Shaping A Transition-metal coordination sphere to Unveil Routes uNmet in catalysis: main-group cations and iron triad metals (Fe, Co, Ni) as a starting kit

Objective

Transition-metal (TM) catalysis is pivotal in organic synthesis, and led to spectacular breakthroughs in that field over the last fifty years. In particular, development of catalysts using non-noble metals from the iron triad (Fe, Co, Ni) keeps attracting a lot of efforts. This is due not only to their low cost and their abundance, but also to their incredibly diverse reactivity, thanks to a broad panel of oxidation states and coordination patterns. Still, the design of efficient Fe, Co or Ni catalysts proves to be tedious work, as their coordination sphere often requires drastic rearrangements along the reaction paths. To accommodate those events, next-generation catalysts have to display a high plasticity, and must overcome the paradigms of classic design of static ligand spheres, with no consideration of their dynamic evolution. The central idea of the SATURN project is to use external main-group Lewis acids to achieve a dynamic control of the composition of the TM coordination sphere, with a focus on Fe, Co and Ni chemistry. In a catalytic context, this original approach will i) unlock the formation of key intermediates and ii) drive their reactivity towards selective paths, providing new strategies in synthetic chemistry. The first work package (WP1) will establish the general guidelines of this approach, and show that main-group Lewis acids can modulate the coordination sphere of reactive TM compounds. Development of new catalytic 3-component couplings will validate this approach. To widen the application scope of this method, WP2 will enable the control of a single TM catalyst by different main-group Lewis acids, whose nature will selectively guide the system towards different EH functionalization paths (E = C, Si, B, Ge). The last WP3 will show that this approach can also modulate the reactivity of redox-active catalysts, achieving a control of both TM and main-group oxidation states, leading to new strategies of alkyne difunctionalization.