Catalytic Conversion of N‑Heteroaromatics to Functionalized Arylamines by Merging Hydrogen Transfer and Selective Coupling

To date, although
tremendous advances have been made in N-heteroaryl
C–H functionalization, there remain significant unmet challenges
in the deconstruction of extensively applied but poorly reactive N-heteroaromatics
to useful frameworks. Here, by a strategy merging hydrogen transfer
and selective coupling, we present a ruthenium-catalyzed deconstruction
of N-heteroaromatics to functionalized arylamines with 2-aminoaryl
methanols. The reaction is achieved via sequential functionalization
of the β and α sites of the initially formed N-heteroarenium
salts followed by a C–N cleavage, which proceeds with the striking
features of broad substrate scope, excellent functional group tolerance,
high chemoselectivity and atom efficiency, and suitability for a streamlined
synthesis of some biomedical molecules. The strategy utilized will
pave the way for further development of catalytic transformations
of inert organo systems to functional frameworks.