Download Poster (1.2 MB)
Carbaporphyrinoids are porphyrin analogues where one or more of the internal nitrogen atoms have been replaced by carbons. Many examples of these systems have been reported and these show diverse reactivity and modified spectroscopic properties. In order to further extend this field, the formation of carbaporphyrinoid systems incorporating heterocyclic subunits is being investigated. Specifically, porphyrinoid 1 incorporating a 4H-quinolinizin-4-one unit was targeted for synthesis. A quinolizinone diester 2 was synthesized from ethyl 2-pyridylacetate and diethyl ethoxymethylenemalonate. Refluxing 2 with conc. hydrochloric acid afforded quinolizinone 3 and subsequent Vilsmeier-Haack formylation gave the related dialdehyde 4. Condensation of 4 with tripyrrane 5 using the MacDonald-type “3 + 1” approach gave the targeted oxyquinoliziniporphyrin 1. Proton NMR spectroscopy indicated that this novel porphyrinoid has intermediary aromatic character. Ongoing studies are being directed towards the metalation, structural and spectroscopic characterization of 1.
Cramer, Emma, "Synthesis of Oxyquinoliziniporphyrin" (2020). Chemistry. 2.