30 research outputs found
Beiträge zur phasenabhängigen Strukturchemie von Hauptgruppenelementverbindungen
No full textGlodde T. Beiträge zur phasenabhängigen Strukturchemie von Hauptgruppenelementverbindungen. Bielefeld: Universität Bielefeld; 2020
Ein Schwefelmonoxid‐Addukt eines frustrierten Sn/P‐Lewis‐Paares
No full textHoltkamp P, Glodde T, Poier D, Neumann B, Stammler H-G, Mitzel NW. Ein Schwefelmonoxid‐Addukt eines frustrierten Sn/P‐Lewis‐Paares. Angewandte Chemie. 2020;132(40):17541-17545.Die Reaktion des geminalen frustrierten Lewis-Paares (F5C2)3SnCH2P(tBu)2(1) mit N-Sulfinylanilin PhNSOergab das erste Schwefelmonoxid-Addukt eines Hauptgrup-penmetalls (F5C2)3SnCH2P(tBu)2·SO (2). Es enthält einenSnCPSO-Ring. Das zweite Produkt ist ein Phenylnitren-Addukt von1. Die überraschende Stabilität von2wurde mitdenen der bisher unzugänglichen O2- und S2-Addukte von1verglichen. Versuche, diese aus1und den elementarenChalkogenen (O2,S8,Se1,Te1) herzustellen, führten zu vier-gliedrigen SnCPE-Ringsystemen. Quantenchemische Unter-suchungen von2zeigen den Beitrag der Bindungspolarität derSO-Einheit zur Stabilisierung von2
Solid-state molecular structures of Se(IV) and Te(IV) dihalides X2Se(CH3)(C6F5) and the gas-phase structure of Se(CH3)(C6F5)
No full textGlodde T, Neumann B, Stammler H-G, Mitzel NW. Solid-state molecular structures of Se(IV) and Te(IV) dihalides X2Se(CH3)(C6F5) and the gas-phase structure of Se(CH3)(C6F5). Zeitschrift für Naturforschung B, Journal of Chemical Sciences. 2023.In a systematic study the Se(IV) and Te(IV) dihalides F2E(CH3)(C6F5), Cl2E(CH3)(C6F5) and Br2E(CH3)(C6F5) (E = Se, Te) have been synthesized and their crystal and molecular structures been investigated by X-ray diffraction and computational methods. The solid-state structures of all compounds show significant correlations between the lengths of the E-C1 bond and the intermolecular E & BULL;& BULL;& BULL;X (X = F, Cl and Br) contacts, indicating the presence of sigma-hole interactions. For comparison, the crystal and gas phase (electron diffraction) structures of Se(CH3)(C6F5) are presented as well. They show very similar structural parameters in both phases. The structures of the single molecules X2E(CH3)(C6F5) have been analyzed by quantum-chemical methods in terms of their surface potentials. They show significant similarities of their molecular electrostatic-potential topologies (V (s,max)). The magnitude of V (s,max) correlates with the aggregation pattern
Isolation of a Ge(I) Diradicaloid and Dihydrogen Splitting
No full textSharma MK, Ebeler F, Glodde T, Neumann B, Stammler H-G, Ghadwal R. Isolation of a Ge(I) Diradicaloid and Dihydrogen Splitting. Journal of the American Chemical Society. 2021;143(1):121–125.The cyclic Ge(I) compound [(ADCPh)Ge]2 (4) (ADCPh = {CN(Dipp)}2CPh, Dipp = 2,6-iPr2C6H3) containing a 6π-electron C4Ge2 framework has been isolated as a red crystalline solid. CASSCF calculations reveal a closed-shell singlet ground state for 4 with a considerable diradical character (y = 34%). Thus, the diradicaloid 4 readily splits dihydrogen at room temperature to yield the elusive bis-hydridogermylene [(ADCPh)GeH]2 (5)
An Adduct of Sulfur Monoxide to a Frustrated Sn/P Lewis Pair
No full textHoltkamp P, Glodde T, Poier D, Neumann B, Stammler H-G, Mitzel NW. An Adduct of Sulfur Monoxide to a Frustrated Sn/P Lewis Pair. Angewandte Chemie (International ed. in English). 2020;59(40):17388-17392.The geminal frustrated Lewis pair (F5C2)3SnCH2P(tBu)2 (1) reacted with N‐sulfinylaniline PhNSO to afford the first sulfur monoxide adduct of a main group metal, (F5C2)3SnCH2P(tBu)2⋅SO (2), which contains a SnCPSO ring. The second product is a phenylnitrene adduct of 1. The surprising stability of 2 was compared with the stabilities of the so far inaccessible O2 and S2 adducts of 1. Attempts to prepare these from 1 and the elemental chalcogens (O2, S8, Se∞, Te∞) led to four‐membered SnCPE ring systems. Quantum‐chemical investigations of 2 demonstrate the bond polarity of the SO unit to stabilize 2
A crystalline C5-protonated 1,3-imidazol-4-ylidene.
No full textRottschäfer D, Glodde T, Neumann B, Stammler H-G, Ghadwal R. A crystalline C5-protonated 1,3-imidazol-4-ylidene. Chemical communications (Cambridge, England). 2020;56(13):2027-2030.The first C5-protonated 1,3-imidazol-based mesoionic carbene iMICBp (2) (iMICBp = :C{CH(NDipp)2C(Bp)}; Dipp = 2,6-iPr2C6H3; Bp = 4-PhC6H4) has been reported as a crystalline solid. Spectroscopic, X-ray diffraction, and computational studies clearly support the carbenic nature of 2, which has been further corroborated by its reactions with Ni(CO)4, (Me2S)AuCl, white phosphorus, and CO2
Synthesis of Bifunctional Boron-Lewis Acids - Thorough Investigation of the Adduct Formation with Pyrimidine
No full textRudlof J, Glodde T, Mix A, Neumann B, Stammler H-G, Mitzel NW. Synthesis of Bifunctional Boron-Lewis Acids - Thorough Investigation of the Adduct Formation with Pyrimidine. European Journal of Inorganic Chemistry . 2022: e202100842.Three bifunctional boron-Lewis acids based on a 1,2-diethynylbenzene backbone were synthesized using a tin-boron exchange protocol in good to very good yields. Complexation experiments with pyrimidine were thoroughly investigated using the example of 1,2-bis(benzo[d][1,3,2]dioxaborol-2-ylethynyl)benzene (3) in solution, in the solid phase and by quantum-chemical calculations. Two adducts were structurally investigated by X-ray diffraction experiments. DOSY-/VT-NMR experiments gave insight into the dynamic behaviour of the synthesized poly-Lewis acids with pyrimidine
Isolierung von 1,4‐Diarsinin‐1,4‐diid‐ und 1,4‐Diarsinin‐Derivaten
No full textRottschäfer D, Glodde T, Neumann B, Stammler H-G, Andrada DM, Ghadwal R. Isolierung von 1,4‐Diarsinin‐1,4‐diid‐ und 1,4‐Diarsinin‐Derivaten. Angewandte Chemie. 2021;133(29):15983-15987.Das 1,4-Diarsinin-1,4-diid [(ADCPh)As]2 (5) (ADCPh={C(DippN)}2CPh, Dipp=2,6-iPr2C6H3) mit einem planaren C4As2-Ring, der an zwei 1,3-Imidazol-Ringen anelliert ist, wurde als roter, kristalliner Feststoff isoliert. Verbindung 5, die formal einen 8p-Elektronen-C4As2-Ring enthält, ist antiaromatisch und geht eine 2e-Oxidation mit AgOTf ein, die zum aromatischen 6p-Elektronen-System [(ADCPh)As]2-(OTf)2 (6) führt
Ein offenschaliges Singulett‐SnI‐Diradikal und H2‐Spaltung
No full textSharma MK, Rottschäfer D, Glodde T, Neumann B, Stammler H-G, Ghadwal R. Ein offenschaliges Singulett‐SnI‐Diradikal und H2‐Spaltung. Angewandte Chemie. 2021;133(12):6485-6489.Das erste SnI‐Diradikal [(ADCPh)Sn]2 (4) auf Basis eines anionischen Dicarbengerüsts (ADCPh={CN(Dipp)}2CPh; Dipp=2,6‐iPr2C6H3) wurde als grüner, kristalliner Feststoff durch KC8‐Reduktion des entsprechenden Bis‐Chlorstannylens [(ADCPh)SnCl]2 (3) isoliert. Der sechsgliedrige C4Sn2‐Ring von 4, der sechs π‐Elektronen enthält, zeigt einen diatropen Ringstrom, sodass 4 auch als das erste 1,4‐Distannabenzol‐Derivat bezeichnet werden kann. DFT‐Rechnungen deuten auf einen offenschaligen Singulett (OS)‐Grundzustand von 4 mit einer bemerkenswert kleinen Singulett‐Triplett‐Energielücke (ΔEOS–T=4.4 kcal mol−1) hin, was mit CASSCF‐Rechnungen (ΔES–T=6.6 kcal mol−1 und Diradikal‐Charakter y=37 %) übereinstimmt. Das Diradikal 4 spaltet bei Raumtemperatur H2 auf und liefert das Bis‐Hydridostannylen [(ADCPh)SnH]2 (5). Die weitere Reaktivität von 4 wurde mit PhSeSePh und MeOTf untersucht
Structures and Properties of trans‐1,3,3,3‐Tetrafluoro‐ propene (HFO‐1234ze) and 2,3,3,3‐Tetrafluoropropene (HFO‐1234yf) Refrigerants
No full textSchwabedissen J, Glodde T, Vishnevskiy Y, et al. Structures and Properties of trans‐1,3,3,3‐Tetrafluoro‐ propene (HFO‐1234ze) and 2,3,3,3‐Tetrafluoropropene (HFO‐1234yf) Refrigerants . ChemistryOpen. 2020;9(9):921-928.The refrigerant trans‐1,3,3,3‐tetrafluoropropene (HFO‐1234ze) is used as a replacement for former cooling agents that have been phased‐out due to their global warming potential or ozone depleting potential. Although it is used on a large scale, only a few vibrational data and no structural data of HFO‐1234ze are known. We report structure determinations based on low‐temperature single‐crystal X‐ray diffraction data as well as gas‐phase diffraction data of HFO‐1234ze and HFO‐1234yf (2,3,3,3‐tetrafluoropropene). Furthermore, vibrational spectra of HFO‐1234ze in all phases are described. The results are discussed together with quantum‐chemical calculations on the PBE0/cc‐pVTZ level of theory. Combustion experiments of HFO‐1234ze show carbonyl difluoride, carbon dioxide and hydrogen fluoride to be the main combustion products
