Metal ion recognition and molecular templating in self-assembled monolayers of cyclic and acyclic polyethers

摘要

Our recent work with cyclic and acyclic polyetherself-assembled monolayers (SAMs) on gold is presented. A seriesof dithia-crown-tetrathiafulvalene derivatives with one or twodisulfide groups has been prepared, and their SAMs on gold have beencharacterized by electrochemistry and by reflection–absorptioninfrared spectroscopy. These SAMs are extremely stable on repeatedelectrochemical potential scans and can selectively recognize alkalimetal ions. Acyclic polyether derivatives can also self-assemble ongold to yield selective metal ion recognition domains. Impedancespectroscopy data for these SAMs fit the Langmuir isotherm and allowthe determination of ion association constants. Some of the SAMsprepared with new acyclic polyether derivatives are able to detectpotassium cations selectively when templated in their presence. Thesestructures are believed to be a consequence of ion “imprinting”during the process of SAM formation.