Redox active ionic liquid as efficient mediator and solvent for visible light-driven B12 catalytic reactions

The redox active ionic liquid, 1-ethyl-4-(methoxycarbonyl)pyridinium bis(trifluoromethanesulfonyl)amide (RIL), was synthesized from its iodide form by an anion exchange reaction of Li(NTf2) with viscos liquid (eta = 122 cP at 25 degrees C) and characterized by NMR, IR, and elemental analysis. The compound showed reversible redox couples at -0.65 V and -1.48 V vs. Ag/AgCl and worked as an electron mediator in the B-12 complex/[Ru(bpy)(3)]Cl-2 photosensitizer catalytic system under visible light irradiation. The catalytic efficiency in the RIL was higher than those in DMF, MeOH, and the redox inactive ionic liquid, 1-butyl-3-methyl imidazolium bis(trifluoromethylsulfonyl)amide. (C) 2019, Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V.