Optical and magnetic resonance studies of the interaction of metallotetraphenylchlorin and octaethylporphyrin with trinitrofluorenone

Abstract

The interaction of metallo derivatives of tetraphenylchlorin (TPC) and octaethylporphyrin (OEP) with 2,4,7-trinitrofluorenone (TNF) is described in terms of 1 : 1 molecular complexes. The binding constants vary as CuOEP>ZnOEP>CuTPC>ZnTPC and this variation is accounted in terms of the structure of the macrocycle and the substituents presen on it. ESR studies of the complexes reveal that the π-complexation results in changes in the electronic structure of the central metal ion. The magnitude of different proton shifts of the acceptor in ¹H NMR spectra of the complexes are used to arrive at the possible solution structure of the complexes.