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1.
Sodium‐ion batteries (SIBs) have received much attention, owing to their great potential for large‐scale application. A lack of efficient anode materials with high reversible capacity is one main challenge facing the development of SIBs. Antimony‐ and bismuth‐based chalcogenides materials can store large amounts of Na+ ions, owing to the alloying/dealloying reaction mechanism within a low potential range, and thus, are regarded as promising anodes for SIBs. However, these materials face great challenges of poor ion diffusion rate, multiple phase transformations, and severe morphology pulverization. Herein, recent developments in antimony‐ and bismuth‐based chalcogenides materials, mainly rational structural design strategies used and the electrochemical reaction mechanisms involved, are summarized. Perspectives for further improving antimony‐ and bismuth‐based chalcogenides anodes are also provided. 相似文献
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Sandra Wilfert Helena Henke Wolfgang Schoefberger Oliver Brüggemann Ian Teasdale 《Macromolecular rapid communications》2014,35(12):1135-1141
A simple polymerization of trichlorophosphoranimine (Cl3P = N−SiMe3) mediated by functionalized triphenylphosphines is presented. In situ initiator formation and the subsequent polymerization progress are investigated by 31P NMR spectroscopy, demonstrating a living cationic polymerization mechanism. The polymer chain lengths and molecular weights of the resulting substituted poly(organo)phosphazenes are further studied by 1H NMR spectroscopy and size exclusion chromatography. This strategy facilitates the preparation of polyphosphazenes with controlled molecular weights and specific functional groups at the α‐chain end. Such well‐defined, mono‐end‐functionalized polymers have great potential use in bioconjugation, surface modification, and as building blocks for complex macromolecular constructs.
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Dr. Shintaro Ishida Fumiya Hirakawa Prof. Dr. Ko Furukawa Dr. Kenji Yoza Prof. Dr. Takeaki Iwamoto 《Angewandte Chemie (International ed. in English)》2014,53(42):11172-11176
Stibinyl and bismuthinyl radicals are recognized as representative intermediates of antimony and bismuth compounds, but still elusive in the condensed phase. We successfully synthesized persistent stibinyl and bismuthinyl radicals in solution by facile dissociation of the corresponding dimers with bulky substituents. We characterized the radicals by NMR and UV/Vis spectroscopy and estimated the thermodynamic parameters for the dissociation equilibria. The radicals show n→p (HOMO→SOMO) transition bands at 497 nm (stibinyl) and 543 nm (bismuthinyl) in 3‐methylpentane and react with a stable nitroxyl radical to give the cross‐radical coupling products in good yields. 相似文献
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Structural,Spectroscopic and Computational Examination of the Dative Interaction in Constrained Phosphine–Stibines and Phosphine–Stiboranes 下载免费PDF全文
Brian A. Chalmers Prof. Michael Bühl Dr. Kasun S. Athukorala Arachchige Prof. Alexandra M. Z. Slawin Dr. Petr Kilian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(20):7520-7531
A series of phosphine–stibine and phosphine–stiborane peri‐substituted acenaphthenes containing all permutations of pentavalent groups ?SbClnPh4–n ( 5 – 9 ), as well as trivalent groups ?SbCl2, ?Sb(R)Cl, and ?SbPh2 ( 2 – 4 , R=Ph, Mes), were synthesised and fully characterised by single crystal diffraction and multinuclear NMR spectroscopy. In addition, the bonding in these species was studied by DFT computational methods. The P–Sb dative interactions in both series range from strongly bonding to non‐bonding as the Lewis acidity of the Sb acceptor is decreased. In the pentavalent antimony series, a significant change in the P–Sb distance is observed between ?SbClPh3 and ?SbCl2Ph2 derivatives 6 and 7 , respectively, consistent with a change from a bonding to a non‐bonding interaction in response to relatively small modification in Lewis acidity of the acceptor. In the SbIII series, two geometric forms are observed. The P–Sb bond length in the SbCl2 derivative 2 is as expected for a normal (rather than a dative) bond. Rather unexpectedly, the phosphine–stiborane complexes 5 – 9 represent the first examples of the σ4P→σ6Sb structural motif. 相似文献
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Dr. Vanessa A. Béland Dr. Paul J. Ragogna 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12751-12757
The development of batteries and fuel cells has brought to light a need for carbon anode materials doped homogeneously with electrocatalytic metals. In particular, combinations of electrocatalysts in carbon have shown promising activity. A method to derive functional carbon materials is the pyrolysis of metallopolymers. This work describes the synthesis of a bifunctional phosphonium-based system derived from a phosphane-ene network. The olefin functionality can be leveraged in a hydrogermylation reaction to functionalize the material with Ge. Unaffected by this radical addition, the bromide counterion of the phosphonium cation can be used to subsequently incorporate a second metal in an ion-complexation reaction with CuBr2. The characterization of the polymers and the derived ceramics are discussed. 相似文献
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Shigeru Yamago Prof. Dr. Takeshi Yamada Dr. Manabu Togai Yuu Ukai Eiichi Kayahara Na Pan Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(4):1018-1029
Several organostibine chain‐transfer agents possessing polar functional groups have been prepared by the reactions of azo initiators and tetramethyldistibine ( 1 ). Carbon‐centered radicals thermally generated from the azo initiators were trapped by 1 to yield the corresponding organostibine chain‐transfer agents. The high yields observed in the synthesis of the chain‐transfer agents strongly suggest that distibines have excellent radicophilic reactivity. As the reactions proceeded under neutral conditions, functional groups that are incompatible with ionic conditions were incorporated into the chain‐transfer agents. The chain‐transfer agents were used in living radical polymerization to synthesize the corresponding α‐functionalized polymers. As the functional groups in the chain‐transfer agents did not interfere with the polymerization reaction, well‐controlled polymers possessing number‐average molecular weights (Mns) predetermined by the monomer/transfer agent ratios were synthesized with low polydispersity indices (PDIs). The organostibanyl ω‐polymer ends were transformed into a number of different functional groups by radical‐coupling, radical‐addition, and oxidation reactions. Therefore, it was possible to synthesize well‐controlled telechelic polymers with the same and also with different functional groups at their α‐ and ω‐polymer ends. Distibine 1 was also found to increase PDI control in the living radical polymerization of styrene and methyl methacrylate (MMA) using a purified organostibine chain‐transfer agent. Well‐controlled poly(methyl methacrylate)s with Mn values ranging from 10 000 to 120 000 with low PDIs (1.05–1.15) were synthesized by the addition of a catalytic amount of 1 . The results have been attributed to the high reactivity of distibine 1 towards polymer‐end radicals, which are spontaneously deactivated to yield organostibine dormant species. 相似文献
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Christoph Helling George E. Cutsail Hanns Weinert Christoph Wlper Stephan Schulz 《Angewandte Chemie (International ed. in English)》2020,59(19):7561-7568
We report on the structures of three unprecedented heteroleptic Sb‐centered radicals [L(Cl)Ga](R)Sb. ( 2‐R , R=B[N(Dip)CH]2 2‐B , 2,6‐Mes2C6H3 2‐C , N(SiMe3)Dip 2‐N ) stabilized by one electropositive metal fragment [L(Cl)Ga] (L=HC[C(Me)N(Dip)]2, Dip=2,6‐i‐Pr2C6H3) and one bulky B‐ ( 2‐B ), C‐ ( 2‐C ), or N‐based ( 2‐N ) substituent. Compounds 2‐R are predominantly metal‐centered radicals. Their electronic properties are largely influenced by the electronic nature of the ligands R, and significant delocalization of unpaired‐spin density onto the ligands was observed in 2‐B and 2‐N . Cyclic voltammetry (CV) studies showed that 2‐B undergoes a quasi‐reversible one‐electron reduction, which was confirmed by the synthesis of [K([2.2.2]crypt)][L(Cl)GaSbB[N(Dip)CH]2] ([K([2.2.2]crypt)][ 2‐B ]) containing the stibanyl anion [ 2‐B ]?, which was shown to possess significant Sb?B multiple‐bonding character. 相似文献
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Yi Liu Dr. Li‐Ming Wu Prof. Dr. Long‐Hua Li Shao‐Wu Du Prof. Dr. John D. Corbett Prof. Dr. Ling Chen Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(29):5305-5308
In phase : The title compounds lie in a new region of phase space for such a structure, and have stoichiometries in accord with a classical Zintl phase formulation. The small semiconductor gaps indicated by DFT calculations are also supported by their diamagnetic susceptibilities.
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Erqing Li Prof. Dr. You Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(12):3520-3527
A novel strategy that involves phosphine‐catalyzed sequential [2+3] and [3+2] annulation reactions was developed. In this domino reaction, γ‐substituted allenoates were used as novel C4 synthons, and the bicyclic cyclopenta[b]dihydrofuran derivatives were produced in good to excellent diastereoselectivities and yields under mild conditions. Furthermore, preliminary studies on an asymmetric variant of this reaction proceeded with moderate enantioselectivity. 相似文献
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A photochemical approach toward the generation of enzyme‐containing redox polymer networks, which are the key material in enzymatic sensors and biofuel cells, is described. The approach is based on the incorporation of photo‐reactive benzophenone groups into the redox polymers. The obtained polymers are then deposited on the surface of glassy carbon electrodes and cross‐linked by illumination with UV light at 365 nm. If this step is done in the presence of the enzyme glucose oxidase, functional electrodes are obtained that yield electrical power upon addition of glucose. This work specifically addresses the question of electrode stability in buffer and demonstrates how slight variations in the chemistry of the redox polymer have a dramatic effect on the electrochemical performance of the electrodes. Different ferrocene‐containing redox polymer networks are synthesized and their properties in physiological buffer are studied.
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Weipeng Lv Shuoqi Liu Xiaobin Fan Shulan Wang Guoliang Zhang Fengbao Zhang 《Macromolecular rapid communications》2010,31(5):454-458
A dextran‐based dual‐sensitive polymer is employed to endow gold nanoparticles with stability and pH‐ and temperature‐sensitivity. The dual‐sensitive polymer is prepared by RAFT polymerization of N‐isopropylacrylamide from trithiocarbonate groups linked to dextran and succinoylation of dextran after polymerization. The functionalized nanoparticles show excellent stability under various conditions and can be stored in powder‐form. UV and DLS measurements confirm that the temperature‐induced optical changes and aggregation behaviors of the particles are strongly dependent on pH.
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《Angewandte Chemie (International ed. in English)》2017,56(2):632-636
One‐electron oxidation of the stibines Aryl3Sb ( 1 , Aryl=2,6‐i Pr2‐4‐OMe‐C6H2; 2 , Aryl=2,4,6‐i Pr3‐C6H2) with AgSbF6 and NaBArylF4 (ArylF=3,5‐(CF3)2C6H3) afforded the first structurally characterized examples of antimony‐centered radical cations 1 .+[BArylF4]− and 2 .+[BArylF4]−. Their molecular and electronic structures were investigated by single‐crystal X‐ray diffraction, electron paramagnetic resonance spectroscopy (EPR) and UV/Vis absorption spectroscopy, in conjunction with theoretical calculations. Moreover, their reactivity was investigated. The reaction of 2 .+[BArylF4]− and p ‐benzoquinone afforded a dinuclear antimony dication salt 3 2+[BArylF4]2−, which was characterized by NMR spectroscopy and X‐ray diffraction analysis. The formation of the dication 3 2+ further confirms that the isolated stibine radical cations are antimony‐centered. 相似文献
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Convenient Synthesis of Functionalized Bis‐ureidopyrimidinones Based on Thiol‐yne Reaction 下载免费PDF全文
Hui‐Qing Peng Cai‐Li Sun Jiang‐Fei Xu Dr. Li‐Ya Niu Dr. Yu‐Zhe Chen Prof. Dr. Li‐Zhu Wu Prof. Dr. Chen‐Ho Tung Prof. Dr. Qing‐Zheng Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11699-11702
The preparation of functionalized bis‐ureidopyrimidinones ( Bis‐UPy ) through the thiol‐yne reaction is described. Various Bis‐UPys with different functional groups were synthesized by using the readily available functionalized alkynes and UPy‐thiol to affirm the simplicity and versatility of the methodology. 相似文献
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Phosphine‐Catalyzed Annulations of 4,4‐Dicyano‐2‐Methylenebut‐3‐enoates with Maleimides and Maleic Anhydride 下载免费PDF全文
Xiao‐Nan Zhang Gen‐Qiang Chen Dr. Xiang‐Ying Tang Dr. Yin Wei Dr. Min Shi 《Angewandte Chemie (International ed. in English)》2014,53(40):10768-10773
A novel phosphine‐catalyzed [4+1] annulation of maleimides with 4,4‐dicyano‐2‐methylenebut‐3‐enoates has been developed to afford spirocyclic products, and the maleimides serves as C1 synthons. Moreover, a phosphine‐catalyzed formal [3+2] annulation between 4,4‐dicyano‐2‐methylenebut‐3‐enoates and maleic anhydride has been also achieved, and maleic anhydride behaved as a C3 synthon in the reaction, thus efficiently affording the functionalized cyclopentenones. A stable phosphinium‐containing zwitterionic compound is the key reactive intermediate in both annulations and was successfully isolated. Plausible mechanisms have been proposed on the basis of control experiments and deuterium‐labeling experiments. 相似文献
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Promoting the Hydrosilylation of Benzaldehyde by Using a Dicationic Antimony‐Based Lewis Acid: Evidence for the Double Electrophilic Activation of the Carbonyl Substrate 下载免费PDF全文
Masato Hirai Junsang Cho Prof. Dr. François P. Gabbaï 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6537-6541
The concomitant activation of carbonyl substrates by two Lewis acids has been investigated by using [1,2‐(Ph2MeSb)2C6H4]2+ ([ 1 ]2+), an antimony‐based bidentate Lewis acid obtained by methylation of the corresponding distibine. Unlike the simple stibonium cation [Ph3MeSb]+, dication [ 1 ]2+ efficiently catalyzes the hydrosilylation of benzaldehyde under mild conditions. The catalytic activity of this dication is correlated to its ability to doubly activate the carbonyl functionality of the organic substrate. This view is supported by the isolation of [ 1 ‐μ2‐DMF][OTf]2, an adduct, in which the DMF oxygen atom bridges the two antimony centers. 相似文献
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Molecular Precursors for the Phase‐Change Material Germanium‐Antimony‐Telluride,Ge2Sb2Te5 (GST) 下载免费PDF全文
Nicole Harmgarth Florian Zörner Phil Liebing Edmund P. Burte Mindaugas Silinskas Felix Engelhardt Frank T. Edelmann 《无机化学与普通化学杂志》2017,643(18):1150-1166
This review provides an overview of the precursor chemistry that has been developed around the phase‐change material germanium‐antimony‐telluride, Ge2Sb2Te5 (GST). Thin films of GST can be deposited by employing either chemical vapor deposition (CVD) or atomic layer deposition (ALD) techniques. In both cases, the success of the layer deposition crucially depends on the proper choice of suitable molecular precursors. Previously reported processes mainly relied on simple alkoxides, alkyls, amides and halides of germanium, antimony, and tellurium. More sophisticated precursor design provided a number of promising new aziridinides and guanidinates. 相似文献