Palladium-Catalyzed Trimethylenemethane Cycloaddition of Olefins Activated by the σ-Electron-Withdrawing Trifluoromethyl Group.
α-Trifluoromethyl-styrenes, trifluoromethyl-enynes, and dienes undergo palladium-catalyzed trimethylenemethane cycloadditions under mild reaction conditions. The trifluoromethyl group serves as a unique σ-electron-withdrawing group for the activation of the olefin toward the cycloaddition. This method allows for the formation of exomethylene cyclopentanes bearing a quaternary center substituted by the trifluoromethyl group, compounds of interest for the pharmaceutical, agrochemical, and materials industries. In the diene series, the cycloaddition operates in a [3 + 4] and/or [3 + 2] manner to give rise to seven- and/or five-membered rings. This transformation greatly improves the scope of the TMM cycloaddition technology and provides invaluable insights into the reaction mechanism.
Department of Chemistry Stanford University , Stanford, California 94305-5080, United States.
Barry M
BM
Trost
Department of Chemistry Stanford University , Stanford, California 94305-5080, United States.
Laurent
L
Debien
D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D061565:Cycloaddition Reaction; D004583:Electrons; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*
D000475:Alkenes; C522820:trimethylenemethane; D010165:Palladium; D008697:Methane