Access to Metal Centers and Fluxional Hydride Coordination Integral for CO₂ Insertion into [Fe₃(μ-H)₃]³⁺ Clusters.

ABSTRACT: CO₂ insertion into tri(μ-hydrido)triiron(II) clusters ligated by a tris(β-diketiminate) cyclophane is demonstrated to be balanced by sterics for CO₂ approach and hydride accessibility. Time-resolved NMR and UV-vis spectra for this reaction for a complex in which methoxy groups border the pocket of the hydride donor (Fe₃H₃L², 4) result in a decreased activation barrier and increased kinetic isotope effect consistent with the reduced sterics. For the ethyl congener Fe₃H₃L¹ (2), no correlation is found between rate and reaction solvent or added Lewis acids, implying CO₂ coordination to an Fe center in the mechanism. The estimated hydricity (50 kcal/mol)

SUBMITTER: Hong DH 

PROVIDER: S-EPMC8247455 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature