| Abstract
| - The following five antimony(V) tetraphenylporphyrins withσ-bonded antimony−carbon bonds were synthesized: [(TPP)Sb(CH3)2]+PF6-,[(TPP)Sb(OCH3)(OH)]+PF6-,[(TPP)Sb(CH3)(OH)]+ClO4-,[(TPP)Sb(CH3)(OCH3)]+ClO4-,and[(TPP)Sb(CH3)(F)]+PF6-.Each compound is stable toward air and moisture and hasahigh melting point (>250 °C). The electrochemistry andspectroelectrochemistry of these σ-bonded porphyrinswere examined in benzonitrile or dichloromethane containing 0.1 Mtetrabutylammonium perchlorate as supportingelectrolyte and the data compared to those for three previouslysynthesized OEP derivatives containing similarσ-bonded and/or anionic axial ligands. Each porphyrin shows tworeversible reductions and up to a maximun ofone oxidation within the potential window of the solvent.Spectroelectrochemical data indicate formation of aporphyrin π anion radical upon the first reduction as do ESR spectraof the singly reduced species. However, asmall amount of the Sb(III) porphyrin products may be generatedvia a chemical reaction following electrontranfer. An X-ray crystallographic analysis of[(TPP)Sb(CH3)(F)]+PF6-is also presented: monoclinic, spacegroup C2/c, Z = 8, a =24.068(5) Å, b = 19.456(4) Å, c =18.745(3) Å, β = 94.69(2)°, R =0.056.
- The followingfive antimony(V) tetraphenylporphyrins with σ-bondedantimony−carbon bonds were synthesized: [(TPP)Sb(CH3)2]+PF6-,[(TPP)Sb(OCH3)(OH)]+PF6-,[(TPP)Sb(CH3)(OH)]+ClO4-,[(TPP)Sb(CH3)(OCH3)]+ClO4-,and[(TPP)Sb(CH3)(F)]+PF6-.Each porphyrin shows two reversible reductions and up to a maximumof one oxidation within the potential window of the solvent.Spectroelectrochemical data indicate formation of a porphyrinanion radical upon the first reduction as do ESR spectra of the singlyreduced species. However, a small amount of the Sb(III)porphyrin products may be generated via a chemical reaction followingelectron transfer.
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