Operando Studies of Palladium-Catalysed Cross-Coupling Surface Chemistry

Pd-catalysed cross-coupling reactions represent key technologies employed within academia and industry, however the fine chemicals sector urgently needs new catalytic systems for large-scale, continuous processing. This proposal underpins the development of alternative, heterogeneous Pd-catalysed processes to meet this demand. Commercialization of such catalytic clean technologies awaits detailed knowledge of their optimal formulation and associated reaction conditions. This information in turn requires insight into both the mechanisms of such surface reactions and their associated deactivation pathways in order to control both activity and selectivity (homo- versus cross-coupling). Here we propose to obtain microscopic-level understanding of Heck and Suzuki-Miyaura chemistry over well-defined model palladium surfaces through the use of operando surface spectroscopies and mechanistic reaction probes. We have recently pioneered the application of in-situ, X-ray photoelectron spectroscopy for real-time investigations of industrially significant, surface catalysed processes including alkyne trimerisation, C-H activation and VOC destruction. These methodologies will also allow us to determine whether heterogeneously catalysed cross-coupling shares common reaction intermediates and rate-limiting steps with its more conventional homogeneous counterparts. The intellectual output from this project will be invaluable in designing a new toolbox of high performance dispersed Pd catalysts that will revolutionise organic synthetic chemistry.