Rados&#x;aw Kotuniak  Marc J. F. Strampraad  Karolina Bossak‐Ahmad  Urszula E. Wawrzyniak  Iwona Ufnalska  Peter‐Leon Hagedoorn  Wojciech Bal 《Angewandte Chemie (International ed. in English)》2020,59(28)

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Chengyi Wang  Zihe Zhang  Weiwei Liu  Qinming Zhang  Xin‐Gai Wang  Zhaojun Xie  Zhen Zhou 《Angewandte Chemie (International ed. in English)》2020,59(41)

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Li‐Ming Zhao  Xia‐Qiang Shen  Qian Liu  Wei Wu  Hao‐Hong Li  Zhi‐Rong Chen  Yi Li 《化学:亚洲杂志》2020,15(1):136-147

Host‐guest encapsulation of functional organic dye into a porous metal‐organic framework can give rise to the development of new functional materials. In this work, by intercalating the stilbazolium‐type dye (DEAST)I (4′‐diethylamino‐N‐methyl stilbazolium) into four lanthanide layered metal‐organic complexes (Ln‐LMOCs), i. e. {[Ln(BTB)(H₂O)₂]?3(DMF)?2(H₂O)}_n (Ln=La (1), Nd (2), Sm (3), Er (4)), four responsive (DEAST)I@Ln‐LMOC composites have been prepared, serving as multifunctional performance platform. The core–shell structures of (DEAST)I@Ln‐LMOC composites have been fully characterized by IR, UV/Vis, PXRD, SEM, TEM, TGA and ESR. Significantly, after intercalation of dyes, the (DEAST)I@Ln‐LMOC composites exhibit enhanced luminescent sensing properties in detecting Fe³⁺ with much higher water stabilities. The luminescent sensing behavior stems from the fluorescence resonance energy transfer (FRET) from the π‐electron‐rich BTB ligands to the Fe³⁺, and their higher water stabilities are induced by electrostatic interactions and lower porosity. Specially, the characteristic emissions of Sm³⁺ will not be affected after the encapsulation guest dyes, which provide a theoretical guide for the modulation of luminescence devices. Finally, better ion conductivities and diminished photocurrents can be achieved after the embedding of the functional organic dye. In all, the formation of (DEAST)I@Ln‐LMOC composites with core–shell structures can be utilized as a multifunctional platform with good stability.  相似文献   

    

Xing‐Cai Huang  Jia‐Xin Li  Yong‐Zhi Chen  Wen‐Yan Wang  Rui Xu  Jin‐Xia Tao  Dong Shao  Yi‐Quan Zhang 《化学:亚洲杂志》2020,15(9):1469-1477

Tuning the magnetic anisotropy of metal ions remains highly interesting in the design of improved single‐molecule magnets (SMMs). We herein report synthetic, structural, magnetic, and computational studies of four mononuclear Co^II complexes, namely [Co(hfac)₂(MeCN)₂] ( 1 ), [Co(hfac)₂(Spy)₂] ( 2 ), [Co(hfac)₂(MBIm)₂] ( 3 ), and [Co(hfac)₂(DMF)₂] ( 4 ) (MeCN=acetonitrile, hfac=hexafluoroacetylacetone, Spy=4‐styrylpyridine, MbIm=5,6‐dimethylbenzimidazole, DMF=N,N‐dimethylformamide), with distorted octahedral geometry constructed from hexafluoroacetylacetone (hfac) and various axial ligands. By a building block approach, complexes 2 – 4 were synthesized by recrystallization of the starting material of 1 from various ligands containing solution. Magnetic and theoretical studies reveal that 1 – 4 possess large positive D values and relative small E parameters, indicating easy‐plane magnetic anisotropy with significant rhombic anisotropy in 1 – 4 . Dynamic alternative current (ac) magnetic susceptibility measurements indicate that these complexes exhibit slow magnetic relaxation under external fields, suggesting field‐induced single‐ion magnets (SIMs) of 1 – 4 . These results provide a promising platform to achieve fine tuning of magnetic anisotropy through varying the axial ligands based on Co(II) bis(hexafluoroacetylacetonate) complexes.  相似文献   

    

Junya Adachi  Taizo Mori  Ryo Inoue  Masaya Naito  Ngoc Ha‐Thu Le  Soichiro Kawamorita  Jonathan P. Hill  Takeshi Naota  Katsuhiko Ariga 《化学:亚洲杂志》2020,15(3):406-414

Molecular functions depend on conformations and motions of the corresponding molecular species. An air–water interface is a suitable asymmetric field for the control of molecular conformations and motions under a small applied force. In this work, double‐paddled binuclear Pt^II complexes containing pyrazole rings linked by alkyl spacers were synthesized and their orientations and emission properties dynamically manipulated at the air–water interface. The complexes emerge from water with concurrent variation of interface orientation of the planes of the Pt^II complexes from perpendicular to parallel during mechanical compression suggesting a unique ‘submarine emission‘. Phosphorescence of the complexes is quenched at the air–water interface prior to monolayer formation with intensities subsequently rapidly increasing during monolayer compression. These results indicate that asymmetric reactions and motions might be controlled by applying mechanical force at the air–water interface.  相似文献   

    

Biswarup Chakraborty  Shweta Kalra  Rodrigo Beltrn‐Suito  Chittaranjan Das  Tim Hellmann  Prashanth W. Menezes  Matthias Driess 《化学:亚洲杂志》2020,15(6):852-859

In the urge of designing noble metal‐free and sustainable electrocatalysts for oxygen evolution reaction (OER), herein, a mineral Digenite Cu₉S₅ has been prepared from a molecular copper(I) precursor, [{(PyHS)₂Cu^I(PyHS)}₂](OTf)₂ ( 1 ), and utilized as an anode material in electrocatalytic OER for the first time. A hot injection of 1 yielded a pure phase and highly crystalline Cu₉S₅, which was then electrophoretically deposited (EPD) on a highly conducting nickel foam (NF) substrate. When assessed as an electrode for OER, the Cu₉S₅/NF displayed an overpotential of merely 298±3 mV at a current density of 10 mA cm^?2 in alkaline media. The overpotential recorded here supersedes the value obtained for the best reported Cu‐based as well as the benchmark precious‐metal‐based RuO₂ and IrO₂ electrocatalysts. In addition, the choronoamperometric OER indicated the superior stability of Cu₉S₅/NF, rendering its suitability as the sustainable anode material for practical feasibility. The excellent catalytic activity of Cu₉S₅ can be attributed to the formation of a crystalline CuO overlayer on the conductive Cu₉S₅ that behaves as active species to facilitate OER. This study delivers a distinct molecular precursor approach to produce highly active copper‐based catalysts that could be used as an efficient and durable OER electro(pre)catalysts relying on non‐precious metals.  相似文献   

    

Jun Ying  Qian Gao  Xiao‐Feng Wu 《化学:亚洲杂志》2020,15(10):1540-1543

We have developed a facile and efficient procedure for the synthesis of diarylphosphate esters and amides. Using Zn(acac)₂ as the catalyst, the reaction of diarylphosphoryl azides with aliphatic alcohols and phenols through an unusual P?N bond cleavage provided a number of diarylphosphate esters in good yields (22 examples, up to 94%). Additionally, various diarylphosphate amides were obtained from the corresponding amines in excellent yields as well (8 examples, up to 96%).  相似文献   

    

Fahime Bigdeli  Christina T. Lollar  Ali Morsali  Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2020,59(12):4652-4669

In recent years, metal–organic frameworks (MOFs) have become an area of intense research interest because of their adjustable pores and nearly limitless structural diversity deriving from the design of different organic linkers and metal structural building units (SBUs). Among the recent great challenges for scientists include switchable MOFs and their corresponding applications. Switchable MOFs are a type of smart material that undergo distinct, reversible, chemical changes in their structure upon exposure to external stimuli, yielding interesting technological applicability. Although the process of switching shares similarities with flexibility, very limited studies have been devoted specifically to switching, while a fairly large amount of research and a number of Reviews have covered flexibility in MOFs. This Review focuses on the properties and general design of switchable MOFs. The switching activity has been delineated based on the cause of the switching: light, spin crossover (SCO), redox, temperature, and wettability.  相似文献   

    

Anthony Jolly  Dandan Miao  Maxime Daigle  Jean‐Franois Morin 《Angewandte Chemie (International ed. in English)》2020,59(12):4624-4633

The solution‐phase synthesis is one of the most promising strategies for the preparation of well‐defined graphene nanoribbons (GNRs) in large scale. To prepare high quality, defect‐free GNRs, cycloaromatization reactions need to be very efficient, proceed without side reaction and mild enough to accommodate the presence of various functional groups. In this Minireview, we present the latest synthetic approaches for the synthesis of GNRs and related structures, including alkyne benzannulation, photochemical cyclodehydrohalogenation, Mallory and Pd‐ and Ni‐catalyzed reactions.  相似文献   

    

Hideyuki Tatsuno  Kasper S. Kjr  Kristjan Kunnus  Tobias C. B. Harlang  Cornelia Timm  Meiyuan Guo  Pavel Chbera  Lisa A. Fredin  Robert W. Hartsock  Marco E. Reinhard  Sergey Koroidov  Lin Li  Amy A. Cordones  Olga Gordivska  Om Prakash  Yizhu Liu  Mads G. Laursen  Elisa Biasin  Frederik B. Hansen  Peter Vester  Morten Christensen  Kristoffer Haldrup  Zoltn Nmeth  Dorottya Srosin Szemes  va Bajnczi  Gyrgy Vank  Tim B. Van Driel  Roberto Alonso‐Mori  James M. Glownia  Silke Nelson  Marcin Sikorski  Henrik T. Lemke  Dimosthenis Sokaras  Sophie E. Canton  Asmus O. Dohn  Klaus B. Mller  Martin M. Nielsen  Kelly J. Gaffney  Kenneth Wrnmark  Villy Sundstrm  Petter Persson  Jens Uhlig 《Angewandte Chemie (International ed. in English)》2020,59(1):364-372

Iron N‐heterocyclic carbene (NHC) complexes have received a great deal of attention recently because of their growing potential as light sensitizers or photocatalysts. We present a sub‐ps X‐ray spectroscopy study of an Fe^IINHC complex that identifies and quantifies the states involved in the deactivation cascade after light absorption. Excited molecules relax back to the ground state along two pathways: After population of a hot ³MLCT state, from the initially excited ¹MLCT state, 30 % of the molecules undergo ultrafast (150 fs) relaxation to the ³MC state, in competition with vibrational relaxation and cooling to the relaxed ³MLCT state. The relaxed ³MLCT state then decays much more slowly (7.6 ps) to the ³MC state. The ³MC state is rapidly (2.2 ps) deactivated to the ground state. The ⁵MC state is not involved in the deactivation pathway. The ultrafast partial deactivation of the ³MLCT state constitutes a loss channel from the point of view of photochemical efficiency and highlights the necessity to screen transition‐metal complexes for similar ultrafast decays to optimize photochemical performance.  相似文献