Mono-, bis- and tetrahydroxy phthalocyanines as building blocks for monomolecular layer assemblies

We have developed three basic phthalocyanine structures, containing one, two, or four hydroxy groups, which are simple to synthesize and purify, as well as can be characterized well by NMR and MS. These building blocks can easily be further modified to have anchor groups, which make the molecules suitable for attachment to solid substrates. We have used thioacetate and pentafluorophenyl ester moieties, giving target phthalocyanines the ability to self-assemble on gold, metal oxides, and glass. Bonding densities calculated from the absorbances of the layers suggest mean molecular area to be in the range of 1-3 nm(2), which can be partially controlled by side substituents and the number of linkers.