TY  - JOUR
A1  - Hagspiel, Stephan
A1  - Arrowsmith, Merle
A1  - Fantuzzi, Felipe
A1  - Vargas, Alfredo
A1  - Rempel, Anna
A1  - Hermann, Alexander
A1  - Brückner, Tobias
A1  - Braunschweig, Holger
T1  - Highly colored boron-doped thiazolothiazoles from the reductive dimerization of boron isothiocyanates
JF  - Angewandte Chemie International Edition
N2  - Reduction of (CAAC)BBr\(_2\)(NCS) (CAAC=cyclic alkyl(amino)carbene) in the presence of a Lewis base L yields tricoordinate (CAAC)LB(NCS) borylenes which undergo reversible E/Z-isomerization. The same reduction in the absence of L yields deep blue, bis(CAAC)-stabilized, boron-doped, aromatic thiazolothiazoles resulting from the dimerization of dicoordinate (CAAC)B(NCS) borylene intermediates.
KW  - inorganic chemistry
KW  - aromaticity
KW  - reduction
KW  - fused thiazaboroles
KW  - DFT
KW  - borylenes
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256432
VL  - 60
IS  - 12
ER  - 
TY  - JOUR
A1  - Ewing, William C.
A1  - Dellermann, Theresa
A1  - Angel Wong, Y. T.
A1  - Mattock, James D.
A1  - Vargas, Alfredo
A1  - Bryce, David L.
A1  - Dewhurst, Rian D.
A1  - Braunschweig, Holger
T1  - \(\pi\)‐Complexes of Diborynes with Main Group Atoms
JF  - Chemistry – An Asian Journal
N2  - We present herein an in‐depth study of complexes in which a molecule containing a boron‐boron triple bond is bound to tellurate cations. The analysis allows the description of these salts as true π complexes between the B−B triple bond and the tellurium center. These complexes thus extend the well‐known Dewar‐Chatt‐Duncanson model of bonding to compounds made up solely of p block elements. Structural, spectroscopic and computational evidence is offered to argue that a set of recently reported heterocycles consisting of phenyltellurium cations complexed to diborynes bear all the hallmarks of \(\pi\)‐complexes in the \(\pi\)‐complex/metallacycle continuum envisioned by Joseph Chatt. Described as such, these compounds are unique in representing the extreme of a metal‐free continuum with conventional unsaturated three‐membered rings (cyclopropenes, azirenes, borirenes) occupying the opposite end.
KW  - boron
KW  - main group elements
KW  - solid-state NMR
KW  - \(\pi\) interactions
KW  - multiple bonds
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214677
VL  - 15
IS  - 10
SP  - 1553
EP  - 1557
ER  - 
TY  - JOUR
A1  - Schmidt, Uwe
A1  - Werner, Luis
A1  - Arrowsmith, Merle
A1  - Deissenberger, Andrea
A1  - Hermann, Alexander
A1  - Hofmann, Alexander
A1  - Ullrich, Stefan
A1  - Mattock, James D.
A1  - Vargas, Alfredo
A1  - Braunschweig, Holger
T1  - trans-Selective Insertional Dihydroboration of a cis-Diborene: Synthesis of Linear sp\(^3\)-sp\(^2\)-sp\(^3\)-Triboranes and Subsequent Cationization
JF  - Angewandte Chemie International Edition
N2  - The reaction of aryl‐ and amino(dihydro)boranes with dibora[2]ferrocenophane 1 leads to the formation 1,3‐trans ‐dihydrotriboranes by formal hydrogenation and insertion of a borylene unit into the B=B bond. The aryltriborane derivatives undergo reversible photoisomerization to the cis ‐1,2‐μ‐H‐3‐hydrotriboranes, while hydride abstraction affords cationic triboranes, which represent the first doubly base‐stabilized B3H4\(^+\) analogues.
KW  - cations
KW  - hydroboration
KW  - photoisomerization
KW  - triboranes
KW  - diborenes
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-208090
VL  - 59
IS  - 1
ER  - 
TY  - JOUR
A1  - Braunschweig, Holger
A1  - Ewing, William C.
A1  - Ghosh, Sundargopal
A1  - Kramer, Thomas
A1  - Mattock, James D.
A1  - Östreicher, Sebastian
A1  - Vargas, Alfredo
A1  - Werner, Christine
T1  - Trimetallaborides as starting points for the syntheses of large metal-rich molecular borides and clusters
JF  - Chemical Science
N2  - Treatment of an anionic dimanganaborylene complex ([{Cp(CO)\(_2\)Mn}\(_2\)B]\(^-\)) with coinage metal cations stabilized by a very weakly coordinating Lewis base (SMe\(_2\)) led to the coordination of the incoming metal and subsequent displacement of dimethylsulfide in the formation of hexametalladiborides featuring planar four-membered M\(_2\)B\(_2\) cores (M = Cu, Au) comparable to transition metal clusters constructed around four-membered rings composed solely of coinage metals. The analogies between compounds consisting of B\(_2\)M\(_2\) units and M\(_4\) (M = Cu, Au) units speak to the often overlooked metalloid nature of boron. Treatment of one of these compounds (M = Cu) with a Lewis-basic metal fragment (Pt(PCy\(_3\))\(_2\)) led to the formation of a tetrametallaboride featuring two manganese, one copper and one platinum atom, all bound to boron in a geometry not yet seen for this kind of compound. Computational examination suggests that this geometry is the result of d\(^{10}\)-d\(^{10}\) dispersion interactions between the copper and platinum fragments.
KW  - anionic dimetalloborylene complexes
KW  - trimetallaborides
KW  - tetrametallaborides
KW  - Boron
KW  - metallaboranes
KW  - crystal structure
KW  - metal borylene complexes
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191511
VL  - 7
IS  - 1
ER  - 
TY  - JOUR
A1  - Braunschweig, Holger
A1  - Krummenacher, Ivo
A1  - Mailänder, Lisa
A1  - Pentecost, Leanne
A1  - Vargas, Alfredo
T1  - Formation of a stable radical by oxidation of a tetraorganoborate
JF  - Chemical Communications
N2  - Herein, we describe the selective formation of a stable neutral spiroborate radical by one-electron oxidation of the corresponding tetraorganoborate salt Li[B(C\(_4\)Ph\(_4\))\(_2\)], formally containing a tetrahedral borate centre and a s-cis-butadiene radical cation as the spin-bearing site. Spectroscopic and computational methods have been used to determine the spin distribution and the chromism observed in the solid state.
KW  - tetraorganoborate salt
KW  - spiroborates
KW  - one-electron oxidation
KW  - spin distribution
KW  - chromism
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191321
VL  - 52
IS  - 43
ER  - 
TY  - JOUR
A1  - Braunschweig, Holger
A1  - Constantinidis, Philipp
A1  - Dellermann, Theresa
A1  - Ewing, William
A1  - Fischer, Ingo
A1  - Hess, Merlin
A1  - Knight, Fergus
A1  - Rempel, Anna
A1  - Schneider, Christoph
A1  - Ullrich, Stefan
A1  - Vargas, Alfredo
A1  - Woolins, Derek
T1  - Highly Strained Heterocycles Constructed from Boron–Boron Multiple Bonds and Heavy Chalcogens
JF  - Angewandte Chemie, International Edition
N2  - The reactions of a diborene with elemental selenium or tellurium are shown to afford a diboraselenirane or diboratellurirane, respectively. These reactions are reminiscent of the sequestration of subvalent oxygen and nitrogen in the formation of oxiranes and aziridines; however, such reactivity is not known between alkenes and the heavy chalcogens. Although carbon is too electronegative to affect the reduction of elements with lower relative electronegativity, the highly reducing nature of the B B double bond enables reactions with Se0 and Te0. The capacity of multiple bonds between boron atoms to donate electron density is highlighted in reactions where diborynes behave as nucleophiles, attacking one of the two Te atoms of diaryltellurides, forming salts consisting of diboratellurenium cations and aryltelluride anions.
KW  - Boron
KW  - Heterocycles
KW  - Multiple bonds
KW  - Selenium
KW  - Tellurium
KW  - Bor
KW  - Heterocyclische Verbindungen
KW  - Selen
KW  - Tellur
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138237
N1  - This is the peer reviewed version of the following article: Angew. Chem. Int. Ed. 2016, 55, 5606–5609, which has been published in final form at 10.1002/anie.201601691. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
N1  - Accepted Version
VL  - 55
IS  - 18
SP  - 5606
EP  - 5609
ER  -