Green Synthesis of Indeno[1,2-b]quinoxalines Using β-Cyclodextrin as Catalyst.

An efficient, mild, and green method was developed for the synthesis of indeno[1,2-b]quinoxaline derivatives via o-phenylenediamine (OPD) and 2-indanone derivatives utilizing β-cyclodextrin (β-CD) as the supramolecular catalyst. The reaction can be carried out in water and in a solid state at room temperature. β-CD can also catalyze the reaction of indan-1,2-dione with OPD with a high degree of efficiency. Compared to the reported methods, this procedure is milder, simpler, and less toxic, making it an eco-friendly alternative. In addition, the β-CD can be recovered and reused without the loss of activity.