Synthesis of functionalized benzimidazoles via oxidative tandem quartic C–H aminations and cleavage of C–N and C–C bonds†
Abstract
Via aerobic copper-catalyzed tandem quartic C–H aminations, we herein present an unprecedented approach for the synthesis of functionalized benzimidazoles from aniline derivatives and 2-substituted cyclic amines. The cyclic amines act as the CN building blocks and are involved in the annulation reaction by cleavage of inert α-C–N and β-C–C bonds. The synthetic protocol features high selectivity, no need for specific aminating agents, mild conditions, and the use of a naturally abundant [Cu]/O2 catalyst system.