@unpublished{ArrowsmithBoehnkeBraunschweigetal.2017,
  author    = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Celik, Mehmet Ali},
  title     = {Reactivity of a Dihydrodiborene with CO: Coordination, Insertion, Cleavage and Spontaneous Cyclic Alkyne Formation},
  series = {Angewandte Chemie, International Edition},
  journal   = {Angewandte Chemie, International Edition},
  doi       = {10.1002/anie.201707907},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-153318},
  year      = {2017},
  abstract  = {Under a CO atmosphere the dihydrodiborene [(cAAC)HB=BH(cAAC)] underwent coordination of CO concomitant with reversible hydrogen migration from boron to the carbene carbon atom, as well as reversible CO insertion into the B=B bond. Heating of the CO-adduct resulted in two unusual cAAC ring-expansion products, one presenting a B=C bond to a six-membered 1,2-azaborinane-3-ylidene, the other an unprecedented nine-membered cyclic alkyne resulting from reductive cleavage of CO and spontaneous C≡C triple bond formation.},
  language  = {en}
}
@article{ThiessErnstKupferetal.2020,
  author    = {Thiess, Torsten and Ernst, Moritz and Kupfer, Thomas and Braunschweig, Holger},
  title     = {Facile Access to Substituted 1,4-Diaza-2,3-Diborinines},
  series = {Chemistry - A European Journal},
  volume    = {26},
  journal   = {Chemistry - A European Journal},
  number    = {13},
  doi       = {10.1002/chem.201905356},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214650},
  pages     = {2967 -- 2972},
  year      = {2020},
  abstract  = {Several bis(dimethylamino)-substituted 1,4-diaza-2,3-diborinines (DADBs) were synthesized with variable substituents at the backbone nitrogen atoms. By reaction with HCl or BX\(_{3}\) (X=Br, I), these species were successfully converted into their synthetically more useful halide congeners. The high versatility of the generated B-X bonds in further functionalization reactions at the boron centers was demonstrated by means of salt elimination (MeLi) and commutation (NMe\(_{2}\) DADBs) reactions, thus making the DADB system a general structural motif in diborane(4) chemistry. A total of 18 DADB derivatives were characterized in the solid state by X-ray diffraction, revealing a strong dependence of the heterocyclic bonding parameters from the exocyclic substitution pattern at boron. According to our experiments towards the realization of a Dipp-substituted, sterically encumbered DADB, the mechanism of DADB formation proceeds via a transient four-membered azadiboretidine intermediate that subsequently undergoes ring expansion to afford the six-membered DADB heterocycle.},
  language  = {en}
}