Reductive Electrophotocatalysis: Merging Electricity and Light To Achieve Extreme Reduction Potentials

We describe a new electrophotocatalytic strategy that harnesses the power of light and electricity to generate an excited radical anion with a reducing potential of −3.2 V vs SCE, which can be used to activate substrates with very high reduction potentials (E red ≈ −1.9 to −2.9 V). The resultant aryl radicals can be engaged in various synthetically useful transformations to furnish arylboronate, arylstannane, and biaryl products.