Über die Chemie des [Me3Si]+ - Ions

Im Rahmen dieser Arbeit wurde eine Reihe von Trityl-Verbindungen als Präkursoren für die Darstellung entsprechender TMS-Salze untersucht. Die synthetisierten TMS-Präkursoren konnten erfolgreich für die Synthese von persilylierten Sulfat-, Phosphat- und Sulfid-Ionen genutzt werden. Ferner konnte das Verhalten der neutralen silylierten Spezies gegenüber Basen untersucht werden. Die Chemie entspricht somit weitestgehend der der protonierten Mineralsäuren. Bisher schwer zugängliche Wasserstoffsäuren wie HNSO & HPCO konnten auf eine neue und einfache Weise synthetisiert und charakterisiert werden.Within the scope of this work, a series of new trityl compounds was investigated as precursors for the synthesis of corresponding TMS salts. The synthesized TMS precursors were successfully used for the preparation of persilylated sulfate, phosphate and sulfide cations. It was possible to investigate the behavior against bases and therefore generate mono-/bissilylated anionic species. Thus, this chemistry largely corresponds to that of the protonated acids. Hydrogen acids hitherto difficult to access, such as HNSO & HPCO, could be synthesized and characterized with a new synthetic procedure

HPCO - A phosphorus-containing analogue of isocyanic acid

We describe the isolation and spectroscopic characterization of the heavier phosphorus‐containing analogue of isocyanic acid (HPCO), and its isotopologue (DPCO). This fundamental small molecule, which has been postulated to exist in interstellar space, has thus far only been observed at low gas phase concentrations or in inert gas matrices. In this report we describe its synthesis, spectroscopic properties, and reactivity in solution

Synthesis of the First Persilylated Ammonium Ion, [(Me₃Si)₃NSi(H)Me₂]⁺, by Silylium-Catalyzed Methyl/Hydrogen Exchange Reactions

This work describes the unexpected synthesis and characterization of the first persilylated ammonium ion, [(Me₃Si)₃NSi­(H)­Me₂]⁺, in the reaction of (Me₃Si)₃N with [Me₃Si–H–SiMe₃]­[B­(C₆F₅)₄]. NMR and Raman studies revealed a transition-metal-free silylium ion catalyzed substituent redistribution process when [Me₃Si–H–SiMe₃]⁺ was used as the silylating reagent. These observations were affirmed in the reaction with [Et₃Si–H–SiEt₃]­[B­(C₆F₅)₄]. A Lewis acid catalyzed scrambling process always occurs if an excess of silanes is present in the formation of silylium cations while employing the standard Bartlett–Schneider–Condon type reaction. Additionally, the thermodynamics of this process was accessed by DFT computations at the pbe1pbe/aug-cc-pVDZ level, indicating alkyl substituent exchange equilibria at the silane and preference of the formation of [(Me₃Si)₃NSi­(H)­Me₂]⁺ over [(Me₃Si)₄N]⁺

HPCO-A Phosphorus-Containing Analogue of Isocyanic Acid

We describe the isolation and spectroscopic characterization of the heavier phosphorus‐containing analogue of isocyanic acid (HPCO), and its isotopologue (DPCO). This fundamental small molecule, which has been postulated to exist in interstellar space, has thus far only been observed at low gas phase concentrations or in inert gas matrices. In this report we describe its synthesis, spectroscopic properties, and reactivity in solution

Synthesis of the First Persilylated Ammonium Ion, [(Me₃Si)₃NSi(H)Me₂]⁺, by Silylium-Catalyzed Methyl/Hydrogen Exchange Reactions

This work describes the unexpected synthesis and characterization of the first persilylated ammonium ion, [(Me₃Si)₃NSi­(H)­Me₂]⁺, in the reaction of (Me₃Si)₃N with [Me₃Si–H–SiMe₃]­[B­(C₆F₅)₄]. NMR and Raman studies revealed a transition-metal-free silylium ion catalyzed substituent redistribution process when [Me₃Si–H–SiMe₃]⁺ was used as the silylating reagent. These observations were affirmed in the reaction with [Et₃Si–H–SiEt₃]­[B­(C₆F₅)₄]. A Lewis acid catalyzed scrambling process always occurs if an excess of silanes is present in the formation of silylium cations while employing the standard Bartlett–Schneider–Condon type reaction. Additionally, the thermodynamics of this process was accessed by DFT computations at the pbe1pbe/aug-cc-pVDZ level, indicating alkyl substituent exchange equilibria at the silane and preference of the formation of [(Me₃Si)₃NSi­(H)­Me₂]⁺ over [(Me₃Si)₄N]⁺