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    On Silylated Oxonium and Sulfonium Ions and Their Interaction with Weakly Coordinating Borate Anions
    (Weinheim : Wiley-VCH, 2019) Bläsing, Kevin; Labbow, Rene; Michalik, Dirk; Reiß, Fabian; Schul, Axel; Villinger, Alexander; Walker, Svenja
    Attempts have been made to prepare salts with the labile tris(trimethylsilyl)chalconium ions, [(Me3Si)3E]+ (E=O, S), by reacting [Me3Si-H-SiMe3][B(C6F5)4] and Me3Si[CB] (CB−=carborate=[CHB11H5Cl6]−, [CHB11Cl11]−) with Me3Si-E-SiMe3. In the reaction of Me3Si-O-SiMe3 with [Me3Si-H-SiMe3][B(C6F5)4], a ligand exchange was observed in the [Me3Si-H-SiMe3]+ cation leading to the surprising formation of the persilylated [(Me3Si)2(Me2(H)Si)O]+ oxonium ion in a formal [Me2(H)Si]+ instead of the desired [Me3Si]+ transfer reaction. In contrast, the expected homoleptic persilylated [(Me3Si)3S]+ ion was formed and isolated as [B(C6F5)4]− and [CB]− salt, when Me3Si-S-SiMe3 was treated with either [Me3Si-H-SiMe3][B(C6F5)4] or Me3Si[CB]. However, the addition of Me3Si[CB] to Me3Si-O-SiMe3 unexpectedly led to the release of Me4Si with simultaneous formation of a cyclic dioxonium dication of the type [Me3Si-μO-SiMe2]2[CB]2 in an anion-mediated reaction. DFT studies on structure, bonding and thermodynamics of the [(Me3Si)3E]+ and [(Me3Si)2(Me2(H)Si)E]+ ion formation are presented as well as mechanistic investigations on the template-driven transformation of the [(Me3Si)3E]+ ion into a cyclic dichalconium dication [Me3Si-μE-SiMe2]22+. © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
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    Salts of HCN-Cyanide Aggregates : [CN(HCN)2]− and [CN(HCN)3]−
    (Weinheim : Wiley-VCH, 2020) Bläsing, Kevin; Harloff, Jörg; Schulz, Axel; Stoffers, Alrik; Stoer, Philip; Villinger, Alexander
    Although pure hydrogen cyanide can spontaneously polymerize or even explode, when initiated by small amounts of bases (e.g. CN−), the reaction of liquid HCN with [WCC]CN (WCC=weakly coordinating cation=Ph4P, Ph3PNPPh3=PNP) was investigated. Depending on the cation, it was possible to extract salts containing the formal dihydrogen tricyanide [CN(HCN)2]− and trihydrogen tetracyanide ions [CN(HCN)3]− from liquid HCN when a fast crystallization was carried out at low temperatures. X-ray structure elucidation revealed hydrogen-bridged linear [CN(HCN)2]− and Y-shaped [CN(HCN)3]− molecular ions in the crystal. Both anions can be considered members of highly labile cyanide-HCN solvates of the type [CN(HCN)n]− (n=1, 2, 3 …) as well as formal polypseudohalide ions. © 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
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    Trimethylsilyl Pseudohalide Adducts of GaCl3 and B(C6F5)3
    (Weinheim : Wiley-VCH, 2021) Bläsing, Kevin; Bresien, Jonas; Maurer, Steffen; Schulz, Axel; Villinger, Alexander
    Me3Si−X (X=CN, N3, OCN, and SCN) was treated with the Lewis acids GaCl3 and B(C6F5)3 in toluene yielding the desired adducts Me3Si−X→GaCl3 and Me3Si−X→B(C6F5)3. All synthesized adducts were isolated and completely characterized including single crystal structure elucidations. The different structures, thermodynamics of formation and charge transfer effects are discussed on the basis of experimental and theoretical data.