Tandem aza-Michael addition-vinylogous aldol condensation: synthesis of N-bridged pyridine fused quinolones

Synthesis of Multifused Pyrrolo[1,2-a]quinoline Systems by Tandem Aza-Michael-Aldol Reactions and Their Application to Molecular Sensing Studies

Herein, we have presented a weak acid-promoted tandem aza-Michael-aldol strategy for the synthesis of diversely fused pyrrolo[1,2-a]quinoline (tricyclic to pentacyclic scaffolds) by the construction of both pyrrole and quinoline ring in one pot. The described protocol fabricated two C-N bonds and one C-C bond in the pyrrole-quinoline rings which have been sequentially formed under transition-metal-free conditions by the extrusion of eco-friendly water molecules. A ketorolac drug analogue has been synthesized following the current protocol, and one of the synthesized tricyclic pyrrolo[1,2-a]quinoline fluorophores has been used to detect highly toxic picric acid via the fluorescence quenching effect.