Co(II)-Catalyzed Regioselective Cross-Dehydrogenative Coupling of Aryl C–H Bonds with Carboxylic Acids

Abstract

A cobalt(II)-catalyzed regioselective aryl C−H bond oxygenation between arenes and aryl or aliphatic carboxylic acids under bidendate-chelation assistance is developed. This method provides an efficient approach to acyoxy-substituted arenes with a broad range of functional group tolerance. Furthermore, this reaction system could be further applied to the preparation of polyfunctional naphthylenes.

A comprehensive overview of directing groups applied in metal-catalysed C–H functionalisation chemistry

“…In 2017, Zeng reported a Co-catalysed cross dehydrogenative coupling (CDC) between picolinamide derivatives with aliphatic and aromatic carboxylic acids ( Scheme 95C ). 573 It is worth mentioning that this transformation was mainly restricted to naphthalene compounds and only two N -benzyl substituted 2-pyridinecarboxamides were functionalised as well, although in low yields (25 and 37%). Acetoxylation at the remote ε-C(sp 2 )–H bond was studied by Babu using this bidentate DG (not shown).…”

Direct ortho‐Acyloxylation of Arenes and Alkenes by Cobalt Catalysis

“…Very recently, cobalt catalysis assisted by bidentate directing groups was also applied in C−H bond activation reactions to realize a variety of useful transformations . Inspired by the above encouraging achievements and our continuing endeavors on transition metal‐catalyzed directed C−H bond functionalization, we are intrigued by the cobalt‐catalyzed acyloxylation reaction of arenes and alkenes with readily accessible carboxylic acids . It was observed that the direct acyloxylation of arenes and alkenes could be realized with the assistance of an 8‐aminoquinolyl auxiliary to lead to the corresponding esters in high yields.…”

Regioselective C−H Functionalization of Naphthalenes: Reactivity and Mechanistic Insights

“…Wu's group reported a palladium‐catalyzed acylation of naphthylamines with acyl chlorides . In 2017, Zeng's group demonstrated a cobalt‐catalyzed coupling of naphthylamines with carboxylic acids . These two methods offers an easy access to 1,8‐disubstitued naphthalenes which could be further functionalized.…”