CO to Isonitrile Substitution in Iron Cyclopentadienone Complexes: A Class of Active Iron Catalysts for Borrowing Hydrogen Strategies

Discovering active, cheap iron complexes for eco-compatible borrowing hydrogen transformations constitutes a real challenge. In this context, we developed a family of isonitrile-substituted iron cyclopentadienone complexes. They were successfully applied in traditional borrowing hydrogen amine alkylation with alcohols and, notably, in the development of a photoactivated multicatalytic enantioselective allylic alcohol functionalization. Of importance, the catalyst showing greater activity under photoirradiation differs from the one most active in conventional amine alkylation using chemical activation. This underscores the importance of incorporating isonitrile ligands in a readily customizable manner, resulting in active catalysts with complementary reactivities. The characterization of their physical properties was complemented by density functional theory calculations to enhance our understanding of their behavior. Given the distinctive properties of the disclosed iron catalysts, their application is poised to pave the way for exploring challenging reactivities in related catalytic processes.