Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-16024 unpublished Böhnke, Julian; Dellermann, Theresa; Celik, Mehmet Ali; Krummenacher, Ivo; Dewhurst, Rian D.; Demeshko, Serhiy; Ewing, William C.; Hammond, Kai; Heß, Merlin; Bill, Eckhard; Welz, Eileen; Röhr, Merle I. S.; Mitric, Roland; Engels, Bernd; Meyer, Franc; Braunschweig, Holger Isolation of diradical products of twisted double bonds Molecules containing multiple bonds between atoms—most often in the form of olefins—are ubiquitous in nature, commerce, and science, and as such have a huge impact on everyday life. Given their prominence, over the last few decades, frequent attempts have been made to perturb the structure and reactivity of multiply-bound species through bending and twisting. However, only modest success has been achieved in the quest to completely twist double bonds in order to homolytically cleave the associated π bond. Here, we present the isolation of double-bond-containing species based on boron, as well as their fully twisted diradical congeners, by the incorporation of attached groups with different electronic properties. The compounds comprise a structurally authenticated set of diamagnetic multiply-bound and diradical singly-bound congeners of the same class of compound. 2018 Nature Communications urn:nbn:de:bvb:20-opus-160248 Institut für Anorganische Chemie OPUS4-16043 Wissenschaftlicher Artikel Böhnke, Julian; Dellermann, Theresa; Celik, Mehmet Ali; Krummenacher, Ivo; Dewhurst, Rian D.; Demeshko, Serhiy; Ewing, William C.; Hammond, Kai; Heß, Merlin; Bill, Eckhard; Welz, Eileen; Röhr, Merle I. S.; Mitric, Roland; Engels, Bernd; Meyer, Franc; Braunschweig, Holger Isolation of diborenes and their 90°-twisted diradical congeners Molecules containing multiple bonds between atoms—most often in the form of olefins—are ubiquitous in nature, commerce, and science, and as such have a huge impact on everyday life. Given their prominence, over the last few decades, frequent attempts have been made to perturb the structure and reactivity of multiply-bound species through bending and twisting. However, only modest success has been achieved in the quest to completely twist double bonds in order to homolytically cleave the associated π bond. Here, we present the isolation of double-bond-containing species based on boron, as well as their fully twisted diradical congeners, by the incorporation of attached groups with different electronic properties. The compounds comprise a structurally authenticated set of diamagnetic multiply-bound and diradical singly-bound congeners of the same class of compound. 2018 Nature Communications 9 Article number: 1197 urn:nbn:de:bvb:20-opus-160431 10.1038/s41467-018-02998-3 Institut für Anorganische Chemie OPUS4-31258 Wissenschaftlicher Artikel Weiser, Jonas; Cui, Jingjing; Dewhurst, Rian D.; Braunschweig, Holger; Engels, Bernd; Fantuzzi, Felipe Structure and bonding of proximity-enforced main-group dimers stabilized by a rigid naphthyridine diimine ligand The development of ligands capable of effectively stabilizing highly reactive main-group species has led to the experimental realization of a variety of systems with fascinating properties. In this work, we computationally investigate the electronic, structural, energetic, and bonding features of proximity-enforced group 13-15 homodimers stabilized by a rigid expanded pincer ligand based on the 1,8-naphthyridine (napy) core. We show that the redox-active naphthyridine diimine (NDI) ligand enables a wide variety of structural motifs and element-element interaction modes, the latter ranging from isolated, element-centered lone pairs (e.g., E = Si, Ge) to cases where through-space π bonds (E = Pb), element-element multiple bonds (E = P, As) and biradical ground states (E = N) are observed. Our results hint at the feasibility of NDI-E2 species as viable synthetic targets, highlighting the versatility and potential applications of napy-based ligands in main-group chemistry. 2023 11 Journal of Computational Chemistry 44 3 456 467 urn:nbn:de:bvb:20-opus-312586 10.1002/jcc.26994 Institut für Anorganische Chemie OPUS4-25645 Wissenschaftlicher Artikel Brückner, Tobias; Fantuzzi, Felipe; Stennett, Tom E.; Krummenacher, Ivo; Dewhurst, Rian D.; Engels, Bernd; Braunschweig, Holger Isolation of neutral, mono-, and dicationic B\(_2\)P\(_2\) rings by diphosphorus addition to a boron-boron triple bond The NHC-stabilised diboryne (B\(_2\)(SIDep)\(_2\); SIDep=1,3-bis(2,6-diethylphenyl)imidazolin-2-ylidene) undergoes a high-yielding P−P bond activation with tetraethyldiphosphine at room temperature to form a B\(_2\)P\(_2\) heterocycle via a diphosphoryldiborene by 1,2-diphosphination. The heterocycle can be oxidised to a radical cation and a dication, respectively, depending on the oxidant used and its counterion. Starting from the planar, neutral 1,3-bis(alkylidene)-1,3-diborata-2,4-diphosphoniocyclobutane, each oxidation step leads to decreased B−B distances and loss of planarity by cationisation. X-ray analyses in conjunction with DFT and CASSCF/NEVPT2 calculations reveal closed-shell singlet, butterfly-shaped structures for the NHC-stabilised dicationic B\(_2\)P\(_2\) rings, with their diradicaloid, planar-ring isomers lying close in energy. 2021 13661–13665 Angewandte Chemie International Edition 60 24 urn:nbn:de:bvb:20-opus-256451 10.1002/anie.202102218 Institut für Anorganische Chemie OPUS4-24480 Wissenschaftlicher Artikel Hagspiel, Stephan; Fantuzzi, Felipe; Dewhurst, Rian D.; Gärtner, Annalena; Lindl, Felix; Lamprecht, Anna; Braunschweig, Holger Addukte des Stammboraphosphaketens H\(_{2}\)BPCO und deren Insertionsreaktionen mittels Decarbonylierung Die ersten Beispiele für Lewis-Basen-Addukte des Stammboraphosphaketens H\(_{2}\)B-PCO und ihre cyclischen Dimere wurden hergestellt. Eines dieser Addukte zeigt unter milden Bedingungen eine Decarbonylierung und anschließende Insertion des Phosphinidens in die B-C-Bindung eines Borols, was in der Bildung sehr seltener Beispiele für 1,2-Phosphaborinine, B,P-Isostere von Benzol, resultiert. Die starken Donoreigenschaften dieser 1,2-Phosphaborinine wurden durch die Synthese ihrer π-Komplexe mit Metallen der Gruppe 6 bestätigt. 2021 4 Angewandte Chemie 133 24 13780 13784 urn:nbn:de:bvb:20-opus-244803 10.1002/ange.202103521 Institut für Anorganische Chemie OPUS4-21965 Wissenschaftlicher Artikel Muessig, Jonas H.; Lisinetskaya, Polina; Dewhurst, Rian D.; Bertermann, Rüdiger; Thaler, Melanie; Mitric, Roland; Braunschweig, Holger Dibortetraiodid (B\(_2\)I\(_4\)) ist im Festkörper ein Polymer aus sp3-hybridisiertem Bor Anhand der ersten Festkörperstrukturen 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 Aggregatzuständen in Form diskreter Moleküle mit planaren, dreifach koordinierten Boratomen vorliegt. Röntgenstrukturanalysen, Festkörper-NMR- und IR-Messungen zeigen, dass B\(_2\)I\(_4\) im Festkörper in zwei polymeren Konformeren vorkommt, die tetraedrisch koordinierte Boratome enthalten. Anhand von DFT-Rechnungen werden die IR-Spektren in Lösung und im Festkörper simuliert und mit den experimentellen Daten verglichen. 2020 5574-5579 Angewandte Chemie 132 14 urn:nbn:de:bvb:20-opus-219653 10.1002/ange.201913590 Institut für Anorganische Chemie OPUS4-20942 Wissenschaftlicher Artikel Muessig, Jonas H.; Lisinetskaya, Polina; Dewhurst, Rian D.; Bertermann, Rüdiger; Thaler, Melanie; Mitric, Roland; Braunschweig, Holger Tetraiododiborane(4) (B\(_2\)I\(_4\)) is a Polymer based on sp\(^3\) Boron in the Solid State Herein we present the first solid-state structures of tetraiododiborane(4) (B\(_2\)I\(_4\)), which was long believed to exist in all phases as discrete molecules with planar, tricoordinate boron atoms, like the lighter tetrahalodiboranes(4) B\(_2\)F\(_4\), B\(_2\)Cl\(_4\), and B\(_2\)Br\(_4\). Single-crystal X-ray diffraction, solid-state NMR, and IR measurements indicate that B\(_2\)I\(_4\) in fact exists as two different polymeric forms in the solid state, both of which feature boron atoms in tetrahedral environments. DFT calculations are used to simulate the IR spectra of the solution and solid-state structures, and these are compared with the experimental spectra. 2020 5531-5535 Angewandte Chemie International Edition 59 urn:nbn:de:bvb:20-opus-209428 10.1002/anie.201913590 Institut für Anorganische Chemie OPUS4-25699 Wissenschaftlicher Artikel Cui, Jingjing; Dietz, Maximilian; Härterich, Marcel; Fantuzzi, Felipe; Lu, Wei; Dewhurst, Rian D.; Braunschweig, Holger Diphosphino-Functionalized 1,8-Naphthyridines: a Multifaceted Ligand Platform for Boranes and Diboranes A 1,8-naphthyridine diphosphine (NDP) reacts with boron-containing Lewis acids to generate complexes featuring a number of different naphthyridine bonding modes. When exposed to diborane B\(_{2}\)Br\(_{4}\), NDP underwent self-deprotonation to afford [NDP-B\(_{2}\)Br\(_{3}\)]Br, an unsymmetrical diborane comprised of four fused rings. The reaction of two equivalents of monoborane BBr\(_{3}\) and NDP in a non-polar solvent provided the simple phosphine-borane adduct [NDP(BBr\(_{3}\))\(_{2}\)], which then underwent intramolecular halide abstraction to furnish the salt [NDP-BBr\(_{2}\)][BBr\(_{4}\)], featuring a different coordination mode from that of [NDP-B\(_{2}\)Br\(_{3}\)]Br. Direct deprotonation of NDP by KHMDS or PhCH2K generates mono- and dipotassium reagents, respectively. The monopotassium reagent reacts with one or half an equivalent of B\(_{2}\)(NMe\(_{2}\))\(_{2}\)Cl\(_{2}\) to afford NDP-based diboranes with three or four amino substituents. 2021 15751–15756 Chemistry—A European Journal 27 63 urn:nbn:de:bvb:20-opus-256994 10.1002/chem.202102721 Institut für Anorganische Chemie OPUS4-25663 Wissenschaftlicher Artikel Schmidt, Paul; Fantuzzi, Felipe; Klopf, Jonas; Schröder, Niklas B.; Dewhurst, Rian D.; Braunschweig, Holger; Engel, Volker; Engels, Bernd Twisting versus delocalization in CAAC- and NHC-stabilized boron-based biradicals: the roles of sterics and electronics Twisted boron-based biradicals featuring unsaturated C\(_2\)R\(_2\) (R=Et, Me) bridges and stabilization by cyclic (alkyl)(amino)carbenes (CAACs) were recently prepared. These species show remarkable geometrical and electronic differences with respect to their unbridged counterparts. Herein, a thorough computational investigation on the origin of their distinct electrostructural properties is performed. It is shown that steric effects are mostly responsible for the preference for twisted over planar structures. The ground-state multiplicity of the twisted structure is modulated by the σ framework of the bridge, and different R groups lead to distinct multiplicities. In line with the experimental data, a planar structure driven by delocalization effects is observed as global minimum for R=H. The synthetic elusiveness of C\(_2\)R\(_2\)-bridged systems featuring N-heterocyclic carbenes (NHCs) was also investigated. These results could contribute to the engineering of novel main group biradicals. 2021 5160–5170 Chemistry - A European Journal 27 16 urn:nbn:de:bvb:20-opus-256636 10.1002/chem.202004619 Institut für Anorganische Chemie OPUS4-22444 Wissenschaftlicher Artikel Roy, Dipak Kumar; Tröster, Tobias; Fantuzzi, Felipe; Dewhurst, Rian D.; Lenczyk, Carsten; Radacki, Krzysztof; Pranckevicius, Conor; Engels, Bernd; Braunschweig, Holger Isolation and Reactivity of an Antiaromatic s-Block Metal Compound The concepts of aromaticity and antiaromaticity have a long history, and countless demonstrations of these phenomena have been made with molecules based on elements from the p, d, and f blocks of the periodic table. In contrast, the limited oxidation-state flexibility of the s-block metals has long stood in the way of their participation in sophisticated π-bonding arrangements, and truly antiaromatic systems containing s-block metals are altogether absent or remain poorly defined. Using spectroscopic, structural, and computational techniques, we present herein the synthesis and authentication of a heterocyclic compound containing the alkaline earth metal beryllium that exhibits significant antiaromaticity, and detail its chemical reduction and Lewis-base-coordination chemistry. 2021 7 Angewandte Chemie International Edition 60 7 3812 3819 urn:nbn:de:bvb:20-opus-224447 10.1002/anie.202014557 Institut für Anorganische Chemie