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101.
Zhu XH Mercier N Frère P Blanchard P Roncali J Allain M Pasquier C Riou A 《Inorganic chemistry》2003,42(17):5330-5339
2,2'-bithiophene derivatives, 5-ammoniumethylsulfanyl-2,2'-bithiophene (AESBT) and 5,5'-bis(ammoniumethylsulfanyl)-2,2'-bithiophene (BAESBT), have been designed for their incorporation in organic-inorganic materials based on iodometalates. Three layered compounds, (BAESBT)PbI(4), (AESBT)(4)Pb(3)I(10), and (AESBT)(3)Bi(2)I(9), have been synthesized as crystals from slowly cooled aqueous solution containing metal halide and bithiophene derivative salts. When starting from the diammonium cation, (BAESBT)PbI(4) hybrid perovskite is obtained. (BAESBT)PbI(4) adopts a triclinic cell (P1) with the lattice parameters a = 8.4741(5) A, b = 8.9255(6) A, c = 16.876(1) A, alpha = 88.328(5) degrees, beta = 81.806(4) degrees, gamma = 88.864(5) degrees, Z = 2. In the structure, PbI(4)(2)(-) perovskite sheets and diammonium cation layers alternate along c. The incorporation of the corresponding monoammonium cation (AESBT) leads to a head to tail arrangement of the molecules in the (AESBT)(4)Pb(3)I(10) hybrid, precluding the formation of the perovskite layers. (AESBT)(4)Pb(3)I(10) is orthorhombic, Pna2(1), with a = 38.333(4) A, b = 22.239(3) A, c = 8.448(2) A, Z = 4. The structure consists of corrugated layers of Pb(3)I(10)(4)(-) separated by organic layers of monoammonium cations. A similar relative situation of molecules in organic layers is observed in (AESBT)(3)Bi(2)I(9), with the inorganic sheets being built up from Bi(2)I(9)(3)(-) entities. (AESBT)(3)Bi(2)I(9) crystallizes in an orthorhombic cell (P2(1)2(1)2(1)) with a = 8.4564(6) A, b = 21.368(2) A, c = 30.747(2) A, Z = 4. In the three compounds, the molecular packings appear different, underlining the interplay between both organic and inorganic components. New packings are stabilized, as illustrated by an original mixed kappa-alpha type arrangement of the bithiophene units in (AESBT)(3)Bi(2)I(9). Furthermore, molecular interactions, especially of S.S type, appear stronger in the hybrids based on the monoammonium cations. The electrical conductivity of a (BAESBT)PbI(4) single crystal has also been investigated, revealing a semiconductive behavior with a characteristic energy of E(g) = 2.535 eV. 相似文献
102.
A total synthesis of the naturally occurring ionophore zincophorin has been realized. The route features an intramolecular oxymercuration of a cyclopropanemethanol and a Carroll-Claisen rearrangement for the respective elaboration of the C1-C12 and C13-C25 subunits, which have been assembled by using a highly diastereoselective titanium-mediated aldol condensation. 相似文献
103.
Alexandre Dmitriev Hannes Spillmann Sebastian Stepanow Thomas Strunskus Christof W?ll Ari P Seitsonen Magali Lingenfelder Nian Lin Johannes V Barth Klaus Kern 《Chemphyschem》2006,7(10):2197-2204
The mesoscale induction of two-dimensional supramolecular chirality (formation of 2D organic domains with a single handedness) was achieved by self-assembly of 1,2,4-benzenetricarboxylic (trimellitic) acid on a Cu(100) surface at elevated temperatures. The combination of spectroscopic [X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS)], real-space-probe [scanning tunneling microscopy (STM)], and computational [density functional theory (DFT)] methods allows a comprehensive characterization of the obtained organic adlayers, where details of molecular adsorption geometry, intermolecular coupling, and surface chemical bonding are elucidated. The trimellitic acid species, comprising three functional carboxylic groups, form distinct stable mirror-symmetric hydrogen-bonded domains. The chiral ordering is associated with conformational restriction in the domains: molecules anchor to the substrate with an ortho carboxylate group, providing two para carboxylic acid moieties for collective lateral interweaving through H bonding, which induces a specific tilt of the molecular plane. The ease of molecular symmetry switching in domain formation makes homochiral-signature propagation solely limited by the terrace width. The molecular layer modifies the morphology of the underlying copper substrate and induces mum-sized strictly homochiral terraces. 相似文献
104.
Emad Aqad Philippe Leriche Gilles MabonAlain Gorgues Magali AllainAmédée Riou Arkady EllernVladimir Khodorkovsky 《Tetrahedron》2003,59(30):5773-5782
A series of proaromatic electron acceptors derived from fulvenes were synthesized from tetrachlorocyclopentadiene and previously unknown 1,4-dicyano- and 1,4-dialkoxycarbonyl-2,3-dimethoxy cyclopentadienes. Two reversible one-electron reductions steps observed for fulvalenes coalesce into one two-electron reduction step upon increasing the length of the conjugating bridge. 相似文献
105.
Bismuth‐Based Coordination Polymers with Efficient Aggregation‐Induced Phosphorescence and Reversible Mechanochromic Luminescence 下载免费PDF全文
Dr. Oksana Toma Magali Allain Dr. Francesco Meinardi Dr. Alessandra Forni Dr. Chiara Botta Prof. Nicolas Mercier 《Angewandte Chemie (International ed. in English)》2016,55(28):7998-8002
Two bismuth coordination polymers (CPs), (TBA)[BiBr4(bp4mo)] (TBA=tetrabutylammonium) and [BiBr3(bp4mo)2], which are based on the rarely used simple ditopic ligand N‐oxide‐4,4′‐bipyridine (bp4mo), show mechanochromic luminescence (MCL). High solid‐state phosphorescence quantum yields of up to 85 % were determined for (TBA)[BiBr4(bp4mo)] (λem=540 nm). Thorough investigations of the luminescence properties combined with DFT and TDDFT calculations revealed that the emission is due to aggregation‐induced phosphorescence (AIP). Upon grinding, both samples became amorphous, and their luminescence changed from yellow to orange and red, respectively. Heating or exposure to water vapor led to the recovery of the initial luminescence. These materials are the first examples of mechanochromic phosphors based on bismuth(III). 相似文献
106.
Eloisa Ríos Magali Hernández Ilich A. Ibarra Ariel Guzmán Enrique Lima 《Chemistry Central journal》2016,10(1):68
Samples of layered double hydroxides were prepared by a sol–gel procedure. Quinolinate Al(C9H6NO)3 units were added during the synthesis, leading to composite quinolinate hydrotalcite-like compounds. The amount of quinolinate was varied, showing that the number of organic building blocks determines the physicochemical properties of materials, which differ significantly from those commonly reported for hydrotalcites without any quinolinate. The order of layers, specific surface area and coordination of aluminium were the parameters most significantly influenced by the presence of the quinolinate as a part of the brucite-like layers. The composite quinolinate-hydrotalcite materials were tested to catalyse the Kabachnik–Fields reaction.
相似文献
107.
Henrique Peres Araújo Juliana Silva Flix Jos Eduardo Manzoli Marisa Padula Magali Monteiro 《Radiation Physics and Chemistry》2008,77(7):913-917
A gas chromatographic method to determine caprolactam in multilayer PA-6 films used for meat foodstuffs and cheese was developed and validated. A wide linear range (0.8–400 μg/ml), RSD4.1% and recovery higher than 90.0% were obtained for the chromatographic system, while precision and accuracy of the method showed RSD3.8%, recovery from 95.5–100.0% and LOQ of 32 μg/g. Irradiated (3, 7 and 12 kGy) and non-irradiated commercial films were analyzed. Most of them increased caprolactam levels with the increase of irradiation doses. 相似文献
108.
[structure: see text] The reaction of 2,5-diphenylphospholide, first with acyl chlorides, then with tBuOK, provides a direct access to 3-acyl-2,5-diphenylphospholides via a 1H-, 2H-, 3H-phosphole equilibrium. 相似文献
109.
110.
Crystal engineering of pharmaceutical co-crystals from polymorphic active pharmaceutical ingredients 总被引:2,自引:0,他引:2
Vishweshwar P McMahon JA Peterson ML Hickey MB Shattock TR Zaworotko MJ 《Chemical communications (Cambridge, England)》2005,(36):4601-4603
The carboxylic acid-primary amide supramolecular heterosynthon is exploited for the generation of pharmaceutical co-crystals that contain two active pharmaceutical ingredients that are polymorphic in their pure forms. 相似文献