The synthesis and characterization of a new supramolecular assembly I, wherein photoinduced electron transfer through non-covalent interactions may be probed, is reported. Ensemble I is based on supramolecular contacts between the phenolic hydroxyl groups of a calix[4]arene-substituted Zn(II) metalloporphyrin photodonor 1a and the carbonyl groups of a benzoquinone acceptor 6. Ensemble I is formed with a K a of 70+/-10dm 3 mol - 1 in CDCl 3 as judged by 1 H NMR spectroscopic analysis. Upon irradiation of the porphyrin subunit of I at 400nm, a photoinduced intramolecular electron transfer from the Zn(II) metalloporphyrin to the benzoquinone occurs with a rate constant of 3.3x10 1 0 s - 1 . Two phenolic hydroxyl groups of the calix[4]arene serve not only as tweezers to capture the benzoquinone by two-point hydrogen bonding fixation, but also as useful building blocks in the construction of non-covalent donor-acceptor electron transfer model systems.