Copper-Catalyzed Insertion of Diazo Compounds into Vinyl Hypervalent Iodine Reagents to Generate Allylic Esters

An unprecedented copper(I)-catalyzed vinylation of (donor)-acceptor diazo compounds with VinylBenziodoXolone reagents (VBX) as partners is reported. The transformation tolerates variation of both donor- and acceptor substituents on the diazo compounds, delivering the corresponding benzoylated allylic alcohol products in good to excellent yields. Through the development of a protocol for the synthesis of functionalized alkanes-, dienes- and enynes-substituted VBX reagents, a broad scope of substituents on the alkene could be accessed. The obtained products contain synthetically versatile functional groups, such as an aryl iodide, an ester and an allylic leaving group, enabling selective further modification.