Base-Free Dehydrogenation of Aqueous and Neat Formic Acid with Iridium(III) Cp*(dipyridylamine) Catalysts.

The selective dehydrogenation of formic acid by iridium(III) Cp*(dipyridylamine) catalysts is reported. The electron-enriched catalyst [IrIII Cp*{(4-dimethylaminopyridin-2-yl-κΝ)(pyridin-2'-yl-κΝ)amine}(OSO3 )] gave the best performances enabling the base free dehydrogenation of aqueous and neat formic acid. In both cases the reaction was selective with no carbon monoxide detectable. The IrIII complex demonstrated latent behavior, which may be of practical utility. Experimental results suggest an outer-sphere interaction with the ligand.