TY  - THES
A1  - Kelch, Hauke
T1  - Synthese und Reaktivität neuer Bor-haltiger Heterocyclen UND Element-Element-Bindungsaktivierungen durch vicinale Biscarbenoide
T1  - Synthesis and Reactivity of Novel Boron Containing Heterocycles AND Element-Element-Bond Activation via Vicinal Biscarbenoids
N2  - Teil 1: Synthese und Reaktivität neuer Bor-haltiger Heterocyclen
Im Rahmen der vorliegenden Arbeit wurden Versuche unternommen, neue Borolverbindungen auf Basis des 2,3,4,5-Tetrakis(pinakolboryl)buta-1,3-diendiyl-Rückgrates mit unterschiedlichen Substituenten am Borzentrum darzustellen. Des Weiteren wurde ein neues Borolsystem auf Basis des Tetraphenylbutadien-Gerüstes synthetisiert, das die elektronenziehende Perfluorphenylgruppe als Bor-ständigen Substituenten trägt. Durch experimentelle Gegenüberstellung der strukturellen und spektroskopischen Parameter konnte - unterstützt durch quantenchemische Berechnungen - der Einfluss der Rückgratsubstitution eingehend untersucht werden. 

Teil 2: Element-Element-Bindungsaktivierungen durch vicinale Biscarbenoide
Im Rahmen der vorliegenden Arbeit wurde das vicinale Biscarbenoid Bis(piperidyl)acetylen eingesetzt um die Reaktivität dieser Verbindungsklasse gegenüber Lewis-sauren Hauptgruppenelementverbindungen aufzuklären.
N2  - Part 1: Synthesis and Reactivity of Novel Boron Containing Heterocycles
The synthesis of novel 2,3,4,5-tetrakis(pinacolatoboryl) substituted boroles has been attempted in this work. A novel borole based on the tetraphenyl backbone has been synthesized using the electron withdrawing perfluorphenyl substituent at boron, allowing accurate determinaton of the backbone influence on the electronic properties of boroles. 

Part 2: Element-Element Bond Activation via Vicinal Biscarbenoids 
The vicinal biscarbenoid bis(piperidyl)acetylene was used to probe the reactivity of this class of compounds towards Lewis-acidic main group reagents.
KW  - Borheterocyclen
KW  - Carbenoide
KW  - Bindungsaktivierung
KW  - Umlagerung
KW  - Antiaromatizität
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-153951
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  -