Facile [2+2] Cycloaddition of DDQ to an Alkyne: Synthesis of Pyrrolyl- and Indolylbicyclo[4.2.0]octadienes from C-Ethynylpyrroles or C-Ethynylindoles - Trofimov, Boris A.; Sobenina, Lyubov’ N.; Stepanova, Zinaida V.; Ushakov, Igor’ A.; Sinegovskaya, Lidiya M.; Vakul’skaya, Tamara I.; Mikhaleva, Al’bina I. (Synthesis, 2010)