Colorful Friedel-Crafts chemistry of meso-tetraarylporphyrins. An unexpected route to porphyrinic spiro dimers.
Under Friedel-Crafts conditions, meso-tetraarylporphyrins give porphyrin spiro dimers in good yield. This reaction involves acylation, acid-catalyzed cyclization, and dimerization. A stable dimer possessing three additional six-membered rings could be isolated and its structure determined. By modifying the substrate and reagents, intermediates could be isolated and characterized. The reactivity of the substrates, the side-reactions, and the concentration requirements to form the dimers, all explain why this reaction remained apparently unexplored in the widely used meso-tetraarylporphyrin series. [reaction: see text]
Jeandon
Christophe
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Faculté de Chimie, UMR 7123 CNRS, Université Louis Pasteur, 1 rue Blaise Pascal, 67000 Strasbourg, France.
Ruppert
Romain
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Richeter
Sébastien
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Callot
Henry J
HJ