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Abstract

For studying intramolecular electron‐transfer reactions, three groups of double‐ and single‐bridged porphyrin‐quinone cyclophanes 1–4, 5–9, and 11–14, resp., with gradual variation of quinone acceptor strengths were synthesized. As key intermediates for building up the porphyrin‐cyclophane skeleton the correspondingly 3,6‐substituted 1,4‐bis[4‐(2‐formylphenyl)‐butyl]‐2,5‐dimethoxybenzenes 15–20 were synthesized. Condensation with pyrrole yielded the doubly bridged porphyrin cyclophanes 42–45; via the bis(dipyrrolylmethyl) derivatives 46–51 and 64–67 the single‐bridged porphyrin cyclophanes 58–63 and 72–75 were obtained by acidic condensation with triethyl formate. Cleavage of the methoxy groups and oxidation yielded the corresponding porphyrin‐quinone systems. Some magnesium and zinc complexes of these cyclophanes are described. Spectroscopic data (MS, 1H NMR) are reported in support of the proposed structures.