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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Isolation of a labile homoleptic diazenium cation
Wolfgang Baumann1, Dirk Michalik, Fabian Reiß
1Universität Rostock, Institut für Chemie, Albert-Einstein-Strasse 3a, 18059 Rostock (Deutschland) http://www.chemie.uni-rostock.de/ac/schulz; Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse 29a, 18059 Rostock (Germany).
Abstract:
Following our interest in nitrogen chemistry, we now describe the synthesis, structure, and bonding of labile disilylated diazene, its GaCl3 adduct, and the intriguing trisilylated diazenium ion [(Me3 Si)2 NN-SiMe3 ](+), a dark blue and highly labile (Tdecomp >-30 °C) homoleptic cation of the type [R3 N2 ](+). Although direct silylation of Me3 Si-N=N-SiMe3 failed, the [(Me3 Si)2 N=N-SiMe3](+) ion was generated in a straightforward two-electron oxidation reaction from mercury(II) dihydrazide and Ag[GaCl4]. Moreover, previous structure data of Me3 Si-NN-SiMe3 were revised on the basis of new data.
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