title: Redox-Active N-Heterocyclic Germylenes and Stannylenes with a Ferrocene-1,1'-diyl Backbone.
abstract: We describe ferrocene-based N-heterocyclic germylenes and stannylenes of the type [Fe{(η5-C5H4)NR}2E:] (1 RE; E=Ge, Sn; R=neopentyl (Np), mesityl (Mes), trimethylsilyl (TMS)), which constitute the first examples of redox-functionalised N-heterocyclic tetrylenes (NHTs). These compounds are thermally stable and were structurally characterised by means of X-ray diffraction studies, except for the neopentyl-substituted stannylene 1 NpSn, the decomposition of which afforded the aminoiminoferrocene [fc(NHCH2tBu)(N=CHtBu)] (2) and the spiro tin(IV) compound (1 Np)2Sn (3). DFT calculations show that the HOMO of the NHTs of our study is localised on the ferrocenylene backbone. A one-electron oxidation process affords ions of the type 1 RE+.. In contrast to the NHC system 1 RC, the localised ferrocenium-type nature of the oxidised form does not compromise the fundamental tetrylene character of 1 RE+..
authors.affiliation: Institute of Chemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132, Kassel, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Oetzel
authors.affiliation: Institute of Chemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132, Kassel, Germany.
authors.forename: Nadine
authors.initials: N
authors.lastname: Weyer
authors.affiliation: Institute of Chemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132, Kassel, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Bruhn
authors.affiliation: Institute of Chemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132, Kassel, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Leibold
authors.affiliation: Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstrasse 30, 48149, Münster, Germany.
authors.forename: Birgit
authors.initials: B
authors.lastname: Gerke
authors.affiliation: Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstrasse 30, 48149, Münster, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Pöttgen
authors.affiliation: Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78453, Konstanz, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Maier
authors.affiliation: Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78453, Konstanz, Germany.
authors.forename: Rainer F
authors.initials: RF
authors.lastname: Winter
authors.affiliation: Institut für Anorganisch und Analytische Chemie, Johann Wolfgang Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438, Frankfurt am Main, Germany.
authors.forename: Max C
authors.initials: MC
authors.lastname: Holthausen
authors.affiliation: Institute of Chemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132, Kassel, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Siemeling
keywords: cyclic voltammetry; germanium; iron; metallocenes; tin