One-electron oxidation of an organic molecule by B(C6F 5)3; Isolation and structures of stable non-para-substituted triarylamine cation radical and bis(triarylamine) dication diradicaloid
The methylene-bridged triphenylamine 2 has been oxidized to planar radical cation 2•+ by B(C6F5)3 or Ag+. Further reaction of 2•+[Al(ORF) 4]- and 2 with trace amounts of silver salt resulted in dication 32+, providing a rare example of structurally characterized bis(triarylamine) "bipolarons". 32+ can be directly prepared by the reaction of 3 with 2 equiv of Ag+. X-ray structural analysis together with theoretical calculation shows that 32+ has singlet diradical character and is analogous to Chichibabin's hydrocarbons. 2013 American Chemical Society.