Diversified Synthesis of Furans by Coupling between Enols/1,3‐Dicarbonyl Compounds and Nitroolefins: Direct Access to Dioxa[5]helicenes

Abstract A versatile method for the diversified synthesis of furans and arenofurans has been developed that proceeds through K 2 CO 3 ‐promoted cyclization between enols/1,3‐dicarbonyl compounds and nitroolefins at reflux in EtOH. This facile method has been successfully employed in the synthesis of benzotrifuran derivatives, which are useful hole‐transporting materials. This procedure also provides direct access to dioxa[5]helicenes. This reaction offers a broad substrate scope, uses an inexpensive base and environmentally benign solvent, and is operationally simple.