Palladium-catalyzed intermolecular formal [3+2] cyclization/C–H alkylation of polyfluoroarenes†
Abstract
Until now, the σ-alkylpalladium species in C–H alkylation of polyfluoroarenes were largely limited to palladium-catalyzed domino intramolecular cyclization of o-iodophenol-derived allyl ethers or N-aryl acrylamides. Herein, we disclose a sequential three-component intermolecular carbopalladation/Heck cyclization/intermolecular C–H bond functionalization of o-iodostyrenes, polyfluoroarenes, internal alkynes or oxanorbornadiene (ONBD), thus assembling various alkylated polyfluoroarene derivatives containing an indene skeleton. Additionally, dialkylated polyfluoroarenes containing two indenes can be constructed by the dual reaction strategy.