A highly efficient one-pot, two-step microwave-assisted procedure was applied for the rapid and green synthesis of benzo[a]phenazine annulated heterocyclic ring systems from the three- or four-component condensation reactions of 2-hydroxynaphthalene-1,4-dione, o-phenylenediamine, aromatic aldehydes and 1,3-indandione using L-proline as a bifunctional organocatalyst in water. This new procedure has a number of advantages such as high yields, very short reaction times, operational simplicity, simple work-up procedures and avoidance of hazardous or toxic catalysts and organic solvents. Moreover, the catalyst can be recovered and reused several times without much loss of its performance.
Microwave Assisted One-Pot Green Synthesis of Silver Nanoparticles Using Leaf Extracts from Vigna Unguiculate: Evaluation of Antioxidant and Antimicrobial Activities