The Model System: Our choice of initial catalyst is a synthetic porphyrin derivative, HM1 in Figure , which was developed by Groves et al. and demonstrated to enhance hydrogen abstraction reactions in aqueous solutions. The rate-enhancement capability of HM1 was later shown to originate in the LEF of the charged peripheral substituents. For the supramolecular scaffold, we selected the porous organic cage (Figure ), which was synthesized by Kim et al, and named porphyrin box, PB-1 . As was shown by Kim et al, PB-1 possesses exceptional chemical stability and applicability; including selective gas sorption, encapsulation of guest molecules, etc. Importantly, such porous organic cages were reported to preserve their stability even after post-synthetic modification of some functional groups of such cages. Therefore, we deem this supramolecular scaffold to be an ideal starting platform that can be selectively modified (see SI, Figure , S2) for tailoring the LEF along the reaction axis of HM1, as well as for encapsulating target substrates for oxidation.