@article{LiuLegareSeufertetal.2020,
  author    = {Liu, Siyuan and L{\´e}gar{\´e}, Marc-Andr{\´e} and Seufert, Jens and Prieschl, Dominic and Rempel, Anna and Englert, Lukas and Dellermann, Theresa and Paprocki, Valerie and Stoy, Andreas and Braunschweig, Holger},
  title     = {2,2′-Bipyridyl as a Redox-Active Borylene Abstraction Agent},
  series = {Inorganic Chemistry},
  volume    = {59},
  journal   = {Inorganic Chemistry},
  number    = {15},
  doi       = {10.1021/acs.inorgchem.0c01383},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-215595},
  pages     = {10866-10873},
  year      = {2020},
  abstract  = {2,2′-Bipyridyl is shown to spontaneously abstract a borylene fragment (R-B:) from various hypovalent boron compounds. This process is a redox reaction in which the bipyridine is reduced and becomes a dianionic substituent bound to boron through its two nitrogen atoms. Various transition metal-borylene complexes and diboranes, as a well as a diborene, take part in this reaction. In the latter case, our results show an intriguing example of the homolytic cleavage of a B═B double bond.},
  language  = {en}
}
@article{EwingDellermannAngelWongetal.2020,
  author    = {Ewing, William C. and Dellermann, Theresa and Angel Wong, Y. T. and Mattock, James D. and Vargas, Alfredo and Bryce, David L. and Dewhurst, Rian D. and Braunschweig, Holger},
  title     = {\(\pi\)-Complexes of Diborynes with Main Group Atoms},
  series = {Chemistry - An Asian Journal},
  volume    = {15},
  journal   = {Chemistry - An Asian Journal},
  number    = {10},
  doi       = {10.1002/asia.202000185},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214677},
  pages     = {1553 -- 1557},
  year      = {2020},
  abstract  = {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.},
  language  = {en}
}
@article{GoettelGaoDotzaueretal.2020,
  author    = {Goettel, James T. and Gao, Haopeng and Dotzauer, Simon and Braunschweig, Holger},
  title     = {\(^{Me}\)CAAC=N\(^{-}\): A Cyclic (Alkyl)(Amino)Carbene Imino Ligand},
  series = {Chemistry - A European Journal},
  volume    = {26},
  journal   = {Chemistry - A European Journal},
  number    = {5},
  doi       = {10.1002/chem.201904715},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212662},
  pages     = {1136-1143},
  year      = {2020},
  abstract  = {A cyclic (alkyl)(amino)carbene (CAAC) has been shown to react with a covalent azide similar to the Staudinger reaction. The reaction of \(^{Me}\)CAAC with trimethylsilyl azide afforded the N-silylated 2-iminopyrrolidine (\(^{Me}\)CAAC=NSiMe\(_{3}\)), which was fully characterized. This compound undergoes hydrolysis to afford the 2-iminopyrrolidine and trimethylsiloxane which co-crystallize as a hydrogen-bonded adduct. The N-silylated 2-iminopyrrolidine was used to transfer the novel pyrrolidine-2-iminato ligand onto both main-group and transition-metal centers. The reaction of the tetrabromodiborane bis(dimethyl sulfide) adduct with two equivalents of \(^{Me}\)CAAC=NSiMe\(_{3}\) afforded the disubstituted diborane. The reaction of \(^{Me}\)CAAC=NSiMe\(_{3}\) with TiCl\(_{4}\) and CpTiCl\(_{3}\) afforded \(^{Me}\)CAAC=NTiCl\(_{3}\) and \(^{Me}\)CAAC=NTiCl\(_{2}\)Cp, respectively.},
  language  = {en}
}
@article{RauchEndresFriedrichetal.2020,
  author    = {Rauch, Florian and Endres, Peter and Friedrich, Alexandra and Sieh, Daniel and H{\"a}hnel, Martin and Krummenacher, Ivo and Braunschweig, Holger and Finze, Maik and Ji, Lei and Marder, Todd B.},
  title     = {An Iterative Divergent Approach to Conjugated Starburst Borane Dendrimers},
  series = {Chemistry - A European Journal},
  volume    = {26},
  journal   = {Chemistry - A European Journal},
  number    = {57},
  doi       = {10.1002/chem.202001985},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218345},
  pages     = {12951 -- 12963},
  year      = {2020},
  abstract  = {Using a new divergent approach, conjugated triarylborane dendrimers were synthesized up to the 2nd generation. The synthetic strategy consists of three steps: 1) functionalization, via iridium catalyzed C-H borylation; 2) activation, via fluorination of the generated boronate ester with K[HF\(_{2}\)] or [N(nBu\(_{4}\))][HF\(_{2}\)]; and 3) expansion, via reaction of the trifluoroborate salts with aryl Grignard reagents. The concept was also shown to be viable for a convergent approach. All but one of the conjugated borane dendrimers exhibit multiple, distinct and reversible reduction potentials, making them potentially interesting materials for applications in molecular accumulators. Based on their photophysical properties, the 1st generation dendrimers exhibit good conjugation over the whole system. However, the conjugation does not increase further upon expansion to the 2nd generation, but the molar extinction coefficients increase linearly with the number of triarylborane subunits, suggesting a potential application as photonic antennas.},
  language  = {en}
}
@article{BruneckerMuessigArrowsmithetal.2020,
  author    = {Brunecker, Carina and M{\"u}ssig, Jonas H. and Arrowsmith, Merle and Fantuzzi, Felipe and Stoy, Andreas and B{\"o}hnke, Julian and Hofmann, Alexander and Bertermann, R{\"u}diger and Engels, Bernd and Braunschweig, Holger},
  title     = {Boranediyl- and Diborane(4)-1,2-diyl-Bridged Platinum A-Frame Complexes},
  series = {Chemistry - A European Journal},
  volume    = {26},
  journal   = {Chemistry - A European Journal},
  number    = {39},
  doi       = {10.1002/chem.202001168},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214707},
  pages     = {8518 -- 8523},
  year      = {2020},
  abstract  = {Diplatinum A-frame complexes with a bridging (di)boron unit in the apex position were synthesized in a single step by the double oxidative addition of dihalo(di)borane precursors at a bis(diphosphine)-bridged Pt\(^{0}\)\(_{2}\) complex. While structurally analogous to well-known μ-borylene complexes, in which delocalized dative three-center-two-electron M-B-M bonding prevails, theoretical investigations into the nature of Pt-B bonding in these A-frame complexes show them to be rare dimetalla(di)boranes displaying two electron-sharing Pt-B σ-bonds. This is experimentally reflected in the low kinetic stability of these compounds, which are prone to loss of the (di)boron bridgehead unit.},
  language  = {en}
}
@article{HuangWangDewhurstetal.2020,
  author    = {Huang, Zhenguo and Wang, Suning and Dewhurst, Rian D. and Ignat'ev, Nikolai V. and Finze, Maik and Braunschweig, Holger},
  title     = {Boron: Its Role in Energy-Related Processes and Applications},
  series = {Angewandte Chemie International Edition},
  volume    = {59},
  journal   = {Angewandte Chemie International Edition},
  number    = {23},
  doi       = {10.1002/anie.201911108},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218514},
  pages     = {8800 -- 8816},
  year      = {2020},
  abstract  = {Boron's unique position in the Periodic Table, that is, at the apex of the line separating metals and nonmetals, makes it highly versatile in chemical reactions and applications. Contemporary demand for renewable and clean energy as well as energy-efficient products has seen boron playing key roles in energy-related research, such as 1) activating and synthesizing energy-rich small molecules, 2) storing chemical and electrical energy, and 3) converting electrical energy into light. These applications are fundamentally associated with boron's unique characteristics, such as its electron-deficiency and the availability of an unoccupied p orbital, which allow the formation of a myriad of compounds with a wide range of chemical and physical properties. For example, boron's ability to achieve a full octet of electrons with four covalent bonds and a negative charge has led to the synthesis of a wide variety of borate anions of high chemical and electrochemical stability—in particular, weakly coordinating anions. This Review summarizes recent advances in the study of boron compounds for energy-related processes and applications.},
  language  = {en}
}
@article{SaalfrankFantuzziKupferetal.2020,
  author    = {Saalfrank, Christian and Fantuzzi, Felipe and Kupfer, Thomas and Ritschel, Benedikt and Hammond, Kai and Krummenacher, Ivo and Bertermann, R{\"u}diger and Wirthensohn, Raphael and Finze, Maik and Schmid, Paul and Engel, Volker and Engels, Bernd and Braunschweig, Holger},
  title     = {cAAC-stabilisierte 9,10-Diboraanthracene - offenschalige Singulettbiradikale},
  series = {Angewandte Chemie},
  volume    = {132},
  journal   = {Angewandte Chemie},
  number    = {43},
  doi       = {10.1002/ange.202008206},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218582},
  pages     = {19502 -- 19507},
  year      = {2020},
  abstract  = {Geringe HOMO-LUMO-Abst{\"a}nde und eine hohe Ladungstr{\"a}germobilit{\"a}t pr{\"a}destinieren die h{\"o}heren Acene f{\"u}r Anwendungen im Bereich der Organoelektronik. Die Leistungsf{\"a}higkeit derartiger Verbindungen steigt hierbei dramatisch mit der Anzahl anellierter Benzolringe. Gr{\"o}ßere Acenmengen sind synthetisch bisher jedoch nur f{\"u}r Acene bis Heptacen verl{\"a}sslich zug{\"a}nglich. Theoretischen Studien zufolge besitzen (Oligo)acene offenschalige Singulettbiradikal- und (Poly)acene polyradikalische Grundzust{\"a}nde. Eindeutige experimentelle Belege f{\"u}r diese Vorhersagen sind hingegen {\"a}ußerst selten. Durch den Einbau von zwei Boratomen in das Anthracengrundger{\"u}st konnten wir den HOMO-LUMO-Abstand von Acenen dramatisch verringern und zwar ohne die Notwendigkeit einer Ausweitung des konjugierten π-Systems. Stabilisierung der Borzentren durch cyclische (Alkyl)(amino)carbene lieferte hierbei neutrale 9,10-Diboraanthracene mit disjunkten, offenschaligen Singulettbiradikal-Grundzust{\"a}nden.},
  language  = {en}
}
@article{SaalfrankFantuzziKupferetal.2020,
  author    = {Saalfrank, Christian and Fantuzzi, Felipe and Kupfer, Thomas and Ritschel, Benedikt and Hammond, Kai and Krummenacher, Ivo and Bertermann, R{\"u}diger and Wirthensohn, Raphael and Finze, Maik and Schmid, Paul and Engel, Volker and Engels, Bernd and Braunschweig, Holger},
  title     = {cAAC-Stabilized 9,10-diboraanthracenes—Acenes with Open-Shell Singlet Biradical Ground States},
  series = {Angewandte Chemie International Edition},
  volume    = {59},
  journal   = {Angewandte Chemie International Edition},
  number    = {43},
  doi       = {10.1002/anie.202008206},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-217795},
  pages     = {19338 -- 19343},
  year      = {2020},
  abstract  = {Narrow HOMO-LUMO gaps and high charge-carrier mobilities make larger acenes potentially high-efficient materials for organic electronic applications. The performance of such molecules was shown to significantly increase with increasing number of fused benzene rings. Bulk quantities, however, can only be obtained reliably for acenes up to heptacene. Theoretically, (oligo)acenes and (poly)acenes are predicted to have open-shell singlet biradical and polyradical ground states, respectively, for which experimental evidence is still scarce. We have now been able to dramatically lower the HOMO-LUMO gap of acenes without the necessity of unfavorable elongation of their conjugated π system, by incorporating two boron atoms into the anthracene skeleton. Stabilizing the boron centers with cyclic (alkyl)(amino)carbenes gives neutral 9,10-diboraanthracenes, which are shown to feature disjointed, open-shell singlet biradical ground states.},
  language  = {en}
}
@article{MuessigLisinetskayaDewhurstetal.2020,
  author    = {Muessig, Jonas H. and Lisinetskaya, Polina and Dewhurst, Rian D. and Bertermann, R{\"u}diger and Thaler, Melanie and Mitric, Roland and Braunschweig, Holger},
  title     = {Dibortetraiodid (B\(_2\)I\(_4\)) ist im Festk{\"o}rper ein Polymer aus sp3-hybridisiertem Bor},
  series = {Angewandte Chemie},
  volume    = {132},
  journal   = {Angewandte Chemie},
  number    = {14},
  doi       = {10.1002/ange.201913590},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219653},
  pages     = {5574-5579},
  year      = {2020},
  abstract  = {Anhand der ersten Festk{\"o}rperstrukturen von Dibortetraiodid (B\(_2\)I\(_4\)) wird gezeigt, dass dieses nicht, wie lange angenommen, analog zu den leichteren Dibortetrahalogeniden B\(_2\)F\(_4\), B\(_2\)Cl\(_4\) und B\(_2\)Br\(_4\) in allen Aggregatzust{\"a}nden in Form diskreter Molek{\"u}le mit planaren, dreifach koordinierten Boratomen vorliegt. R{\"o}ntgenstrukturanalysen, Festk{\"o}rper-NMR- und IR-Messungen zeigen, dass B\(_2\)I\(_4\) im Festk{\"o}rper in zwei polymeren Konformeren vorkommt, die tetraedrisch koordinierte Boratome enthalten. Anhand von DFT-Rechnungen werden die IR-Spektren in L{\"o}sung und im Festk{\"o}rper simuliert und mit den experimentellen Daten verglichen.},
  language  = {de}
}
@article{PaprockiHrobarikHarrimanetal.2020,
  author    = {Paprocki, Valerie and Hrob{\´a}rik, Peter and Harriman, Katie L. M. and Luff, Martin S. and Kupfer, Thomas and Kaupp, Martin and Murugesu, Muralee and Braunschweig, Holger},
  title     = {Ein neutrales 1,4-Diborabenzol als \(\pi\)-Ligand in Actinoidkomplexen},
  series = {Angewandte Chemie},
  volume    = {132},
  journal   = {Angewandte Chemie},
  number    = {31},
  doi       = {10.1002/ange.202004501},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218181},
  pages     = {13209 -- 13216},
  year      = {2020},
  abstract  = {Die \(\pi\)-Koordination von Aren- und anionischen Heteroarenliganden ist ein allgegenw{\"a}rtiges Strukturmotiv in der metallorganischen Chemie der d- und f-Block-Elemente. Im Gegensatz dazu sind vergleichbare \(\pi\)-Wechselwirkungen neutraler Heteroarene, darunter auch solche neutraler, aromatischer Borheterocyclen, f{\"u}r den f-Block weit weniger verbreitet, was z. T. mit einer geringeren Effektivit{\"a}t der Metall-zu-Ligand-R{\"u}ckbindung in Zusammenhang gebracht werden kann. F{\"u}r die Actinoide sind π-Komplexe mit neutralen Heteroarenliganden sogar g{\"a}nzlich unbekannt. Durch Ausnutzung der außergew{\"o}hnlichen \(\pi\)-Donorst{\"a}rke eines 1,4-Diborabenzols ist es uns nun gelungen, eine Reihe stabiler π-Halbsandwichkomplexe des Thoriums(IV) und des Urans(IV) {\"u}ber einen erstaunlich einfachen Zugang zu generieren: Umsetzung eines 1,4-Diborabenzols mit ThCl\(_{4}\)(dme)\(_{2}\) bzw. UCl\(_{4}\) in Gegenwart einer Lewis-Base. Hierdurch konnten die ersten Beispiele f{\"u}r Actinoidkomplexe mit einem neutralen Borheterocyclus als Sandwich-artigem Liganden erhalten werden. Laut experimentellen und theoretischen Studien ist die starke Actinoid-Heteroaren-Wechselwirkung in diesen Molek{\"u}len im Wesentlichen von elektrostatischer Natur. Der kovalente Hauptbeitrag wird hingegen von der Ligand-zu-Metall-\(\pi\)-Wechselwirkung geleistet, w{\"a}hrend \(\pi\)/δ-R{\"u}ckbindungsanteile kaum eine Rolle spielen.},
  language  = {de}
}