Facile insertion of a cyclic alkyl(amino) carbene carbon into the B–B bond of diboron(4) reagents

Abstract

We report herein the room temperature insertion of the carbene carbon atom of the cyclic (alkyl)(amino) carbene cAAC into the B-B single bonds of the diboron(4) compounds Bpin, Bcat, Bneop, and Beg (pin = pinacolato, cat = catecholato, neop = neopentylglycolato, eg = ethyleneglycolato).

Selective Boryl‐Anion Migration in a Vinyl sp2−sp3 Diborane Induced by Soft Borane Lewis Acids

“…[11][12][13][14][15][16][17] We hypothesised that an alternative route to induce intramolecular 1,2-boryl-anion migration would be the activation of an unsaturated R À group (e.g. [11][12][13][14][15][16][17] We hypothesised that an alternative route to induce intramolecular 1,2-boryl-anion migration would be the activation of an unsaturated R À group (e.g.…”

Recent Advances in the Domain of Cyclic (Alkyl)(Amino) Carbenes

“…[138] Insertion of carbene carbon into BÀ B bonds have been reported by different research groups and a couple of reviews have also been published on this subject. [139][140][141] Most recently, Radius and co-workers [142] have reported the insertion of carbene carbon of cAAC into the BÀ B bond of different diboron compounds (Scheme 32). To demonstrate the insertion, cAAC Me (74) was reacted with different diboron compounds including B 2 Pin 2 , B 2 Cat 2 , B 2 neop 2, and B 2 eg 2 at room temperature.…”

“…This irreversible insertion reaction is a convenient method for the preparation of C1-bridged bisborates with a quaternary carbon atom. [142] Braunschweig et al have extensively explored the cAAC chemistry of boron which they have summarized in a review. [143] Their recent work includes the isolation of compounds containing diboron flanked by two cAAC ligands (borylenes), which have been used in exotic chemical reactions.…”

Revealing the electronic properties of the B–B bond: the bis-catecholato diboron molecule

“…While being thermodynamically stable, 5 its Lewis acid character favors its activation upon interaction with bases. 4,6 The resulting adducts are precursors of the B-B bond cleavage for the formation of boron compounds [7][8][9][10][11] . Beside its employment in synthesis processes, due to this strong affinity with bases, the diboron(4) compounds may be of potential interest as building blocks in the 2D supramolecular assembly on surfaces as well.…”