TY  - JOUR
A1  - Thiess, Torsten
A1  - Ernst, Moritz
A1  - Kupfer, Thomas
A1  - Braunschweig, Holger
T1  - Facile Access to Substituted 1,4‐Diaza‐2,3‐Diborinines
JF  - Chemistry – A European Journal
N2  - 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.
KW  - azadiboretidines
KW  - B,N-heterocycles
KW  - diazadiborinines
KW  - diboranes
KW  - ring expansion
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214650
VL  - 26
IS  - 13
SP  - 2967
EP  - 2972
ER  - 
TY  - INPR
A1  - Braunschweig, Holger
A1  - Brückner, Tobias
A1  - Deißenberger, Andrea
A1  - Dewhurst, Rian
A1  - Gackstatter, Annika
A1  - Gärtner, Annalena
A1  - Hofmann, Alexander
A1  - Kupfer, Thomas
A1  - Prieschl, Dominic
A1  - Thiess, Torsten
A1  - Wang, Sunewang Rixin
T1  - Reaction of Dihalodiboranes(4) with N-Heterocyclic Silylenes: Facile Construction of 1-Aryl-2-Silyl-1,2-Diboraindanes
T2  - Chemistry, A European Journal
N2  - Dihalodiboranes(4) react with an N-heterocyclic silylene (NHSi) to generate NHSi-adducts of 1-aryl-2-silyl-1,2-diboraindanes as confirmed by X-ray crystallography, featuring the functionalization of both B–X (X = halogen) bonds and a C–H bond under mild conditions. Coordination of a third NHSi to the proposed 1,1-diaryl- 2,2-disilyldiborane(4) intermediates, generated by a two-fold B–X insertion, may be crucial for the C–H borylation that leads to the final products. Notably, our results demonstrate the first C–H borylation with a strong B–F bond activated by silylene insertion.
KW  - diborane
KW  - boron
KW  - silylenes
KW  - CH activation
KW  - bond activation
KW  - diboraindanes
KW  - diboranes
KW  - synthetic methods
KW  - borylation
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-153068
N1  - This is the pre-peer reviewed version of the following article: H. Braunschweig, T. Brückner, A. Deißenberger, R. D. Dewhurst, A. Gackstatter, A. Gärtner, A. Hofmann, T. Kupfer, D. Prieschl, T. Thiess, S. R. Wang, Reaction of Dihalodiboranes(4) with a N-Heterocyclic Silylene: Facile Construction of 1-Aryl-2-Silyl-1,2-Diboraindanes, Chem. Eur. J. 2017, 23, 9491., which has been published in final form at dx.doi.org/10.1002/chem.201702377. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving
ER  -