Glycerol-derived ionic liquids: a new family of high-potential renewable ionic solvents

Abstract

This study describes a new family of bio-based ionic liquids (ILs) derived from glycerol, designed to address the environmental and toxicity concerns associated with conventional ILs. Two synthetic routes, starting from glycidyl ethers or epichlorohydrin are proposed in order to obtain a series of [N₂0R]X ILs with varying alkyl chains (R) and anions (X⁻), including chloride, triflate, bistriflimide, formate, and lactate. Comprehensive characterization of the ILs has been carried out, revealing tunable physicochemical properties, such as density (1.03–1.40 g cm⁻³), viscosity (0.3–189 Pa s), and thermal stability (up to 672 K), influenced by structural modifications. The ILs demonstrated their applicability in two key applications: solubilizing hydroxycinnamic acids outperforming traditional solvents, and serving as recyclable media for Pd nanoparticle-catalyzed Heck–Mizoroki coupling, achieving quantitative yields and selectivity. These glycerol-derived ILs combine sustainability with functionality, offering a versatile platform for green chemistry applications.