177417-17-3Relevant articles and documents
Synthesis and Electrochemistry of Tetraphenylporphyrins Containing an Antimony-Carbon σ-Bond
Kadish, Karl M.,Autret, Marie,Ou, Zhongping,Akiba, Kin-Ya,Masumoto, Shuji,Wada, Ryosuke,Yamamoto, Yohsuke
, p. 5564 - 5569 (2008/10/09)
The following five antimony(V) tetraphenylporphyrins with σ-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 has a high melting point (>250 °C). The electrochemistry and spectroelectrochemistry of these σ-bonded porphyrins were examined in benzonitrile or dichloromethane containing 0.1 M tetrabutylammonium perchlorate as supporting electrolyte and the data compared to those for three previously synthesized OEP derivatives containing similar CT-bonded and/or anionic axial ligands. Each porphyrin shows two reversible reductions and up to a maximun of one oxidation within the potential window of the solvent. Spectroelectrochemical data indicate formation of a porphyrin π anion radical upon the first reduction as do ESR spectra of the singly reduced species. However, a small amount of the Sb(III) porphyrin products may be generated via a chemical reaction following electron tranfer. An X-ray crystallographic analysis of [(TPP)Sb(CH3)(F)]+PF6- is also presented: monoclinic, space group C2/c, Z = 8, a = 24.068(5) A, b = 19.456(4) A, c = 18.745(3) A, β= 94.69(2)°, R = 0.056.
