Homogeneous Copper-Catalyzed Cycloisomerization Reaction of Allenynes: Rapid Access to Functionalized Pyrroles

Homogeneous transition-metal-catalyzed alkyne cascade cyclization reaction has attracted much attentions over the past decades. However, the relevant homogeneous transition-metal-catalyzed cyclization of allenynes has seldom been explored probably due to noticeable chemo-, regio-, and stereoselectivity. Described herein is an efficient homogeneous copper-catalyzed cycloisomerization reaction of allenynes, thus leading to a practical and atom-economic access to an array of valuable functionalized pyrroles by formal [3 + 2] cycloaddition via Cu-containing all-carbon 1,4-dipoles.