2,6-DITHIENYL-SUBSTITUTED PYRYLIUM-SALTS AS PRECURSORS OF FUNCTIONALIZED LANGMUIR FILMS

Starting from 2,6-dithienyl pyrylium perchlorates, the pyrylation reac tion was used to obtain 2,6-dithienyl-4-arylpyrylium salts. These salt s yield stable monolayers at the air-water interface. Multilayers can be easily built up and films free of light scattering defects were obt ained, Both the solution and the Langmuir-Blodgett films exposed to io dine vapor seem to lead to a molecular complex while, on treatment wit h FeCl3, oxidation and formation of oligothiophenes have been detected .