Using Triazabutadienes as a Protected Source of Diazonium Cations to Facilitate Electrografting to a Variety of Conductive Surfaces

Aryl diazonium electrografting is a versatile methodology for the functionalization of electrode surfaces, yet its usage has been hampered by both the short lifespan of aryl diazonium cations in aqueous solution and the harsh conditions required to generate them in situ. This can make accessing complicated aryl diazonium cations and derivatized surfaces thereof difficult. The usage of triazabutadienes has the potential to address many of these issues as triazabutadienes are stable enough to endure multiple-step chemical syntheses and can persist for several hours in aqueous solution, yet upon UV exposure rapidly release aryl diazonium cations under mild conditions (i.e., 0 °C, pH 7 aqueous solution). Herein is described the synthesis and utilization of a versatile, highly water-soluble triazabutadiene scaffold which can be used to access complicated aryl diazonium cations (via photochemical decaging with a commercially available 365 nm UV irradiation source), which themselves can be used to directly derivatize electrode surfaces with desired organic moieties.