TY - JOUR A1 - Föhrenbacher, Steffen A. A1 - Zeh, Vivien A1 - Krahfuss, Mirjam J. A1 - Ignat'ev, Nikolai V. A1 - Finze, Maik A1 - Radius, Udo T1 - Tris(pentafluoroethyl)difluorophosphorane and N‐Heterocyclic Carbenes: Adduct Formation and Frustrated Lewis Pair Reactivity JF - European Journal of Inorganic Chemistry N2 - The synthesis and characterization of Lewis acid/base adducts between tris(pentafluoroethyl)difluorophosphorane PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) and selected N-heterocyclic carbenes (NHCs) R\(_{2}\)Im (1,3-di-organyl-imidazolin-2-ylidene) and phosphines are reported. For NHCs with small alkyl substituents at nitrogen (R=Me, nPr, iPr) the adducts NHC ⋅ PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) (2 a–h) were isolated. The reaction with the sterically more demanding NHCs Dipp\(_{2}\)Im (1,3-bis-(2,6-di-iso-propylphenyl)-imidazolin-2-ylidene) (1 i) and tBu\(_{2}\)Im (1,3-di-tert-butyl-imidazolin-2-ylidene) (1 j) afforded the aNHC adducts 3 i and 3 j (a denotes “abnormal” NHC coordination via a backbone carbon atom). The use of tBuMeIm (1-tert-butyl-3-methyl-imidazolin-2-ylidene) (1 m) led to partial decomposition of the NHC and formation of the salt [tBuMeIm−H][MeIm ⋅ PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\)] (4 m). The phosphorane PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) forms adducts with PMe\(_{3}\) but does not react with PPh\(_{3}\) or PCy\(_{3}\). The mer-cis isomer of literature-known Me\(_{3}\)P ⋅ PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) (5 a) was structurally characterized. Mixtures of the phosphorane PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) and the sterically encumbered NHCs tBu\(_{2}\)Im, Dipp\(_{2}\)Im, and Dipp\(_{2}\)Im\(^{H2}\) (1,3-bis-(2,6-di-iso-propylphenyl)-imidazolidin-2-ylidene) (1 k) showed properties of FLPs (Frustrated Lewis Pairs) as these mixtures were able to open the ring of THF (tetrahydrofuran) to yield NHC−(CH\(_{2}\))\(_{4}\)O−PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\) 6 i–k. Furthermore, the deprotonation of the weak C−H acids CH\(_{3}\)CN, acetone, and ethyl acetate was achieved, which led to the formation of the corresponding imidazolium salts and the phosphates [PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\)(CH\(_{2}\)CN)]\(^{-}\) (7), [PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\)(OC(=CH\(_{2}\))CH\(_{3}\))]\(^{-}\) (8) and [PF\(_{2}\)(C\(_{2}\)F\(_{5}\))\(_{3}\)(CH\(_{2}\)CO\(_{2}\)Et)]\(^{-}\) (9). KW - C-H activation KW - N-Heterocyclic Carbene Adducts KW - N-Heterocyclic Carbenes KW - Frustrated Lewis Pairs KW - Fluoro(perfluoroalkyl) phosphoranes Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257386 VL - 2021 IS - 20 ER - TY - THES A1 - Föhrenbacher, Steffen Albert T1 - Tris(pentafluorethyl)difluorphosphoran als \(Lewis\)-saure Komponente von Frustrierten \(Lewis\)-Paaren und als Fluorid-Akzeptor in der Übergangsmetallchemie T1 - Tris(pentafluoroethyl)difluorophosphorane as \(Lewis\) acidic component of Frustrated \(Lewis\) Pairs and as fluoride acceptor in transition metal chemistry N2 - Im Rahmen dieser Arbeit wurde die Reaktivität des Phosphorans (C2F5)3PF2 gegenüber Lewis-Basen (N-heterozyklische Carbene und Phosphane) und gegenüber verschiedenen Übergangsmetall-Fluoridokomplexen untersucht. Im ersten Teil werden die Lewis-Säure/Base-Addukte zwischen (C2F5)3PF2 und verschiedenen N-heterozyklischen Carbenen (NHCs) beschrieben. Der Fokus des zweiten Teils der Arbeit liegt auf der Darstellung kationischer Komplexe ausgehend von neutralen d-Block-Metallfluoriden, welche durch Fluorid-Transfer auf das Lewis-acide (C2F5)3PF2 erfolgt. Hierbei wurden Komplexe verschiedener Übergangsmetalle (Ti, Ni, Cu) verwendet, wodurch der Fluorid-Transfer auf das Phosphoran quer über die 3d-Reihe untersucht wurde. Im letzten Kapitel dieser Arbeit wurden die Synthese und die Anwendung von Kationen des Typs [(NHC)Cu]+ eingehender untersucht. Dazu wurde zunächst die Synthese der Ausgangsverbindungen [(NHC)Cu(F)] modifiziert. Anschließend wurden diese Fluorido-Komplexe auf deren Reaktivität gegenüber (C2F5)3PF2 untersucht. Nachfolgend wurden die Reaktivität von [(Dipp2Im)Cu(C6Me6)]FAP in Ligandenaustauschreaktionen bzw. die Synthese von Komplexen [(Dipp2Im)Cu(LB)]FAP (LB = Lewis-Base) eingehender untersucht. N2 - In the course of this work, the reactivity of the phosphorane (C2F5)3PF2 towards Lewis bases (N-heterocyclic carbenes and phosphines) and various transition-metal fluorido complexes was investigated. In the first part, Lewis acid/base adducts of (C2F5)3PF2 and several N-heterocyclic carbenes (NHCs) are described. The focus of the second part of the work is on the synthesis of cationic complexes starting from neutral d-block metal fluorides, which takes place via fluoride transfer to the Lewis acidic (C2F5)3PF2. Complexes of several transition metals (Ti, Ni, Cu) were applied, whereby the fluoride transfer to the phosphorane was investigated across the 3d row. In the last part of this work the synthesis and application of cations of the type [(NHC)Cu]+ were examined in more detail. First, the synthesis of the starting materials [(NHC)Cu(F)] was modified. Subsequently the reactivity of these fluorido complexes towards (C2F5)3PF2 was investigated. The reactivity of [(Dipp2Im)Cu(C6Me6)]FAP in ligand exchange reactions and the synthesis of complexes [(Dipp2Im)Cu(LB)]FAP (LB = Lewis base) was subsequently studied in more detail. KW - Phosphorane KW - Übergangsmetallkomplexe KW - Addukt KW - Kupfer KW - N-heterozyklische Carbene KW - Frustrierte Lewis-Paare KW - Schwach koordinierende Anionen KW - Fluor(perfluoralkyl)phosphorane KW - N-Heterocyclic Carbenes KW - Frustrated Lewis Pairs KW - Fluoro(perfluoroalkyl)phosphoranes KW - Weakly Coordinating Anions Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-251602 ER -