Selective hydrogenation of nitroarenes using an electrogenerated polyoxometalate redox mediator.

The 2-electron reduced form of the polyoxometalate silicotungstic acid (H4 [SiW12 O4 ]) is shown to be an effective and selective hydrogenation agent for a range of nitroarenes without the need for any co-catalyst. The ease of generation of the active species and its recyclability suggest that a new approach to this important class of chemical conversions is possible.