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Double donation in trigonal planar iron-carbodiphosphorane complexes - a concise study on their spectroscopic and
Nis-Julian H Kneusels1, Jörn E Münzer1, Kimon Flosdorf1
1Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany. istemi.kuzu@chemie.uni-marburg.de frenking@chemie.uni-marburg.de.
Abstract:
We present the syntheses of trigonal planar coordinated Fe(ii) carbodiphosphorane (CDPR) complexes, starting from iron(ii)-bis(trimethylsilylamide) [Fe{N(SiMe3)2}2] and hexaphenyl-(CDPPh) and sym-dimethyltetraphenyl-carbodiphosphoranes (CDPMe), respectively. Both complexes [CDPPh-Fe{N(SiMe3)2}2] (1) and [CDPMe-Fe{N(SiMe3)2}2] (2) were examined in solution and in the solid state. 1 shows a dissociation equilibrium in solution which we monitored by variable temperature 1H-NMR spectroscopy. Magnetic measurements of 1 and 2 yielded a high spin configuration (S = 2) for both complexes. Quantum chemical calculations were performed to analyze the bonding situation in compound 1.
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