Dative Bonding between Group 13 Elements Using a Boron‐Centered Lewis Base

Abstract

An electron-rich monovalent boron compound is used as a Lewis base to prepare adducts with Group 13 Lewis acids using both its boron and nitrogen sites. The hard Lewis acid AlCl3 binds through a nitrogen atom of the Lewis base, while softer Lewis acids GaX3 (Cl, Br, I) bind at the boron atom. The latter are the first noncluster Lewis adducts between a boron-centered Lewis base and a main-group Lewis acid.

Boranchemie aus einer neuen Perspektive: Nukleophilie der B‐H‐Bindungselektronen

“…[22] Einige Jahre später konnte diese Beobachtung durch Studien von Burg und Schlesinger bestätigt werden. (8)]. (7)],w ährend mit NH 3 ein Produkt (DADB) mit der Summenformel B 2 H 6 ·2 NH 3 isoliert werden konnte [Gl.…”

“…Ein weiterer Reaktionspfad von grundlegender Bedeutung im Zusammenhang mit der Lewis-Aziditätv on BH 3 ist die Hydroborierung. Hierzu zählt die Einführung sterisch abschirmender Donorliganden (Abbildung 2) und die direkte Umwandlung der nicht fassbaren Nukleophile in stabile Hauptgruppenelementderivate [7,8] bzw. Das unbesetzte 2p-Orbital am BH 3 -Boratom ist anschließend in der Lage,mit den C = C-, C = O-oder C = N-Doppelbindungen bzw.d en CC-Dreifachbindungen der Substrate zu interagieren, wodurch ein erster Hydroborierungskomplex gebildet wird.…”

Easy access to nucleophilic boron through diborane to magnesium boryl metathesis

“…Although a rich and varied chemistry has since arisen from the reactivity of compound 1 and related N- heterocyclic boryl anions with organic914, transition metal15161718 and main group electrophiles1419202122232425, alternative nucleophilic boron reagents remain very rare species262728293031. Notable exceptions are Braunschweig's dimetalloborylene and borolyl anions (for example, 2 and 3 )3233 Bertrand and Kinjo's carbene-stabilised monovalent boron species (for example, 4 )3435363738 and a remarkable tricyanoborandiyl dianion394041. Although the transient generation of {BH 2 } − anion equivalents has also been achieved within the coordination sphere of 1,3-bis-(2,6-diisopropyl-phenyl)imidazol-2-ylidene42, the syntheses of all these species require strongly reducing and potentially problematic reaction conditions (for example, Li metal or C 8 K) to achieve the formal B(I) oxidation state.…”

From Borane to Borylene without Reduction: Ambiphilic Behavior of a Monovalent Silylisonitrile Boron Species

“…[10] Unsymmetrical diboranes(4) [11] and diboranes (5), such as V, [12] also show much promise as easily accessible sources of one nucleophilic boron moiety.Circumventing reduction, Hill and co-workers synthesized the magnesium-bound boryl anion (VI)b yf acile s-bond metathesis. [13] In reports related to this work, the groups of Finze and Bertrand showed that multiple electron-withdrawing cyano substituents at anionic or neutral hydroboron species cause aB ÀHb ond umpolung, which enables deprotonation to dianion VII [14] or the cAACstabilized boryl anion VIII.…”