Electrochemically switchable supramolecular complex between bisporphyrin cleft and electron-deficient aromatic guest

The host–guest complexation between bisporphyrin cleft 1 and flat aromatic guest 2 was controlled by an electrochemical reaction. The first oxidation potentials of 1 showed the anodic shift upon the addition of 2. On the basis of the square scheme, the association constant of 1 with 2 was estimated to be at least 50 times larger than that of cation radical 12·+ with 2. This demonstrated that the electrochemical oxidation obviously reduced the binding ability of 1. The reversible nature of the switchable complexation between 1 and 2 was confirmed by cyclic voltammetry. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:590–593, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20702