A highly efficient and selective chemo-divergent hydrogenation of cyclic carbonates is promoted by in situ generated poly(ionic liquid)-stabilized ruthenium nanoparticles (Ru@PIL) catalysts. Under solvent-free conditions, ethylene carbonate is transformed into either ethylene glycol and CH₄ or EtOH and CO₂, following a “direct hydrogenation” or a “hydrogenative decarboxylation” pathway, respectively.

Abstract

Cyclic carbonates, in particular ethylene carbonate (EC), are pivotal compounds across chemical sciences because of their unique properties. Although, their transformation into valuable products has attracted great attention, efficient and selective transformations remain challenging. In this work, we report a catalytic system composed of Ru nanoparticles (RuNPs) stabilized by poly(ionic liquids) (Ru@PIL), that enables the selective chemo-divergent hydrogenation of EC into either EtOH and CO₂ or EG and CH₄, under solvent-free conditions. Those transformations relied on the multi-task ability of poly(ionic liquids) (PILs), which provides efficient electro-steric protection of the NPs, good solubility in neat carbonates, and organocatalytic activity depending on the nature of the PIL counter-anions. Hence, PIL incorporating nucleophilic anions, such as I⁻, triggers the cascade transformation of EC into EtOH via a sequential decarboxylation-hydrogenation process. Conversely, in the presence of non-nucleophilic anions, the PIL is catalytically a spectator, yielding to the “direct hydrogenation” of EC by the RuNPs.