کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5217725 | 1383304 | 2013 | 11 صفحه PDF | دانلود رایگان |
2-Bromo-1-aryl substituted indenes can be synthesized from 1,2-diaryl substituted gem-dibromocyclopropanes via a domino reaction sequence. The cascade reaction involves silver(I) promoted ionization and 2Ï-disrotatory electrocyclic ring-opening, followed by a 4Ï-conrotatory electrocyclic ring closing reaction of the allylic carbocation intermediate. Reaction conditions utilize silver tetrafluoroborate (AgBF4) in dichloroethane at 65 °C. Selectivity effects for the electrocyclization were also studied. The 2-bromoindenes can be further functionalized using cross-coupling reactions, such as the Suzuki-Miyaura protocol. The alkene Ï-bond of the indenes can also be isomerized to give the thermodynamically more stable 2-bromo-3-aryl-1H-indene isomers using triethylamine in dichloromethane at room temperature.
Journal: Tetrahedron - Volume 69, Issue 41, 14 October 2013, Pages 8758-8768