Reversible binding of resorcin[4]arene cavitands onto a self-assembled monolayer

The association of tetra(thio)urea recorcin[ 4]arenes dissolved in acetone with a chloride-containing monolayer on gold has been investigated. The ass embling process appears to be driven by the selective molecular recognition of halide ions at the self-assembled surface by the cavitands. It is shown that the layers formed are stable in ethylacetate and acetone, and can be desorbed by hydrochloric acid in ethanol (pH similar to 1). In the case of thiourea-containing compounds, adsorption is partially irreversible, possib ly as a result of defect sites in the monolayer. (C) 1999 Elsevier Science B.V. AU rights reserved.