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

Cu II metalations of carbaporphyrins 1 - 4 gave the corresponding Cu II complexes 1-Cu , 2-Cu , 3-Cu , and 4-Cu with varying degrees of distortions in Cu II square-planar coordination. Upon treatment with Cu(OAc) 2 , 1-Cu was inert but 2-Cu and 3-Cu gave the respective O-atom-inserted complexes 2-OCu and 3-OCu . Further, 3-Cu and 4-Cu were converted to meso -methoxynickel(II) porphyrins 3-OMe and 4-OMe , respectively, via treatment with Cu(OAc) 2 in methanol. meso -Hydroxynickel(II) porphyrin 3-OH was obtained by the treatment of 3-OCu by acetic acid. The treatment of 4-Cu with Cu(OAc) 2 in the presence of acetic acid gave 5,15-diketoporphyrinogen 4-O . Cu II complexes of carbaporphyrins became more reactive with an increased distortion in Cu II square-planar coordination.