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Updated: Sep 29, 2025
Synthesis of 1,2-Azaborines and the Preparation of Their Protein Complexes with T4 Lysozyme Mutants
Published on: March 25, 2017
Azidoborolate anions and azidoborole adducts: isolable forms of an unstable borole azide
Felix Lindl1,2, Felipe Fantuzzi3, Lisa Mailänder1,2
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. h.braunschweig@uni-wuerzburg.de.
Abstract:
Boroles are well known to undergo ring expansion reactions with organic azides to yield 1,2-azaborinines. A synthon featuring both azide and borole moieties within the same molecule, 1-azido-2,3,4,5-tetraphenylborole, was found to be much less stable than the related, previously-reported azidoborafluorene and decomposed to intractable mixtures well below room temperature. It could, however, be trapped at -75 °C through the formation of Lewis base adducts, even in the form of the "azide-stabilized azidoborole" complex anion diazidoborolate. DFT calculations provide a rationale for the low stability of the azidoborole under study.
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