Imidyl and nitrene metal species play an important role in the -functionalisation of unreactive C-H bonds as well as the aziridination of olefines. We report on the synthesis of the trigonal imido iron complexes [Fe(NMes)L] (L = -N{Dipp}SiMe); Dipp = 2,6-diisopropyl-phenyl; Mes = (2,4,6-trimethylphenyl) reaction of mesityl azide (MesN) with the linear iron precursors [FeL]. UV-vis-, EPR-, Fe Mössbauer spectroscopy, magnetometry, and computational methods suggest for the reduced form an electronic structure as a ferromagnetically coupled iron(ii) imidyl radical, whereas oxidation leads to mixed iron(iii) imidyl and electrophilic iron(ii) nitrene character. Reactivity studies show that both complexes are capable of H atom abstraction from C-H bonds. Further, the reduced form [Fe(NMes)L] reacts nucleophilically with CS by inserting into the imido iron bond, as well as electrophilically with CO under nitrene transfer. The neutral [Fe(NMes)L] complex shows enhanced electrophilic behavior as evidenced by nitrene transfer to a phosphine, yet in combination with an overall reduced reactivity.
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