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Updated: Nov 1, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Double α,α CH bond insertion into sp3 CH2 moiety: synthesis of a Fe carbene bis-hydride dinitrogen complex
Julien Petit1, Anthony Cavaillé1, Nathalie Saffon-Merceron2
1Laboratoire Hétérochimie Fondamentale et Appliquée, CNRS, France. mezailles@chimie.ups-tlse.fr.
Abstract:
Reduction of high spin paramagnetic complex [(κ2-P, P'-PCH2PCy)FeCl2] 2 by two electrons under N2 resulted in the formation of two isomeric low spin diamagnetic complexes 3trans and 3cis [Fe(κ3-P,C,P'-PCPCy)(H)2(N2)]. Cristallization allowed isolation of complex 3d [Fe(κ3-P,C,P'-PCPCy)(H)2]2(μ-N2), characterized by X-ray diffraction, Mössbauer and Raman spectroscopies. DFT calculations rationalized the facile double α,α CH bond insertion into a single sp3 CH2 moiety, as well as the fast exchange positions of the hydrides in the cis dihydride complex observed by NMR spectrocscopy.
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