Citrate trisulfonic acid as a novel, recyclable, and heterogeneous organocatalyst for the one-pot synthesis of ۴-iminoquinolines

Citrate trisulfonic acid (CTSA), as a novel, heterogeneous and organocatalyst, was applied for an efficient synthesis of ۴-iminoquinolines using ۲-aminobenzonitrile, active methylenes and orthoesters under solvent-free conditions. CTSA was synthesized via the reaction of trisodium citrate and chlorosulfonic acid in high purity. The catalyst was characterized using FT-IR, NMR and Mass spectra. The present method offers several advantages including high yields, short reaction time, and reusability of the catalyst and simple purification of the products.

Keywords:

Citrate trisulfonic acid , Organocatalyst , Heterogeneous catalysis , ۴- Iminoquinolines , Acid catalysis