Gold-Catalyzed Dimeric Cyclization of Isoeugenol and Related 1-Phenylpropenes in Ionic Liquid: Environmentally Friendly and Stereoselective Synthesis of 1,2,3-Trisubstituted 2,3-Dihydro-1H-indenes

Gold-catalyzed dimerization of isoeugenol and related 1-phenylpropenes in ionic liquid enabled environmentally friendly, stereo­selective synthesis of 1,2,3-trisubstituted 2,3-dihydro-1 H -indenes. Dimerization of isoeugenol or isohomogenol afforded diisoeugenol or diisohomogenol, respectively, with α-configuration, whereas dimerization of α-asarone furnished diasarone with γ-configuration.