10.1021/acs.orglett.6b01376.s001 Jacob R. Stepherson Jacob R. Stepherson Caitlan E. Ayala Caitlan E. Ayala Thomas H. Tugwell Thomas H. Tugwell Jeffrey L. Henry Jeffrey L. Henry Frank R. Fronczek Frank R. Fronczek Rendy Kartika Rendy Kartika Carbazole Annulation via Cascade Nucleophilic Addition–Cyclization Involving 2‑(Silyloxy)pentadienyl Cation American Chemical Society 2016 cation ether functionalized carbazoles indole intramolecular dehydrative cyclization Carbazole Annulation Silyloxy cascade reactions strategy intermediate sequence synthesis Nucleophilic silyloxy Br ønsted acid catalysis silyl regioselective nucleophilic addition ionization Cascade hydroxy enol yield Cation electrophilic species scaffold 2016-06-03 23:45:14 Journal contribution https://acs.figshare.com/articles/journal_contribution/Carbazole_Annulation_via_Cascade_Nucleophilic_Addition_Cyclization_Involving_2_Silyloxy_pentadienyl_Cation/3413314 We report a new strategy toward the synthesis of highly functionalized carbazoles via 2-(silyloxy)­pentadienyl cation intermediates, which were generated upon ionization of vinyl-substituted α-hydroxy silyl enol ethers under Brønsted acid catalysis. These electrophilic species were found to readily undergo cascade reactions with substituted indoles to generate carbazole molecular scaffolds in good yields via a sequence of regioselective nucleophilic addition, followed by intramolecular dehydrative cyclization.