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1.
Dr. Oliver Hegen Jens Braese Prof. Dr. Alexey Y. Timoshkin Prof. Dr. Manfred Scheer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):485-489
A new class of neutral bidentate ligands with pnictogenyl-functional sites has been obtained. The reaction of tmeda⋅(BH2I)2 ( 1 , tmeda=tetramethylethylendiamine) with different phosphanides yields the corresponding bidentate phosphanylboranes tmeda⋅(BH2PH2)2 ( 2 a ), tmeda⋅(BH2PPh2)2 ( 2 b ), and tmeda⋅(BH2tBuPH)2 ( 2 c ). This reaction strategy could be further extended to synthesize the first bidentate arsanylborane tmeda⋅(BH2AsPh2)2 ( 3 ). Depending on the substituents on the phosphorus, these compounds form different AuI complexes, to build either polymeric tmeda⋅(BH2PH2AuCl)2 ( 4 a ), or monomeric tmeda⋅(BH2PPh2AuCl)2 ( 4 b ) products. These compounds form also neutral oligomeric group 13/15 chain-like molecules by coordination to a boron moiety such as tmeda⋅(BH2PH2BH3)2 ( 5 a ) and tmeda⋅(BH2AsPh2BH3)2 ( 5 b ). DFT calculations provide insight into the differences between the syntheses of mono- and bidentate pnictogenylboranes. 相似文献
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4.
Christoph Riesinger Prof. Dr. Fabian Dielmann Robert Szlosek Dr. Alexander V. Virovets Prof. Dr. Manfred Scheer 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218828
The thermolysis of Cp′′′Ta(CO)4 with white phosphorus (P4) gives access to [{Cp′′′Ta}2(μ,η2 : 2 : 2 : 2 : 1 : 1-P8)] ( A ), representing the first complex containing a cyclooctatetraene-like (COT) cyclo-P8 ligand. While ring sizes of n >6 have remained elusive for cyclo-Pn structural motifs, the choice of the transition metal, co-ligand and reaction conditions allowed the isolation of A . Reactivity investigations reveal its versatile coordination behaviour as well as its redox properties. Oxidation leads to dimerization to afford [{Cp′′′Ta}4(μ4,η2 : 2 : 2 : 2 : 2 : 2 : 2 : 2 : 1 : 1 : 1 : 1-P16)][TEF]2 ( 4 , TEF=[Al(OC{CF3}3)4]−). Reduction, however, leads to the fission of one P−P bond in A followed by rapid dimerization to form [K@[2.2.2]cryptand]2[{Cp′′′Ta}4(μ4,η2 : 2 : 2 : 2 : 2 : 2 : 2 : 2 : 1 : 1 : 1 : 1-P16)] ( 5 ), which features an unprecedented chain-type P16 ligand. Lastly, A serves as a P2 synthon, via ring contraction to the triple-decker complex [{Cp′′′Ta}2(μ,η6 : 6-P6)] ( B ). 相似文献
5.
Cover Picture: Metal‐Free Addition/Head‐to‐Tail Polymerization of Transient Phosphinoboranes,RPH‐BH2: A Route to Poly(alkylphosphinoboranes) (Angew. Chem. Int. Ed. 46/2015) 下载免费PDF全文
6.
Dr. Benedict M. Gardner Dr. Gábor Balázs Prof. Dr. Manfred Scheer Dr. Ashley J. Wooles Dr. Floriana Tuna Prof. Eric J. L. McInnes Dr. Jonathan McMaster Dr. William Lewis Prof. Dr. Alexander J. Blake Prof. Dr. Stephen T. Liddle 《Angewandte Chemie (International ed. in English)》2015,54(50):15250-15254
The HAsAsH molecule has hitherto only been proposed tentatively as a short‐lived species generated in electrochemical or microwave‐plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(TrenTIPS)}2(μ‐η2:η2‐As2H2)] ( 3 , TrenTIPS=N(CH2CH2NSiPri3)3; Pri=CH(CH3)2). Complex 3 was prepared by deprotonation and oxidative homocoupling of an arsenide precursor. Characterization and computational data are consistent with back‐bonding‐type interactions from uranium to the HAsAsH π*‐orbital. This experimentally confirms the theoretically predicted excellent π‐acceptor character of HAsAsH, and is tantamount to full reduction to the diarsane‐1,2‐diide form. 相似文献
7.
Redox and Coordination Behavior of the Hexaphosphabenzene Ligand in [(Cp*Mo)2(μ,η6:η6‐P6)] Towards the “Naked” Cations Cu+, Ag+, and Tl+ 下载免费PDF全文
Martin Fleischmann Fabian Dielmann Laurence J. Gregoriades Eugenia V. Peresypkina Alexander V. Virovets Sebastian Huber Alexey Y. Timoshkin Gbor Balzs Manfred Scheer 《Angewandte Chemie (International ed. in English)》2015,54(44):13110-13115
Although the cyclo‐P6 complex [(Cp*Mo)2(μ,η6:η6‐P6)] ( 1 ) was reported 30 years ago, little is known about its chemistry. Herein, we report a high‐yielding synthesis of 1 , the complex 2 , which contains an unprecedented cyclo‐P10 ligand, and the reactivity of 1 towards the “naked” cations Cu+, Ag+, and Tl+. Besides the formation of the single oxidation products 3 a,b which have a bisallylic distorted cyclo‐P6 middle deck, the [M( 1 )2]+ complexes are described which show distorted square‐planar (M=Cu( 4 a ), Ag( 4 b )) or distorted tetrahedral coordinated (M=Cu( 5 )) M+ cations. The choice of solvent enabled control over the reaction outcome for Cu+, as proved by powder XRD and supported by DFT calculations. The reaction with Tl+ affords a layered two‐dimensional coordination network in the solid state. 相似文献
8.
Maria Haimerl Dr. Christian Graßl Dr. Michael Seidl Dr. Martin Piesch Prof. Dr. Manfred Scheer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):18129-18134
The reactivity of white phosphorus and yellow arsenic towards two different nickel nacnac complexes is investigated. The nickel complexes [(L1Ni)2tol] ( 1 , L1=[{N(C6H3iPr2-2,6)C(Me)}2CH]−) and [K2][(L1Ni)2(μ,η1 : 1-N2)] ( 6 ) were reacted with P4, As4 and the interpnictogen compound AsP3, respectively, yielding the homobimetallic complexes [(L1Ni)2(μ-η2,κ1:η2,κ1-E4)] (E=P ( 2 a ), As ( 2 b ), AsP3 ( 2 c )), [(L1Ni)2(μ,η3 : 3-E3)] (E=P ( 3 a ), As ( 3 b )) and [K@18-c-6(thf)2][L1Ni(η1 : 1-E4)] (E=P ( 7 a ), As ( 7 b )), respectively. Heating of 2 a , 2 b or 2 c also leads to the formation of 3 a or 3 b . Furthermore, the reactivity of these compounds towards reduction agents was investigated, leading to [K2][(L1Ni)2(μ,η2 : 2-P4)] ( 4 ) and [K@18-c-6(thf)3][(L1Ni)2(μ,η3 : 3-E3)] (E=P ( 5 a ), As ( 5 b )), respectively. Compound 4 shows an unusual planarization of the initial Ni2P4-prism. All products were comprehensively characterized by crystallographic and spectroscopic methods. 相似文献
9.
Dr. Martin Piesch Dr. Amélie Nicolay Dr. Maria Haimerl Dr. Michael Seidl Dr. Gábor Balázs Prof. T. Don Tilley Prof. Dr. Manfred Scheer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201144
The bridging MeCN ligand in the dicopper(I) complexes [(DPFN)Cu2(μ,η1 : η1-MeCN)][X]2 (X=weakly coordinating anion, NTf2 ( 1 a ), FAl[OC6F10(C6F5)]3 ( 1 b ), Al[OC(CF3)3]4 ( 1 c )) was replaced by white phosphorus (P4) or yellow arsenic (As4) to yield [(DPFN)Cu2(μ,η2 : η2-E4)][X]2 (E=P ( 2 a – c ), As ( 3 a – c )). The molecular structures in the solid state reveal novel coordination modes for E4 tetrahedra bonded to coinage metal ions. Experimental data and quantum chemical computations provide information concerning perturbations to the bonding in coordinated E4 tetrahedra. Reactions with N-heterocyclic carbenes (NHCs) led to replacement of the E4 tetrahedra with release of P4 or As4 and formation of [(DPFN)Cu2(μ,η1 : η1-MeNHC)][X]2 ( 4 a,b ) or to an opening of one E−E bond leading to an unusual E4 butterfly structural motif in [(DPFN)Cu2(μ,η1 : η1-E4DippNHC)][X]2 (E=P ( 5 a,b ), E=As ( 6 )). With a cyclic alkyl amino carbene (EtCAAC), cleavage of two As−As bonds was observed to give two isomers of [(DPFN)Cu2(μ,η2 : η2-As4EtCAAC)][X]2 ( 7 a,b ) with an unusual As4-triangle+1 unit. 相似文献