New π-Extended 1,1′-Disubstituted Ferrocenes with Thioate and Dithioate End Groups

Abstract

Extended π systems based on 1,1′-aryl or (2-arylethynyl) disubstitution at ferrocene with thioate or dithioate end groups are reported. In the context of molecular electronics, such end groups are possible alternative end groups for the attachment of molecular wires at gold surfaces. The respective thioates were successfully prepared in high yields via the respective carboxylic acid derivatives. Subsequent treatment with Lawesson's reagent led to the respective dithioates. However, this did not work in the presence of triple bonds, in these cases, product mixtures were formed. On the basis of literature evidence with Woollin's reagent, the selenium analog of Lawesson's reagent, one product was tentatively characterized as a double cyclization product of two triple bonds and two molecules of Lawesson's reagent. Preliminary experiments towards the formation of gold complexes by reaction with a Johnphos gold(I) salt are included.