Synthesis and characterization of isocyano-based monolayers as potential dual-function electric field probes.

Abstract

Electric field catalysis is an up-and-coming subfield of chemistry. The method most tunable for a wider range of reactions is the oriented external electric field method, which relies on an external potentiostat to generate an electric field along a catalyst or reactant for a reaction of interest. To fully harness and calculate the generated local electric field, self-assembled monolayers (SAMs) with a probe molecule, such as an isocyanide or carbonyl functional group, have been employed on gold electrodes to anchor a catalyst. This project aimed to study the packing orientation of 1,n-diisocyanoalkane monolayers and to introduce 1-mercaptoalkyl isocyanides as an alternative monolayer. Water contact angles were measured and support a previous finding that 1,n-diisocyanoalkane monolayers form looped structures. However, sum frequency generation spectra and cyclic voltammetry experiments contradicted this claim, suggesting that unbound -NC groups are present. Therefore, 1,n-diisocyanoalkane monolayers may potentially serve as suitable dual electric field probes and tethering groups for orientationcontrolled catalysis.