BN‐Phenanthryne: Cyclotetramerization of an 1,2‐Azaborine Derivative

Abstract

Thermolysis of 9-azido-9-borafluorene in heptane solution produces the tetramer of a BN-phenanthryne. The isolation of the self-trapping product provides evidence for the involvement of the BN-aryne in the thermolysis reaction. Its formation may be rationalized by denitrogenation of the azide and ring enlargement.

1,2‐Azaborine: The Boron‐Nitrogen Derivative of ortho‐Benzyne

“…[4] However, evidence for the existence of BN-arynes is scarce and indirect as it comes from a self-trapping experiment. [5] Here we show by direct spectroscopic techniques that 1,2-azaborine can exist as reactive intermediate. We found that 1 can be generated by flash vacuum pyrolysis (FVP) from precursor 2 by thermal elimination of tert -butyldimethylsilylchloride and isolated in cryogenic matrices.…”

“…[3, 5] This can be rationalized by the difference in electronegativity: the more electronegative N atom prefers to have a lone pair (HOMO-1) in plane while the more electropositive B atom prefers an empty in-plane orbital (LUMO) that has strong p-character (Figure 3a). The natural bond orbital (NBO) analysis arrives at occupancies of 1.80 e − and 0.22 e − for the lone pair and empty orbitals, respectively, and a pronounced n(N) → n*(B) interaction (E(2) = 27.6 kcal/mol) according to the second-order perturbation estimate of donor-acceptor interaction in the NBO basis.…”

Reactivity of a coordinated inorganic acetylene unit, HBNH, and the azidoborane cation [HB(N3)]+

“…It is salient to mention that the generation of transient nitrenes from boron azides is known in the literature. 1a,16 …”

Band‐Gap Engineering of Graphene Heterostructures by Substitutional Doping with B3N3

“…Recent studies reported the synthesis of such in‐plane heterosheets of graphene and h‐BN . Furthermore, nanoscale graphene flakes containing a B 3 N 3 ring (B 3 N 3 : borazine) have been chemically synthesized, indicating the possibility of BNC heterosheets in which the B 3 N 3 is periodically implemented in a honeycomb network of C . By analogy with porous graphene or graphene nanomeshes, B 3 N 3 ‐doped graphene is a promising candidate for a semiconducting graphene material whose band gap can be tuned by controlling the mutual arrangement of B 3 N 3 in graphitic network.…”