Selective coupling of oxygenates is critical to many synthetic processes, including those necessary for the development of alternative fuels. We report a general process for selective coupling of aldehydes and methanol as a route to ester synthesis. All steps are mediated by oxygen-covered metallic gold nanoparticles on Au (111). Remarkably, cross-coupling of methanol with formaldehyde, acetaldehyde, benzaldehyde and benzeneacetaldehyde to ...