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Updated: May 8, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Normal-to-abnormal rearrangement and NHC activation in three-coordinate iron(II) carbene complexes
Benjamin M Day1, Thomas Pugh, Daniël Hendriks
1School of Chemistry, The University of Manchester , Manchester, M13 9PL, U.K.
Abstract:
The 'normal' three-coordinate iron-NHC complex [(IPr)Fe(N'')2] (N″ = N(SiMe3)2) rearranges to its abnormal NHC analogue [(aIPr)Fe(N″)2] (6) on heating, providing a rare abnormal iron-aNHC complex, and the first such three-coordinate complex. The tert-butyl-substituted complex [(I(t)Bu)Fe(N″)2] (4) undergoes a thermal decomposition that has not previously been observed in iron-NHC chemistry, resulting in the bis(imidazole) complex [((t)BuIm)2Fe(N″)2] (7). A mechanism that involves consecutive C-H and C-N activation is proposed to account for the formation of 7.
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