An exocyclic π-system extension of the phenanthriporphyrin framework: towards azaaceneporphyrinoids

A facile method for the exocyclic pi-extension of the carbaporphyrinoid embedding phenanthrene moiety - phenanthriporphyrin - has been described. The reaction between 5,6-dioxophenanthriporphyrin and a series of aliphatic and aromatic amines provided a family of carbaporphyrinoids incorporating azaacene components. The H-1 NMR spectroscopic, electrochemical, and optical properties of azaaceneporphyrinoids strongly depend on the structure of the incorporated moiety. The pi-system extension of the attached azaacene subunit reduces the macrocyclic antiaromatic character.