A Highly Reactive Geminal P/B Frustrated Lewis Pair: Expanding the Scope to C−X (X=Cl,Br) Bond Activation |
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| Authors: | Kamil Samigullin Isabelle Georg Dr Michael Bolte Dr Hans‐Wolfram Lerner Prof Dr Matthias Wagner |
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| Affiliation: | 1. Institut für Anorganische und Analytische Chemie, Goethe-Universit?t Frankfurt, Frankfurt am Main, Germany;2. +49)?69‐798‐29260 |
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| Abstract: | The geminal frustrated Lewis pair tBu2PCH2B(Fxyl)2 ( 1 ; Fxyl=3,5‐(CF3)2C6H3) is accessible in 65 % yield from tBu2PCH2Li and (Fxyl)2BF. According to NMR spectroscopy and X‐ray crystallography, 1 is monomeric both in solution and in the solid state. The intramolecular P ??? B distance of 2.900(5) Å and the full planarity of the borane site exclude any significant P/B interaction. Compound 1 readily activates a broad variety of substrates including H2, EtMe2SiH, CO2/CS2, Ph2CO, and H3CCN. Terminal alkynes react with heterolysis of the C?H bond. Haloboranes give cyclic adducts with strong P?BX3 and weak R3B?X bonds. Unprecedented transformations leading to zwitterionic XP/BCX3 adducts occur on treatment of 1 with CCl4 or CBr4 in Et2O. In less polar solvents (C6H6, n‐pentane), XP/BCX3 adduct formation is accompanied by the generation of significant amounts of XP/BX adducts. FLP 1 catalyzes the hydrogenation of PhCH=NtBu and the hydrosilylation of Ph2CO with EtMe2SiH. |
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| Keywords: | boron carbon– halogen activation frustrated Lewis pairs phosphorus trihalomethanides |
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