An efficient nucleophilic addition reaction of indole derivatives with various synthesized azo-linked aldehydes to afford novel derivatives of diindolylmethane was carried out using a catalytic amount of L-proline, K10 and nanoFe 3 O 4 in aqeous media.

Efficient nucleophilic addition reactions of indole derivatives with various azo-linked aldehydes were carried out using Fe 3+montmorillonite K10 under solvent-free conditions to afford the corresponding diindolylmethanes in short reaction times and excellent yields.