Polystyrene-supported GaCl3 as a highly efficient and recyclable heterogeneous Lewis acid catalyst for one-pot synthesis of N-substituted pyrroles

A new and environmentally benign method for the preparation of N-substituted pyrroles from one-pot condensation reaction of 2,5-hexanedione with amines and diamines in the presence of polystyrene-supported gallium trichloride (PS/GaCl3) as a highly active and reusable heterogeneous Lewis acid catalyst is presented. This new protocol has the advantages of easy availability, stability, reusability and eco-friendly of the catalyst, high to excellent yields, simple experimental and work-up procedure.

Graphical abstractA new and environmentally benign method for the preparation of N-substituted pyrroles from one-pot condensation reaction of 2,5-hexanedione with amines and diamines using polystyrene-supported gallium trichloride (PS/GaCl3) as a highly active heterogeneous Lewis acid catalyst is presented. This protocol has the advantages of easy availability, stability, reusability and eco-friendly of the catalyst, high to excellent yields, simple experimental and work-up procedure.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Cross-linked polystyrene/GaCl3 complex was used as an efficient catalyst for the preparation of N-substituted pyrroles. ► The heterogeneous Lewis acid catalyst can be easily recycled and reused without significant loss of activity. ► Polystyrene-supported GaCl3 as catalyst leads to short reaction time, high yields of the products.