Base-Promoted and Copper(I)-Catalyzed Tandem Cyclization-C(sp)-N Coupling of Vinyl Malononitriles with -Nitrochalcones: Access to Acridones and their Fused Derivatives.

An efficient CsCO-promoted and copper(I)-catalyzed double cyclization of -nitrochalcones with vinyl malononitriles for the access to a variety of tri- and tetra-substituted acridones and their fused derivatives with a value-added CN group has been developed for the first time. This one-pot operation proceeds through a Michael-cyclization-aromatization, followed by regioselective -amination via nucleophilic aromatic substitution (SAr) reaction, resulting in two C═C bonds and a C-N bond for acridone ring synthesis. This economic strategy based on 100% carbon atoms ensures the successive formation of two rings in a one-pot operation, good to high yields, a wide range of substrates, and good tolerance of functionalities.