Copper(II) Carbaporphyrins: Oxygenation Reactivities Dependent upon Coordinating Structures.

Cu metalations of carbaporphyrins - gave the corresponding Cu complexes , , , and with varying degrees of distortions in Cu square-planar coordination. Upon treatment with Cu(OAc), was inert but and gave the respective O-atom-inserted complexes and . Further, and were converted to -methoxynickel(II) porphyrins and , respectively, via treatment with Cu(OAc) in methanol. -Hydroxynickel(II) porphyrin was obtained by the treatment of by acetic acid. The treatment of with Cu(OAc) in the presence of acetic acid gave 5,15-diketoporphyrinogen . Cu complexes of carbaporphyrins became more reactive with an increased distortion in Cu square-planar coordination.