TY  - INPR
A1  - Stennett, Tom
A1  - Mattock, James
A1  - Vollert, Ivonne
A1  - Vargas, Alfredo
A1  - Braunschweig, Holger
T1  - Unsymmetrical, Cyclic Diborenes and Thermal Rearrangement to a Borylborylene
T2  - Angewandte Chemie, International Edition
N2  - Cyclic diboranes(4) based on a chelating monoanionic, benzylphosphine linker were prepared by boron-silicon exchange between arylsilanes and B\(_2\)Br\(_4\). Coordination of Lewis bases to the remaining sp\(^2\) boron atom yielded unsymmetrical sp\(^3\)-sp\(^3\) diboranes, which were reduced with KC\(_8\) to their corresponding trans-diborenes. These compounds were studied by a combination of spectroscopic methods, X-ray diffraction and DFT calculations. PMe\(_3\)-stabilized diborene 6 was found to undergo thermal rearrangement to gem- diborene 8. DFT calculations on 8 reveal a polar boron-boron bond, and indicate that the compound is best described as a borylborylene.
KW  - boron
KW  - borylene
KW  - multiple bonds
KW  - rearrangement
KW  - DFT calculations
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160258
N1  - This is the pre-peer reviewed version of the following article: T. E. Stennett, J. D. Mattock, I. Vollert, A. Vargas, H. Braunschweig, Angew. Chem. Int. Ed. 2018, 57, 4098., which has been published in final form at DOI: 10.1002/anie.201800671. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
VL  - 57
ER  - 
TY  - JOUR
A1  - Brückner, Tobias
A1  - Heß, Merlin
A1  - Stennett, Tom E.
A1  - Rempel, Anna
A1  - Braunschweig, Holger
T1  - Synthesis of Boron Analogues of Enamines via Hydroamination of a Boron-Boron Triple Bond
BT  - Dedicated to Professor Wolfgang Kaim on the occasion of his 70th birthday
JF  - Angewandte Chemie, International Edition
N2  - An N-heterocyclic-carbene-stabilized diboryne undergoes rapid, high-yielding and catalyst-free hydroamina- tion reactions with primary amines, yielding 1-amino-2-hydro- diborenes, which can be considered boron analogues of enamines. The electronics of the organic substituent at nitrogen influence the structure and further reactivity of the diborene product. With electron-rich anilines, a second hydroamination can occur at the diborene to generate 1,1-diamino-2,2-dihy- drodiboranes. With isopropylamine, the electronic influence of the alkyl substituent upon the diborene leads to an unprece- dented boron-mediated intramolecular N-dearylation reaction of an N-heterocyclic carbene unit.
KW  - boron
KW  - diborynes
KW  - diborenes
KW  - DFT
KW  - enamines
KW  - hydroamination
KW  - multiple bonds
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-240669
VL  - 60
IS  - 2
ER  -