Carbon-carbon sigma-bond activation is a contemporary challenge for organometallic chemistry and catalysis. Herein, we disclose a new alkene carboacylation reaction initiated by quinoline-directed, rhodium-catalyzed C-C sigma bond activation. The alkene carboacylation allows for the construction of all-carbon quaternary centers, with a broad substrate scope, providing access to carbocyclic and heterocyclic ring systems in good to excellent yields.