Azidoborolate anions and azidoborole adducts: isolable forms of an unstable borole azide. Issue 30 (24th March 2022)

• Record Type: Journal Article
• Authors: Lindl, Felix; Fantuzzi, Felipe; Mailänder, Lisa; Hörl, Christian; Bélanger-Chabot, Guillaume; Braunschweig, Holger
• Is Part Of: Chemical communications. Volume 58:Issue 30(2022)
• Page Start: 4735
• Page End: 4738
• Publication Date: 2022-03-24
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1039/d2cc00543c
• Languages: English
• ISSNs: 1359-7345

Abstract

Abstract : An unstable azidoborole derivative was prepared and indirectly identified through trapping in the form of neutral Lewis adducts and, quite surprisingly, in the form of the diazidoborolate complex anion. 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.