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1.
P. Thuéry M. Nierlich Z. Asfari J. Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》1997,27(2):169-178
The crystal structures of a new solvate of the ditopic receptor 1,3-calix[4]-bis-crown-6, Bis-C6, and of 1,3-calix[4]-bis-(benzo-crown-6), Bis-benzoC6, are reported. Bis-C6.3 CH3CN (1) crystallizes in the monoclinic space group P21/n, a = 14.388(3), b = 26.947(8), c = 14.707(4) Å, = 113.19(3)°, V = 5241(5) Å3, Z = 4. Refinement led to a final conventional R value of 0.092 for 2723 reflections. The structure of (1) differs from the previously reported structure of Bis-C6.4 CH3CN by the conformation of one crown either chain. Two acetonitrile molecules are in the close neighbourhood of the crown ether cavities. Bis-benzoC6.3 CH3CN (2) crystallizes in the monoclinic space group P21/c, a = 10.391(4), b = 17.264(11), c = 30.426(9) Å, = 94.62(3)°, V = 5440(7) Å3, Z = 4. Refinement led to a final conventional R value of 0.106 for 2965 reflections. Two acetonitrile molecules are located near the crown ether cavities, as in (1). One of the crown ether conformations is the same as in the binuclear caesium complex of Bis-benzoC6, supporting the hypothesis of a preorganization of this ligand towards the complexation of this ion; the second crown ether chain is partially disordered. 相似文献
2.
Jean BourguignonUlf Bremberg Georges DupasKristina Hallman Lars HagbergLaurent Hortala Vincent LevacherSerghey Lutsenko Emmanuel MacedoChristina Moberg Guy QuéguinerFredrik Rahm 《Tetrahedron》2003,59(48):9583-9589
Chiral pyridinooxazoline, quinolinooxazoline, bis(oxazolino)pyridine (pybox), and bisoxazoline (box) derivatives containing crown ether residues were prepared. Some of the ligands were assessed in substrate binding studies and in palladium catalyzed allylic alkylations. 相似文献
3.
P. Thuéry M. Nierlich C. Bressot V. Lamare J. F. Dozol Z. Asfari J. Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》1995,23(4):305-312
The crystal structures of two binuclear complexes between caesium and 1,3-calix[4]-bis-crowns have been determined. Cs2
Bis-benzoC6(NO3)2. 3CHCl3 (1) in whichBis-benzoC6 is 1,3-calix[4]-bis-benzo-crown-6, crystallizes in the orthorhombic system: space groupPca2
1 a=19.513(10),b=15.382(5),c=23.708(9) Å,V=7116(5) Å3,Z=4. Refinement led to a final conventionalR value of 0.065 for 2321 reflections. The structure of (1) is analogous to those already reported withBis-C6, (in whichBis-C6 is, 1,3-calix[4]-bis-crown-6) and NO
3
–
as a counter-ion. Cs2
Bis-C6(NCS)2 (2) crystallizes in the monoclinic system: space, groupC2 a=36.57(2),b=11.47(1),c=13.65(1) Å, =109.03(5)°.,V=5415(6) Å3,Z=4. Refinement led to a final conventionalR value of 0.063 for 2227 reflections. Compound (2) is made of dimers bridged by a disordered NCS– ion. The crown ether chain conformations are discussed.
Supplementary data relating to this article (atomic coordinates, anisotropic displacement parameters, bond distances and angles and observed and calculated structure factors) are deposited with the British Library as Supplementary Publication No. SUP 82199 (52 pages). 相似文献
4.
Lipiao Bao Baolin Zhao Vicent Lloret Marcus Halik Frank Hauke Andreas Hirsch 《Angewandte Chemie (International ed. in English)》2020,59(17):6700-6705
Patterned functionalization can, on the one hand, open the band gap of graphene and, on the other hand, program demanding designs on graphene. The functionalization technique is essential for graphene‐based nanoarchitectures. A new and highly efficient method was applied to obtain patterned functionalization on graphene by mild fluorination with spatially arranged AgF arrays on the structured substrate. Scanning Raman spectroscopy (SRS) and scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy (SEM‐EDS) were used to characterize the functionalized materials. For the first time, chemical patterning on the bottom side of graphene was realized. The chemical nature of the patterned functionalization was determined to be the ditopic scenario with fluorine atoms occupying the bottom side and moieties, such as oxygen‐containing groups or hydrogen atoms, binding on the top side, which provides information about the mechanism of the fluorination process. Our strategy can be conceptually extended to pattern other functionalities by using other reactants. Bottom‐side patterned functionalization enables utilization of the top side of a material, thereby opening up the possibilities for applications in graphene‐based devices. 相似文献
5.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(9):724-730
3‐(Pyridin‐4‐yl)acetylacetone (HacacPy) acts as a pyridine‐type ligand towards CdII and HgII halides. With CdBr2, the one‐dimensional polymer [Cd(μ‐Br)2(HacacPy)Cd(μ‐Br)2(HacacPy)2]∞ is obtained in which five‐ and six‐coordinated CdII cations alternate in the chain direction. Reaction of HacacPy with HgBr2 results in [Hg(μ‐Br)Br(HacacPy)]∞, a polymer in which each HgII centre is tetracoordinated. In both compounds, each metal(II) cation is N‐coordinated by at least one HacacPy ligand. Equimolar reaction between these CdII and HgII derivatives, either conducted in ethanol as solvent or via grinding in the solid state, leads to ligand redistribution and the formation of the well‐ordered bimetallic polymer catena‐poly[[bromidomercury(II)]‐μ‐bromido‐[aquabis[4‐hydroxy‐3‐(pyridin‐4‐yl)pent‐3‐en‐2‐one]cadmium(II)]‐di‐μ‐bromido], [CdHgBr4(C10H11NO2)2(H2O)]n or [{HgBr}(μ‐Br){(HacacPy)2Cd(H2O)}(μ‐Br)2]∞. HgII and CdII cations alternate in the [100] direction. The HacacPy ligands do not bind to the HgII cations, which are tetracoordinated by three bridging and one terminal bromide ligand. The CdII centres adopt an only slightly distorted octahedral coordination. Three bromide ligands link them in a (2 + 1) pattern to neighbouring HgII atoms; two HacacPy ligands in a cis configuration, acting as N‐atom donors, and a terminal aqua ligand complete the coordination sphere. Classical O—H…Br hydrogen bonds stabilize the polymeric chain. O—H…O hydrogen bonds between aqua H atoms and the uncoordinated carbonyl group of an HacacPy ligand in a neighbouring strand in the c direction link the chains into layers in the (010) plane. 相似文献
6.
7.
Pierre Thuéry Martine Nierlich Éronique Lamare Jean-François Dozol Zouhair Asfari Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2000,36(4):375-408
The association within one molecule ofcalix[4]arene and crown ether moieties leads toligands with new complexing properties. In particular,calix[4]arene bis(crown-6) and some of itsderivatives have been shown to be highly selectiveextractants for caesium ions. This review presents thebackground of the study and the results of crystalstructure determinations and molecular modellingcalculations performed during the investigation of twomolecular families, the bis(crown ether) and theazobenzocrown derivatives of calix[4]arene. 相似文献
8.
Dr. Lipiao Bao Baolin Zhao Vicent Lloret Prof. Dr. Marcus Halik Dr. Frank Hauke Prof. Dr. Andreas Hirsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6766-6771
Patterned functionalization can, on the one hand, open the band gap of graphene and, on the other hand, program demanding designs on graphene. The functionalization technique is essential for graphene-based nanoarchitectures. A new and highly efficient method was applied to obtain patterned functionalization on graphene by mild fluorination with spatially arranged AgF arrays on the structured substrate. Scanning Raman spectroscopy (SRS) and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) were used to characterize the functionalized materials. For the first time, chemical patterning on the bottom side of graphene was realized. The chemical nature of the patterned functionalization was determined to be the ditopic scenario with fluorine atoms occupying the bottom side and moieties, such as oxygen-containing groups or hydrogen atoms, binding on the top side, which provides information about the mechanism of the fluorination process. Our strategy can be conceptually extended to pattern other functionalities by using other reactants. Bottom-side patterned functionalization enables utilization of the top side of a material, thereby opening up the possibilities for applications in graphene-based devices. 相似文献
9.
An easy‐to‐run route to a new ditopic ligand possessing linear and cyclic tetraaza subunits is described. In the first step, the reaction consists in the preparation of a triprotected cyclam bearing a 3‐bromopropyl pendant side chain. A subsequent reaction with a bisaminal protected linear tetraamine gives, after deprotection, the desired ditopic ligand. 相似文献
10.
Olga Fedorova Elena Lukovskaya Artem Mizerev Yury Fedorov Alla Bobylyova Anton Maksimov Anna Moiseeva Aleksander Anisimov Gediminas Jonusauskas 《Journal of Physical Organic Chemistry》2010,23(3):246-254
A novel ditopic receptor was constructed as a combination of bisthiophene with pyridinylvinyl and crown‐containing styryl fragments. In the receptor, the pyridine residue was able to coordinate Fe2+, Cd2+, and Mg2+ metal cations, whereas the oxocrown ether moiety bound with the alkaline earth metal (Mg2+, Ca2+, and Ba2+) cations. 1H NMR, optical, electrochemical, and ESI‐MS results provided conclusive evidence of a complex formation through both the coordination centers of the molecule. The obtained results showed that cation complexation induces optical and electrochemical changes, particularly for each binding center. This type of multiparameter sensor provides interesting perspectives for the future design of unique sensors, promising different analytical techniques. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献