Ullmann Coupling Reactions on Gold Nanoparticles

There has been a plethora of experience in conducting organic reactions in solution, with little to no knowledge in organic reactions on surfaces. Broadening the horizon of organic on-surface synthesis will enable creation of functional materials and direct integration into devices. Herein, we report an Ullmann reaction on thiol-functionalized gold nanoparticles serving as reactant, stabilizing agent, catalyst and reducing agent in this transformation. The orientation of ligands and formation of Surface Assembled Monolayer (SAM) on the gold nanoparticles were exploited to attain selectivity of hetero- over homo-Ullmann coupling, thus, expanding the toolbox of organic on-surface synthesis to nanoparticles.