Palladium-Catalyzed C-C Bond Activation/Suzuki Reaction of Methylenecyclobutanes

Main observation and conclusion Transition-metal catalyzed C-C bond activation is a formidable challenge owing to the high bond energy. We report here a novel palladium-catalyzed C-C bond activation manner of methylenecyclobutanes followed by subsequent Suzuki cross-coupling reaction affording multisubstituted indanes. The tandem reaction process involves intramolecular carbopalladation of double bond, beta-carbon elimination and intermolecular trapping of the transient sigma-alkylpalladium complex with boronic acids. A new TADDOL-derived phosphoramidite ligand bearing fluorine and silicon-based bulky groups is found to be efficient for C-C bond activation of methylenecyclobutanes.

Automated summary

In this study, a novel palladium-catalyzed C-C bond activation of methylenecyclobutanes followed by Suzuki cross-coupling reaction was reported, leading to the formation of multisubstituted indanes. The tandem reaction process involves intramolecular carbopalladation of double bond, beta-carbon elimination, and intermolecular trapping of the transient sigma-alkylpalladium complex with boronic acids. A new TADDOL-derived phosphoramidite ligand containing fluorine and silicon-based bulky groups was found to be efficient for C-C bond activation of methylenecyclobutanes.