Aryl Migration on Graphene.

The design and synthesis of molecular systems able to carry out movements resembling macroscopic objects is an exciting and challenging endeavor. Molecules that can walk covalently on a track have been demonstrated, and we now report how aryl groups that can migrate over a graphene surface. Specifically, we describe a system comprised of covalently functionalized aryl groups on graphene that undergo continuous aryl shifts. The dynamic aryl shift allows the aryl groups on graphene to effectively migrate step-by-step wherein each step involves reversible bond breaking and making that is initiated by a combination of an activated arene and p-doping of the graphene surface. Raman spectroscopic mapping of the distribution of the covalent attachment revealed that activated 4-methoxyphenyl groups migrate several microns from regions of high functionalization to regions with no prior functionalization.