Rueping and successfully reproduced by us. The observation that quinolines bearing small aliphatic groups are excellent substrates for simple catalysts, yet no good substrates for the confined nanohoop catalyst, is counterintuitive and suggests that specific non-covalent effects dictate reaction outcomes. In an effort to gain a tentative understanding of the unexpected, low reactivity towards alkyl quinolines, we carried out several experiments. Given that the strong binding of substrate and/or product to the active catalytic site is a plausible mechanism for catalyst deactivation, we tested