Andreas J. Hofmann;Christian Jandl;Corinna R. Hess; 《欧洲无机化学杂志》2020,2020(5):499-505

We present two bimetallic iron complexes, [Fe2(PDIeCy)(OTf)4] (1) and [Fe2(PDIpCy)(THF)(OTf)4] (2) coordinated by an unsymmetric ligand. The new ligand, PDIeCy (PDI = pyridyldiimine; e = ethyl; Cy = cyclam), is a variant of the previously reported PDIpCy (p = propyl) ligand, featuring a shorter linker between the two metal coordination sites. The structural and electronic properties of 1 and 2, both in the solid and solution state, were analyzed by means of X-ray crystallography, and spectroscopic methods, including 19F-NMR. The two ligand platforms yield markedly different diiron structures: the PDIeCy ligand permits formation of a bridged, µ-OTf complex, while the two iron centers of the PDIpCy-based 2 remain unconnected, directly, under all conditions examined. Both compounds contain electronically non-coupled high-spin (S = 2) ferrous centers, as established by Mössbauer spectroscopy and magnetic susceptibility studies. Cyclic voltammetry demonstrates the rich redox chemistry of the compounds, involving both ligand and metal-centered redox processes. Moreover, we synthesized the two-electron reduced [Fe2(PDIeCy)]2+ form of 1, which contains the dianionic PDI2– ligand, and represents a two-electron charge localized complex.  相似文献   

    

Dr. Jens Voskuhl  Dr. Christian Wendeln  M. Sc. Frank Versluis  M. Sc. Eva‐Corinna Fritz  M. Sc. Oliver Roling  M. Sc. Harshal Zope  Dr. Christian Schulz  Dipl.‐Phys. Stefan Rinnen  Prof. Dr. Heinrich F. Arlinghaus  Prof. Dr. Bart Jan Ravoo  Dr. Alexander Kros 《Angewandte Chemie (International ed. in English)》2012,51(50):12616-12620

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Herbert M. Riepl  Corinna Urmann 《Helvetica chimica acta》2012,95(8):1461-1477

Indirubin, present in extracts of Isatis tinctoria and some other plant species, has promising cytotoxicity against a variety of cell lines by inhibition of cyclin‐dependent kinases. Chemical synthesis of its derivatives relies on the combination of isatins and 2,3‐dihydro‐1H‐indol‐3‐one (‘indoxyl’) derivatives and usually yields indigo as well as other by‐products. Inspection of the hydrolysis of the long‐known condensation products of 2‐thioxothiazolidin‐4‐one with isatins gave useful hints for an improved synthesis of indirubins: this reaction does not yield quinoline derivatives but 2‐(2,3‐dihydro‐2‐oxo‐1H‐indol‐3‐ylidene)‐2‐sulfanyl acetic acids. By substitution of the sulfanyl group in this oxindoles with anilines and straightforward cyclization under Nazarov conditions, a broad variety of indirubins substituted in the indoxyl ring system are thus available, usually in very good purity and yield. Use of naphthylamines in this reaction sequence yields various fluorescent substances with λ_fl at ca. 630 nm.  相似文献   

    

Riccardo Cribiú  Corinna Jger  Cristina Nevado 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2009,121(46):8938-8941

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Corinna S. Schindler  Stefan Diethelm  Erick M. Carreira Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(34):6296-6299

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Corinna Sieke  Ingo Hartenbach  Thomas Schleid 《无机化学与普通化学杂志》2000,626(10):2235-2239

On the Dimorphism of Nd₃Cl[SiO₄]₂ On reacting NdCl₃, Nd₂O₃, and SiO₂ (molar ratio: 1 : 4 : 6) at 850 °C in evacuated silica tubes, pale violet, hydrolysis resistant neodymium(III) chloride ortho‐silicate Nd₃Cl[SiO₄]₂ can be obtained within seven days. If equimolar amounts of NaCl are added as flux, rod‐ or platelet‐shaped, transparent single crystals of two modifications accumulate simultaneously. The one with the higher density (A‐Nd₃Cl[SiO₄]₂) crystallizes monoclinically (C2/c, no. 15; a = 1416.6(1), b = 638.79(6), c = 872.21(9) pm, β = 98.403(7)°; V_m = 117.55 cm³/mol, Z = 4), whereas the one with the lower density (B‐Nd₃Cl[SiO₄]₂) exhibits orthorhombic symmetry (Pnma, no. 62; a = 709.36(7), b = 1815.7(2), c = 631.48(6) pm; V_m = 122.45 cm³/mol, Z = 4). Two crystallographically independent Nd³⁺ cations exist in each of both crystal structures, which in the A type are surrounded by nine (1 Cl^– + 8 O^2–) and ten (2 Cl^– + 8 O^2–), whilst those in the B type by only two times eight (1 Cl^– + 7 O^2– and 2 Cl^– + 6 O^2–) anions, respectively. Thereby all oxygen atoms of both forms represent members of discrete ortho‐silicate tetrahedra ([SiO₄]^4–). Although both crystal structures are built of alternating anionic double layers {(Nd1)₂[SiO₄]₂}^2– and cationic single layers {(Nd2)Cl}²⁺, there is a higher cross‐linkage of the building units in the A‐type lattice, where the cations are coordinated by three and four tetrahedra edges of ortho‐silicate anions, compared to only two times two of them in the B type. From this an about 4% higher density of Nd₃Cl[SiO₄]₂ results for the A‐type structure (D_x = 5.55 g/cm³) in comparison with B‐type Nd₃Cl[SiO₄]₂ (D_x = 5.33 g/cm³).  相似文献   

    

Marco Esters  Matti B. Alemayehu  Zachary Jones  Dr. N. T. Nguyen  Dr. Michael D. Anderson  Corinna Grosse  Prof. Saskia F. Fischer  Prof. David C. Johnson 《Angewandte Chemie (International ed. in English)》2015,54(4)

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Hendrik Frisch  Eva‐Corinna Fritz  Friedrich Stricker  Lars Schmüser  Daniel Spitzer  Dr. Tobias Weidner  Prof. Dr. Bart Jan Ravoo  Prof. Dr. Pol Besenius 《Angewandte Chemie (International ed. in English)》2016,55(25):7242-7246

We report a facile strategy to grow supramolecular copolymers on Au surfaces by successively exposing a surface‐anchored monomer to solutions of oppositely charged peptide comonomers. Charge regulation on the active chain end of the polymer sufficiently slows down the kinetics of the self‐assembly process to produce kinetically trapped copolymers at near‐neutral pH. We thereby achieve architectural control at three levels: The β‐sheet sequences direct the polymerization away from the surface, the height of the supramolecular copolymer brushes is well‐controlled by the stepwise nature of the alternating copolymer growth, and 2D spatial resolution is realized by using micropatterned initiating monomers. The programmable nature of the resulting architectures renders this concept attractive for the development of customized biomaterials or chiral interfaces for optoelectronics and sensor applications.  相似文献   

    

Corinna Lorenz  Florian Hastreiter  Dr. Johnny Hioe  Dr. N. Lokesh  Dr. Stefanie Gärtner  Prof. Dr. Nikolaus Korber  Prof. Dr. Ruth M. Gschwind 《Angewandte Chemie (International ed. in English)》2018,57(39):12956-12960

We report on the first unambiguous detection of the elusive [HSi₉]^3? anion in solutions of liquid ammonia by various ²⁹Si and ¹H NMR experiments including chemical exchange saturation transfer (CEST). The characteristic multiplicity patterns of both the ²⁹Si and ¹H resonances together with CEST and a partially reduced ¹H,²⁹Si coupling constant indicate the presence of a highly dynamic Si₈ entity and a Si?H moiety with slow proton hopping. Theoretical calculations corroborate both reorganization of Si₈ on the picosecond timescale via low vibrational modes and proton hopping. In addition, in a single‐crystal X‐ray study of (K(DB[18]crown‐6))(K([2.2.2]crypt))₂[ HSi₉ ]?8.5 NH₃, the H atom was unequivocally localized at one vertex of the basal square of the monocapped square‐antiprismatic cluster. Thus experimental studies and theoretical considerations provide unprecedented insight into both the structure and the dynamic behavior of these cluster anions, which hitherto had been considered to be rigid.  相似文献   

Fra Angelico’s painting technique revealed by terahertz time-domain imaging (THz-TDI)     

Corinna Ludovica Koch Dandolo  Marcello Picollo  Costanza Cucci  Peter Uhd Jepsen 《Applied Physics A: Materials Science & Processing》2016,122(10):898

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