Silica-based sulfonic acid (MCM-41-SO3H): a practical and efficient catalyst for the synthesis of highly substituted quinolines under solvent-free conditions at ambient temperature

Abstract

In this work, a variety of highly substituted quinolines were readily synthesized via Friedlander annulation using Brönsted acid silica-based sulfonic acid as a modified catalyst under solvent-free conditions at room temperature. This efficient procedure has the advantages of giving the target compounds in high yields, short reaction times, simple workup procedure, reusability of the catalyst, and environmentally benign conditions.

Keywords

• MCM-41-SO3H
• Silica-based sulfonic acid
• Solvent-free
• Quinolines
• Friedlander reaction