New biobased tetrabutylphosphonium ionic liquids: synthesis, characterization and use as a solvent or co-solvent for mild and greener Pd-catalyzed hydrogenation processesElectronic supplementary information (ESI) available. See DOI: 10.1039/c6ra23056c

Phosphonium-based Ionic Liquids (PhosILs) with natural organic derived anions ( l -lactate, l -tartrate, malonate, succinate, l -malate, pyruvate, d -glucuronate, d -galacturonate, ferulate, p -coumarate) were easily prepared by acid-base method from tetrabutylphosphonium hydroxide and an excess of the corresponding acid with good yields. Their characterization was realized through classical NMR, IR and elemental analysis techniques; their viscosity and ATG parameters were also determined. These ionic liquids showed good performance and recyclability in the selective Pd-catalyzed hydrogenation of alkenes, polyenes like linoleic acid and enantioselective hydrogenation of unsaturated ketones such as isophorone at room temperature under atmospheric H 2 pressure. Furthermore, NMR studies leading to computational calculations were performed to establish easily the composition of the resulting mixture obtained through the hydrogenation of linoleic acid. Phosphonium-based ionic liquids with natural organic derived anions were easily prepared and showed good performance and recyclability in Pd-catalyzed hydrogenation processes at room temperature under atmospheric H 2 pressure.