Visible Light-Mediated Formal Alkylation and [4+1]-Cycloaddition Strategies of Silyl Enol Ethers with Aryldiazoacetates

Reaction sequences of visible light-mediated cycloaddition/acidic treatment between silyl enol ethers and aryldiazoacetates allow the preparation of γ-keto esters and 2-cyclopentenones.