Executive Summary : | Water microdroplets can act as superacids, stabilizing carbocations that can enhance their lifetimes by over six orders of magnitude. This superacidic nature can be used to develop a new arena of microdroplet catalysis for conducting chemical reactions that are difficult to conduct in bulk-phase conditions. Preliminary studies suggest that aryl carbocations can be spontaneously generated in superacidic water microdroplets from phenol precursors. This proposal aims to investigate the mechanism of this transformation in microdroplet catalysis and use this to open a new gate of aromatic substitution (SN1) reaction in microdroplets. The hypothesize that electrohydrodynamically generated water droplets can provide enough stability to aryl carbocations, allowing their combination with various nucleophiles to yield substituted aromatic compounds, including O18-labelled phenols. The project will involve customizing microdroplet generating sources, examining the stability and mechanism of their formation, and utilizing the synthetic application of aryl carbocations in microdroplets to establish a synthetic strategy without the need for metals, ligands, or harsh reaction conditions. This new discovery will contribute to the understanding of microdroplet catalysis and help in invoking a paradigm of unusual chemical transformation in microdroplets. |