A novel and efficient synthesis of indoles by using a three-component reaction of arylamine, arylglyoxal, and 4-hydroxycoumarin

Indole cores are an important class of heterocyclic compounds found in natural products, drug molecules, and functional materials.1 They have been attention in recently years due can be exhibit a wide spectrum of biological activity such as the anti-inflammatory,2 anti-proliferative, and platelet aggregation inhibitory activities.3 Herein, we describe efficient and novel method for the synthesis of indole derivatives 4 via appropriate arylamine 1, arylglyoxal 2, and 4-hydroxycoumarin 3 in ethanol solvent at reflux conditions for 12 h. (Fig. 1). Metal-free catalyst, eco-friendly solvents, and excellent yields (80-93 %) are advantages of the protocol. All the synthesized compounds were unknown to the best of our knowledge and were characterized by 1H and 13C- NMR, IR and melting points

Keywords:

Indole derivatives , Arylamine , Arylglyoxal , 4-Hydroxycoumarin