Gold-catalyzed cyclization of diynes: controlling the mode of 5-​endo versus 6-​endo cyclization : ​an experimental and theoretical study by utilizing diethynylthiophenes - Hansmann, Max M.; Tšupova, Svetlana; Rudolph, Matthias; Rominger, Frank; Hashmi, A. Stephen K. (Chemistry - a European journal, 2014)