New Pathways for the Dual Gold-Catalyzed Cyclization of Diynes

The reaction of thiophene‐based diynes with dual‐activation gold catalysts can provide cyclobutene derivatives or different polycycles by selective C−H insertion reactions. Also, the first σ,π‐digold diyne complex was obtained in a stoichiometric reaction, providing insight into the dual activation mechanism. The new products were unambiguously identified by X‐ray single‐crystal structure analysis. Taking the strain: Dual‐activation gold catalysts can provide cyclobutene derivatives or different polycycles by selective C−H insertion reactions (see scheme). The reaction mechanisms were investigated with different substrates, and products were characterized by X‐ray crystallography.