A meso-Tetraaryl-21-carbaporphyrin: Incorporation of a Cyclopentadiene Unit into a Porphyrin Architecture

Angew Chem Int Ed Engl. 2019 Apr 23;58(18):6089-6093. doi: 10.1002/anie.201901808. Epub 2019 Apr 1.

Abstract

Incorporation of a cyclopentadiene moiety into the meso-tetraarylporphyrin framework, using 1,3-bis(arylhydroxymethyl)ferrocene as a synthon, resulted in the rational synthesis of a meso-tetraaryl-21-carbaporphyrin. The molecular design preserves all essential virtues of the original tetrapyrrolic architecture of meso-tetraarylporphyrin, including the perfect match between the ionic radii of an inserted metal and the size of the macrocyclic (CNNN) core, and steric protection provided by thoughtfully chosen meso-aryl substituents. Its protonation of the inner core reveal an adjustable (trigonal versus tetrahedral) geometry.

Keywords: ferrocene; palladium; porphyrinoids; structure elucidation; synthons.