Corroles with group 15 metal ions. Synthesis and characterization of octaethylcorroles containing As, Sb, and Bi ions in +3, +4, and +5 oxidation states

The synthesis, spectroscopic characterization, and electrochemistry of As, Sb, and Bi corroles are reported. The investigated complexes are represented by [(OEC)As-V(CH3)]+ClO4- and (OEC)M where M = As(III), Sb(III), or Bi(III) and OEC is the trianion of octaethylcorrole. The products of each redox reaction are characterized by W-vis and ESR spectroscopy. The first one-electron oxidations of (OEC)As and (OEC)Sb are metal-centered and result in the formation of [(OEC)As-IV](+) and [(OEC)Sb-IV](+). A second one-electron oxidations generates [(OEC)-As-V](2+) and [(OEC.)S-b(IV)](2+), the latter of which is slowly converted to a Sb(V) corrole, [(OEC)Sb-V](2+). The first one-electron oxidation of (OEC)Bi leads only to the Bi(III) pi-cation radical, but a second one-electron oxidation is proposed to give a Bi(IV) complex, [(OEC)Bi](2+). The first reduction of [(OEC)As-V(CH3)]+ClO4- is accompanied by loss of the sigma-bonded methyl ligand and formation of an As(III) complex.