
%0 Journal Article
%A Garrard, WNC 
%A Thomas, FG 
%T On the Electrochemical-Behavior of Pyrylium Ions at the Mercury-Electrode. II. Aromatically Substituted Ions in Acetonitrile
%J Australian Journal of Chemistry
%D 1986/06/01
%V 39
%N 6
%P 865-884
%K 
%R https://doi.org/10.1071/CH9860865
%U https://www.publish.csiro.au/paper/CH9860865 
%X The electrochemical behaviour of the 2,4,6-triphenylpyrylium ( tpp +) and 7-phenyl-5,6,8,9-tetrahydrodibenzo[ c,h ] xanthylium (thx+) ions in acetonitrile in the presence of 0.1 M tetrabutylammonium perchlorate is reported. The reduction of both ions proceeds by two, one-electron steps. The initial product of the first reduction is the corresponding radical, which may dimerize to give isomeric bipyrans in the case of tpp + or a phenyl-phenyl or phenyl- pyranyl dimer in the case of thx+. The corresponding anions are the initial products of the second reduction step. The tpp - anion reacts with tpp + to give the bipyran while the thx- anions appear to undergo polymerization reactions with thx+. Both tpp + and thx+ and their reduction products are adsorbed at the mercury electrode. In the adsorbed state thx+ forms one of two surface phases depending on the potential, one with the molecules in a flat orientation and the other, a condensed phase, with vertically oriented molecules. Perchlorate ions are considered to be co-adsorbed with the cations. 
