of secondary amine byproducts. In addition, the deposition of Mg(OH) 2 species inhibits the adsorption of cyclohexanones on the Pd nanoparticles to suppress phenol formation, achieving the desired primary anilines with high selectivity.