| Abstract
| - We describe the preparation of six diketones based on the frameworks of five bis-naphthoporphyrinsand one perinaphthoporphyrin. All diketones derive from meso-tetraarylporphyrins havingincorporated two carbonyl groups, each one connected to one β-pyrrole carbon and one ortho carbonatom from a meso-aryl group. These compounds were all produced in good yield by intramolecularFriedel−Crafts acylation, either from porphyrins meso-substituted by o-carboxyphenyl or o,o‘-dicarboxyphenyl substituents or from porphyrins bearing carboxy groups attached to the pyrrolicβ-positions. Although the former reaction does not show significant regioselectivity when run onnickel complexes, the opposite is true for the corresponding free bases. All diketones show aspectacular bathochromic shift of the UV−vis absorption, the longest wavelength bands absorbingin the 700−825 nm range. Two compounds were structurally characterized by X-ray diffraction. Inthe case of the diketone, whose carbonyl groups are attached to vicinal pyrrolic β-positions, asignificant intermolecular interaction between the two carbonyl groups and an aromatic hydrogenatom was detected.
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