Ionic Liquid - Based Green Solvents for Sustainable Organic Synthesis

Abstract

Ionic liquids (ILs) have emerged as promising green solvents for sustainable organic synthesis because of their negligible vapor pressure, high thermal stability, tunable polarity, and ability to function simultaneously as solvents and catalysts. In recent years, research—including significant contributions from Indian chemists—has focused on replacing volatile organic compounds with ionic liquid systems to achieve safer, energy-efficient, and environmentally benign synthetic pathways. This research paper reviews ionic liquid–based green solvent systems used in sustainable organic synthesis, covering their structural principles, physicochemical properties, synthesis approaches, reaction applications, recyclability, and environmental considerations. Methodologies discussed include solvent design, catalytic reaction optimization, and performance evaluation through yield, selectivity, and recyclability studies. Results from recent literature show that IL-based systems significantly improve reaction efficiency, reduce waste generation, and support multicomponent and heterocyclic synthesis. The discussion highlights challenges such as toxicity assessment, cost, and large-scale implementation while outlining future directions in bio-based ionic liquids and hybrid green solvent systems.