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Two-coordinate Fe⁰ and Co⁰ complexes supported by cyclic (alkyl)(amino)carbenes
Gaël Ung1, Jonathan Rittle, Michele Soleilhavoup
1Division of Chemistry and Chemical Engineering, California Institute of Technology (USA).
Abstract:
The CAAC [CAAC=cyclic (alkyl)(amino)carbene] family of carbene ligands have shown promise in stabilizing unusually low-coordination number transition-metal complexes in low formal oxidation states. Here we extend this narrative by demonstrating their utility in affording access to the first examples of two-coordinate formal Fe(0) and Co(0) [(CAAC)2M] complexes, prepared by reduction of their corresponding two-coordinate cationic Fe(I) and Co(I) precursors. The stability of these species arises from the strong σ-donating and π-accepting properties of the supporting CAAC ligands, in addition to steric protection.
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