Immobilization of π-conjugated molecules on Au using dendrimer-based templates

In this paper, we demonstrate immobilization of two kinds of π-conjugated molecules on Au using dendrimer-based templates; one is a p-phenylene ethynylene derivative and the other is a 4,4′-bis(phenylethynyl)-2,2′-bipyridine derivative. Both molecules were bound to benzyl-ether dendrons through an alkali-labile, ester linkage to give two different generation dendrimers. The removal of the dendrons from the self-assembled monolayers of the dendrimers left the isolated π-conjugated-molecules as well as small collections of the molecules on the surfaces, which was confirmed by surface Fourier transform infrared (FT-IR) spectroscopy and scanning tunneling microscopy (STM). Insertion of the dendrimer into n-dodecanethiol monolayer instead of the direct adsorption on a bare gold gave only the isolated, single molecules on the surface after the dendrons were removed.