Electrochemistry and spectral characterization of arsenic porphyrins with 6-bonded axial ligands.: X-ray crystallographic analysis of [(OEP)As(F)2]+PF6-, [(OEP)As(CH3)(OCH3)]+ClO4- and [(OEP)As(C2H5)2]+PF6-

The electrochemistry of nine arsenic(V) octaethylporphyrins is reported in benzonitrile or dichloromethane containing 0.1 M tetra-n-butylammonium perchlorate as supporting electrolyte and the results compared to data for phosphorus and antimony porphyrins containing a similar set of sigma-bonded and/or anionic axial ligands. The investigated compounds are divided into three groups based on the nature of the axial ligands and are represented as [(OEP)As(R)(R')](+) (group I), [(OEP)As(R)(X)](+) (group II) and [(OEP)As(F)(2)](+) (group III) where R and R' = CH3 or C2H5, X = OH-, OCH3, OC2H5-, OC3H7- or NHC4H9- and OEP = the dianion of octaethylporphyrin. Each compound was characterized in its neutral, oxidized and reduced form by UV-visible and ESR spectroscopy. An X-ray crystallographic analysis of [(OEP)As(F)(2)]+PF6-, [(OEP)As(CH3)(OCH3)](+) ClO4- and [(OEP)As(C2H5)(2)]+PF6- is also presented. Copyright (C) 2002 Society of Porphyrins & Phthalocyanines.