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Published on: January 8, 2016
γ-Agostic interactions in (MesCCC)Fe-Mes(L) complexes
Daniel C Najera1, Marconi N Peñas-Defrutos2,3, Max García-Melchor2
1School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, Illinois 61801, USA. fout@illinois.edu.
Abstract:
Agostic interactions were observed in the bound mesityl group in a series of iron compounds bearing a bis(NHC) pincer CCC ligand. The L-type ligand on [(CCC)FeIIMes(L)] complexes influences the strength of the agostic interaction and is manifested in the upfield shift of the 1H NMR resonance for the mesityl methyl resonances. The nature of the interaction was further investigated by density functional theory calculations, allowing rationalization of some unexpected trends and proving to be a powerful predictive tool.
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