Water Activation - Radical Hydrogen Atom Transfer to Unactivated pi-Systems

We demonstrate water activation by a photocatalytic phosphine-mediated radical process, generating a PR₃-H₂O radical cation intermediate, where both hydrogen atoms are used in the following chemical transformation through sequential cleavage of the O-H bonds.^1,2 P-radical cations can also be used to activate the cyanate anion³ and we will further show how phosphoranyl radicals can be turned into super electron donors.⁴ Moreover, P-radical cations can also be used for activation of nitroarenes⁵ and it will be discussed that nitroarenes are radical oxygenation reagents for Fe-catalyzed alkene hydrations.⁶ Further, a new radical amidation reagent is introduced and applications for the hydroamidation of complex alkenes will be demonstrated.⁷ Finally, Fe-catalyzed hydrohalogenations of alkenes are discussed.⁸

References

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