The rhodium-catalyzed intramolecular carboacylation of quinolinyl ketones serves as an ideal subject for the mechanistic study of carbon-carbon bond activation. Combined kinetic and NMR studies of this reaction allowed the identification of the catalytic resting state and determination of the rate law, C-12/C-13 kinetic isotope effects, and activation parameters. These results have identified the activation of a ketone-arene carbon-carbon single bond as the turnover-limiting step of catalysis and provided quantitative detail into this process.