TY  - INPR
A1  - Arrowsmith, Merle
A1  - Mattock, James D.
A1  - Böhnke, Julian
A1  - Krummenacher, Ivo
A1  - Vargas, Alfredo
A1  - Braunschweig, Holger
T1  - Direct access to a cAAC-supported dihydrodiborene and its dianion
T2  - Chemical Communications
N2  - The two-fold reduction of (cAAC)BHX\(_2\) (cAAC = 1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene; X = Cl, Br) provides a facile, high-yielding route to the dihydrodiborene (cAAC)\(_2\)B\(_2\)H\(_2\). The (chloro)hydroboryl anion reduction intermediate was successfully isolated using a crown ether. Overreduction of the diborene to its dianion [(cAAC)\(_2\)B\(_2\)H\(_2\)]\(^{2−}\) causes a decrease in the B–B bond order whereas the B–C bond orders increase.
KW  - carbenes
KW  - diborenes
KW  - boron
KW  - main-group chemistry
KW  - diborynes
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164276
N1  - This is the pre-peer reviewed version of the following article: Chemical Communications, 2018, 54, 4669-4672 which has been published at DOI: 10.1039/C8CC01580E
ER  - 
TY  - INPR
A1  - Hermann, Alexander
A1  - Cid, Jessica
A1  - Mattock, James D.
A1  - Dewhurst, Rian D.
A1  - Krummenacher, Ivo
A1  - Vargas, Alfredo
A1  - Ingleson, Michael J.
A1  - Braunschweig, Holger
T1  - Diboryldiborenes: π‐Conjugated B\(_4\) Chains Isoelectronic to the Butadiene Dication
T2  - Angewandte Chemie, International Edition
N2  - sp\(^2\)–sp\(^3\) diborane species based on bis(catecholato)diboron and N-heterocyclic carbenes (NHCs) are subjected to catechol/bromide exchange selectively at the sp\(^3\) boron atom. The reduction of the resulting 1,1-dibromodiborane adducts led to reductive coupling and isolation of doubly NHC-stabilized 1,2-diboryldiborenes. These compounds are the first examples of molecules exhibiting pelectron delocalization over an all-boron chain.
KW  - diboranes
KW  - diborenes
KW  - N-heterocyclic carbenes
KW  - boron chains
KW  - pi-conjugation
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167977
N1  - This is the pre-peer reviewed version of the following article: A. Hermann, J. Cid, J. D. Mattock, R. D. Dewhurst, I. Krummenacher, A. Vargas, M. J. Ingleson, H. Braunschweig, Angew. Chem. Int. Ed. 2018, 57, 10091, which has been published in final form at https://doi.org/10.1002/anie.201805394. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
ER  - 
TY  - INPR
A1  - Muessig, Jonas H.
A1  - Thaler, Melanie
A1  - Dewhurst, Rian D.
A1  - Paprocki, Valerie
A1  - Seufert, Jens
A1  - Mattock, James D.
A1  - Vargas, Alfredo
A1  - Braunschweig, Holger
T1  - Phosphine-Stabilized Diiododiborenes: Isolable Diborenes with Six Labile Bonds
T2  - Angewandte Chemie, International Edition
N2  - The lability of B=B, B-P and B-halide bonds is combined in the syntheses of the first diiododiborenes. In a series of reactivity tests, these diiododiborenes demonstrate cleavage of all six of their central bonds in different ways, leading to products of B=B hydrogenation and dihalogenation as well as halide exchange.
KW  - boron
KW  - low-valent main-group species
KW  - iodine
KW  - multiple bonding
KW  - 1,2-additions
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178608
N1  - This is the pre-peer reviewed version of the following article: J. H. Muessig, M. Thaler, R. D. Dewhurst, V. Paprocki, J. Seufert, J. D. Mattock, A. Vargas, H. Braunschweig, Angew. Chem. Int. Ed. 2019, 58, 4405, which has been published in final form at https://doi.org/10.1002/anie.201814230. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
ER  - 
TY  - INPR
A1  - Wang, Sunewang R.
A1  - Arrowsmith, Merle
A1  - Böhnke, Julian
A1  - Braunschweig, Holger
A1  - Dellermann, Theresa
A1  - Dewhurst, Rian D.
A1  - Kelch, Hauke
A1  - Krummenacher, Ivo
A1  - Mattock, James D.
A1  - Müssig, Jonas H.
A1  - Thiess, Torsten
A1  - Vargas, Alfredo
A1  - Zhang, Jiji
T1  - Engineering a Small HOMO-LUMO Gap and Intramolecular B–B Hydroarylation by Diborene/Anthracene Orbital Intercalation
T2  - Angewandte Chemie, International Edition
N2  - The diborene 1 was synthesized by reduction of a mixture of 1,2-di-9-anthryl-1,2-dibromodiborane(4) (6) and trimethylphosphine with potassium graphite. The X-ray structure of 1 shows the two anthryl rings to be parallel and their π(C\(_{14}\)) systems perpendicular to the diborene π(B=B) system. This twisted conformation allows for intercalation of the relatively high-lying π(B=B) orbital and the low-lying π* orbital of the anthryl moiety with no significant conjugation, resulting in a small HOMO-LUMO gap (HLG) and ultimately an unprecedented anthryl B–B bond hydroarylation. The HLG of 1 was estimated to be 1.57 eV from the onset of the long wavelength band in its UV–vis absorption spectrum (THF, λ\(_{onset}\) = 788 nm). The oxidation of 1 with elemental selenium afforded diboraselenirane 8 in quantitative yield. By oxidative abstraction of one phosphine ligand by another equivalent of elemental selenium, the B–B and C\(^1\)–H bonds of 8 were cleaved to give the cyclic 1,9-diboraanthracene 9.
KW  - boron
KW  - small HOMO-LUMO gap
KW  - diborenes
KW  - borylation
KW  - hydroarylation
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-148126
N1  - This is the pre-peer reviewed version of the following article: S. R. Wang, M. Arrowsmith, J. Böhnke, H. Braunschweig, T. Dellermann, R. D. Dewhurst, H. Kelch, I. Krummenacher, J. D. Mattock, J. H. Müssig, T. Thiess, A. Vargas, J. Zhang, Angew. Chem. Int. Ed. 2017, 56, 8009., which has been published in final form at DOI: 10.1002/anie.201704063. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
VL  - 56
IS  - 27
ER  -