排序方式: 共有61条查询结果,搜索用时 15 毫秒
41.
Dr. Thomas Biet Arnaud Fihey Dr. Thomas Cauchy Dr. Nicolas Vanthuyne Prof. Christian Roussel Dr. Jeanne Crassous Dr. Narcis Avarvari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(39):13160-13167
Electroactive fused ethylenedithio? tetrathiafulvalene? [4]helicene and ‐[6]helicenes have been synthesized through a strategy that involved the preparation of 2,3‐dibromo‐helicene derivatives as intermediates. The dihedral angles between the terminal helicenes, as determined by single‐crystal X‐ray analysis, are 22.7° and 50.7° for the [4]helicene and [6]helicene, respectively. Their solid‐state architectures show interplay between S???S and π???π intermolecular interactions. The chiroptical properties of the enantiopure EDT? TTF? [6]helicene derivatives have been investigated and supported by TDDFT calculations. Remarkable redox switching of the circular dichroism (CD) signal between the neutral and radical‐cation species has been achieved. 相似文献
42.
Georgiana G. Surpateanu Catalin N. Lungu Sophie Fourmentin David Landy Narcis Avarvari 《Supramolecular chemistry》2013,25(5):372-378
We report the synthesis of 4,5-di(ethylthio)-4′-[6-deoxy-β-cyclodextrin-6-yl-aminocarbonyl]-tetrathiafulvalene (β-CD-DET-TTF) and its inclusion abilities towards cyclobis(paraquat-p-phenylene) (CBPQT4+ ) and 1-naphthol. The structure of the synthesised compound has been established by mass spectrometry and 1H NMR spectra combined with a theoretical MM3 and AM1 study. The sensor affords a charge transfer (CT) complex with the CBPQT4+ and is able to include 1-naphthol in the cyclodextrin cavity. The complexes were characterised experimentally by UV–vis spectroscopy and simulated by a MM3 docking procedure. The sensing ability of the β-CD-DET-TTF/CBPQT4+ complex towards 1-naphthol has been investigated by a competitive spectral method. The synthesis and characterisation of a new water soluble β-CD-DET-TTF derivative able to formed a CT complex with the CBPQT4+ acceptor is reported. The water soluble CT complex β-CD-DET-TTF/CBPQT4+ could be used as an efficient sensor towards aromatic guests prone to give inclusion complexes with the CBPQT4+ ring. 相似文献
43.
Thomas Biet Dr. Thomas Cauchy Dr. Narcis Avarvari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):16097-16103
Two series of 4‐ and 5‐tetrathiafulvalenyl‐1,2,3‐triazoles, as multifunctional ligands and precursors for molecular materials, have been synthesized by copper‐ or ruthenium‐based “click” chemistry. The solid‐state structures of three ligands and two CuII complexes were determined. Large differences in the electron‐donating properties between the 1,4‐ and 1,5‐isomers were evidenced by cyclic voltammetry. Theoretical calculations support this observation and allow the assignment of the electronic transitions observed in UV/Vis spectra of the ligands. 相似文献
44.
45.
Amidopyridine and -2,2'-bipyridine derivatives of EDT-TTF and BTM-TTF (EDT=ethylenedithio, BTM=bis(thiomethyl), TTF=tetrathiafulvalene) have been synthesized and crystallographically characterized. In the solid state, the different supramolecular organization of all these donors results from the competition between the intermolecular interactions, that is, van der Waals, hydrogen-bonding, pi-pi stacking, and donor-acceptor interactions. The electron-donating properties of the new donors have been investigated by cyclic voltammetry measurements. A radical cation salt, formulated [EDT-TTF-CONH-m-Py](.) (+)[PF(6)](-), has been prepared by electrocrystallization and its crystal structure determined by X-ray analysis. Square planar dicationic complexes with the same donor and M(II)L(2) fragments (M=Pd, Pt, L(2)=bis(diphenylphosphino)propane (dppp) or bis(diphenylphosphino)ethane (dppe)) have been synthesized and one of them, containing the Pd(dppp) unit, has been structurally characterized. The conformation of the complex in the crystalline state is anti, with the coexistence of the dl racemic pair of enantiomers. 相似文献
46.
Racemic and enantiopure ethylenedithio-tetrathiafulvalene (EDT-TTF) derivatives featuring β-hydroxyamide or oxazoline (OX) groups bearing methyl or isopropyl substituents have been synthesized starting from the corresponding amino alcohols. Crystal structure analysis shows in the case of the racemic methyl-β-hydroxyamide donor the development of a unique hydrogen bond network, characterized by short CO?H-O and N-H?O-H intermolecular distances. The enantiopure (S)-EDT-TTF-methyl-OX crystallizes in the monoclinic non-centrosymmetric space group P21, whereas the isopropyl counterparts, (R)-and (S)-EDT-TTF-isopropyl-OX, crystallize in the orthorhombic non-centrosymmetric space group P212121. All of them adopt a s-trans conformation in which TTF and oxazoline units are coplanar. Electrocrystallization experiments with the racemic EDT-TTF-methyl-OX, in the presence of (nBu4)2Mo6Cl14 as supporting electrolyte, afford a radical cation salt, formulated as [(±)-EDT-TTF-methyl-OX]2Mo6Cl14, in which the donors associate in strong dimers, which further stack along the b direction to form quasi-homochiral helix-like ribbons. 相似文献
47.
Nickel dithiolene complexes symmetrically appended with hydrogen-bond donor/acceptor functionalities such as imide, amide, or cyano/amide groups have been synthesized by a straightforward method of wide applicability starting from one single precursor. Single-crystal X-ray structures reveal the occurrence of one type of ribbon common to all compounds that is based on a recurrent self-complementary intermolecular hydrogen-bonded ring motif linking the symmetrically substituted complexes. 相似文献
48.
Hameau A Guyon F Knorr M Däschlein C Strohmann C Avarvari N 《Dalton transactions (Cambridge, England : 2003)》2008,(36):4866-4876
Novel organosilylated tetrathiafulvalenes (TTFs) possessing Si-H or Si-Si bonds have been synthesised. The crystal structures of several derivatives have been determined by X-ray diffraction, including that of dimeric (Si(2)Me(4))(TTF)(2) () incorporating a diatomic SiMe(2)-SiMe(2) linker. Cyclic voltammetry measurements in all cases show two oxidation waves. DFT calculations were performed to rationalize the absence of an electronic communication between the two TTF moieties of through the disilanyl spacer. The reactivity of the Si-H bond has been exploited to prepare the dinuclear complex [{Ru(CO)(4)}(2){mu-(Me(2)Si)(4)TTF}] (), starting from Ru(3)(CO)(12) and TTF(SiMe(2)H)(4) (). Treatment of with 2 equiv. of PPh(3) or dppm results in selective substitution of a CO ligand trans to a SiMe(2) group to afford mer-[{Ru(PPh(3))(CO)(3)}(2){mu-(Me(2)Si)(4)TTF}] () and mer-[{Ru(CO)(3)}(2)(eta(1)-dppm){mu-(Me(2)Si)(4)TTF}] (). Attempts to transform the Si-H bonds of some TTF(SiMe(2)H)(n) (n = 1, 2) into Si-O functions using stoichiometric amounts of water in the presence of tris(dibenzylideneacetone)dipalladium(0) were unsuccessful. Quantitative cleavage of the C(TTF)-Si bond was observed instead of formation of TTF-based-siloxanes. Essays of catalytic bis-silylation of phenylacetylene with and TTF(SiMe(2)-SiMe(3)) () in the presence of Pd(OAc)(2)/1,1,3,3-tetramethylbutylisocyanide failed. Again, cleavage of the C(TTF)-Si bond was noticed. 相似文献
49.
Elena Bartolom Ana Arauzo Sergio Herce Anna Palau Narcis Mestres Sara Fuertes Pablo Sevilla Nicholas S. Settineri Laura Navarro-Spreafico Jonay Gonzlez E. Carolina Saudo 《Molecules (Basel, Switzerland)》2021,26(18)
The synthesis of a terbium-based 2D metal–organic framework (MOF), of formula [Tb(MeCOO)(PhCOO)2] (1), a crystalline material formed by neutral nanosheets held together by Van der Waals interactions, is presented. The material can be easily exfoliated by sonication and deposited onto different substrates. Uniform distributions of Tb-2D MOF flakes onto silicon were obtained by spin-coating. We report the luminescent and magnetic properties of the deposited flakes compared with those of the bulk. Complex 1 is luminescent in the visible and has a sizeable quantum yield of QY = 61% upon excitation at 280 nm. Photoluminescence measurements performed using a micro-Raman set up allowed us to characterize the luminescent spectra of individual flakes on silicon. Magnetization measurements of flakes-on-silicon with the applied magnetic field in-plane and out-of-plane display anisotropy. Ac susceptibility measurements show that 1 in bulk exhibits field-induced slow relaxation of the magnetization through two relaxation paths and the slowest one, with a relaxation time of τlf ≈ 0.5 s, is assigned to a direct process mechanism. The reported exfoliation of lanthanide 2D-MOFs onto substrates is an attractive approach for the development of multifunctional materials and devices for different applications. 相似文献
50.
Dr. Adrian Gainar Dr. Thanh-Loan Lai Dr. Cristina Oliveras-González Dr. Flavia Pop Dr. Matthieu Raynal Dr. Benjamin Isare Dr. Laurent Bouteiller Dr. Mathieu Linares Dr. David Canevet Dr. Narcis Avarvari Prof. Marc Sallé 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2410-2420
Two-component organogels and xerogels based on a C3-symmetric pyrene-containing gelator have been deeply characterized through a wide range of techniques. Based on the formation of charge transfer complexes, the gelation phenomenon proved to be highly dependent on the nature of the electron poor dopant. This parameter significantly influenced the corresponding gelation domains, the critical gelation concentrations of acceptor dopants, the gel-to-sol transition temperatures, the microstructures formed in the xerogel state and their spectroscopic properties. In particular, titrations and variable-temperature UV–visible absorption spectroscopy demonstrated the key role of donor–acceptor interactions with a remarkable correlation between the phase transition temperatures and the disappearance of the characteristic charge transfer bands. The assignment of these electronic transitions was confirmed through time-dependent density functional theory (TD-DFT) calculations. Eventually, it was shown that the luminescent properties of these materials can be tuned with the temperature, either in intensity or emission wavelength. 相似文献