Synthesis of Fused Pyrrolo-napthridinone via Ligand-free Copper Catalysed Ullmann (C-N coupling) Type Reaction

Fused pyrrole, pyridine with pyridinone components are known to possess many biological and pharmaceutical properties. Fused pyrrole with naptharidinone also has many potentials. A tandem approach of intramolecular lactamization and N-arylation using a copper catalyst to obtain a fused pyrrolo- naptharidinone has been developed. A ligand-free method has been proposed for cyclization and Ullmann (C-N coupling) type reaction in a single step. This approach will make it possible to synthesise pyrrolo- naphthyridinone N-aryl substituted natural product compounds without the need for extra additives.