NUCLEOPHILIC DISPLACEMENT-REACTIONS AT BENZYL HALIDE SELF-ASSEMBLED MONOLAYER FILM SURFACES

Surface chemical reactions at self-assembled monolayer (SAM) films con taining benzyl halide functional groups have been investigated. The be nzyl halide SAM films were chemisorbed onto silicon or silicon dioxide substrates. Nucleophilic substitution at the benzyl chloride group, e mploying NaI, results in exchange of chlorine for iodine. The rate for surface halogen exchange was compared to the rate in solution by H-1 NMR kinetics on a model compound. The rates and yields for reactions i n which the benzyl halide is converted to ethylenediamine or 3-pyridin e groups were studied by UV absorption spectroscopy and X-ray photoele ctron spectroscopy. The utility of the benzyl halide SAM films as surf ace-imaging resists and the importance of the surface modifications in a lithographic process employing ligand-based selective metalization are also discussed.