Halide-coupled double electron transfer with electron-rich diboranes

• Verfasst von: Filbeck, Erik [VerfasserIn]
• Verfasst von: Cremer, Sebastian [VerfasserIn]
• Verfasst von: Jansen, Moritz C. F. [VerfasserIn]
• Verfasst von: Kaifer, Elisabeth [VerfasserIn]
• Verfasst von: Himmel, Hans-Jörg [VerfasserIn]
• Titel: Halide-coupled double electron transfer with electron-rich diboranes
• Verf.angabe: Erik Filbeck, Sebastian Cremer, Moritz C.F. Jansen, Elisabeth Kaifer, and Hans-Jörg Himmel
• E-Jahr: 2023
• Jahr: 20 September 2023
• Umfang: 8 S.
• Fussnoten: Gesehen am 29.11.2023
• Titel Quelle: Enthalten in: Chemistry - a European journal
• Ort Quelle: Weinheim : Wiley-VCH, 1995
• Jahr Quelle: 2023
• Band/Heft Quelle: (2023), Artikel-ID e202302911, Seite 1-8
• ISSN Quelle: 1521-3765
• DOI: doi:10.1002/chem.202302911
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: B−B bond cleavage
• Sach-SW: boron
• Sach-SW: diborane
• Sach-SW: electron transfer
• Sach-SW: reduction
• K10plus-PPN: 1871575990

Abstract

The ditriflato-diborane B2(μ-hpp)2(OTf)2 (hpp=1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate) acts as a stable surrogate of the elusive dication [B2(hpp)2]2+, being both electrophilic (vacant boron p orbitals) and nucleophilic (filled B−B bond orbital). This combination of seemingly contrasting behaviors could be used to develop a metallomimetic diborane chemistry, with Lewis σ-basic and π-acidic substrates being bound and reduced at the diborane. Here, we report on a novel reaction type within this general theme, in which double electron transfer from the diboron unit to the boron-bound organic substrate is coupled with halide transfer in the other direction. Novel diborylated dienamines are synthesized in this way. The scope of this unprecedented reaction motif and the reaction pathways are elucidated.