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1.
The cholesterol-bonded fullerene and porphyrin derivatives were synthesised and characterised. Donor–acceptor thin films were self-assembled through the interaction between cyclodextrin and the cholesterol groups on porphyrin and fullerene derivatives. These uniform films were characterised by ultraviolet–visible and fluorescence spectroscopies. Scanning electron microscopy indicated that the self-assembled film had a chain-like fibre structure with the chains having a diameter of about 50 nm. The intermolecular interaction between chromophores and the formation of complex based on cholesterol and cyclodextrin were proven by the quenching of fluorescence due to the charge transfer from porphyrin moieties to the fullerene units. 相似文献
2.
The reactions of [60]fullerene with amino acids and quaternary ammonium salts in toluene afforded two fulleropyrrolidine derivatives. One fulleropyrrolidine derivative contained a RCH moiety originating from quaternary ammonium salts through C–N bond cleavages and other fulleropyrrolidine derivatives contained a PhCH moiety originating from toluene through C–H bond cleavage. By using chlorobenzene instead of toluene as solvent, only one fulleropyrrolidine derivative containing a RCH moiety was obtained in the reactions. 相似文献
3.
D'Souza F Chitta R Gadde S Rogers LM Karr PA Zandler ME Sandanayaka AS Araki Y Ito O 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(3):916-922
Biomimetic bacterial photosynthetic reaction center complexes have been constructed using well-defined self-assembled supramolecular approaches. The "special pair" donor, a cofacial porphyrin dimer, was formed via potassium ion induced dimerization of meso-(benzo-[15]crown-5)porphyrinatozinc. The dimer was subsequently self-assembled with functionalized fullerenes via axial coordination and crown ether-alkyl ammonium cation complexation to form the donor-acceptor pairs, mimicking the noncovalently bound entities of the photosynthetic reaction center. The adopted self-assembly methodology yielded supramolecular complexes of higher stability, with defined geometry and orientation. Efficient forward electron transfer from the singlet excited zinc porphyrin dimer to the fullerene entity and relatively slow reverse electron transfer, important steps in the photosynthetic light energy conversion have been achieved in these novel biomimetic model systems. 相似文献
4.
Metal‐Atom Impact on the Self‐Assembly of Cup‐and‐Ball Metalloporphyrin–Fullerene Conjugates 下载免费PDF全文
Dr. Luis Moreira Joaquín Calbo Dr. Beatriz M. Illescas Dr. Juan Aragó Dr. Iwona Nierengarten Dr. Béatrice Delavaux‐Nicot Prof. Dr. Enrique Ortí Prof. Dr. Nazario Martín Prof. Dr. Jean‐François Nierengarten 《Angewandte Chemie (International ed. in English)》2015,54(4):1255-1260
A fullerene ammonium derivative has been combined with different metalloporphyrin–crown ether receptors to generate very stable supramolecules. The combination of fullerene–porphyrin and ammonium–crown ether interactions leads to a strong chelate effect as evidenced by a high effective molarity (3.16 M ). The different parameters influencing the stability of the supramolecular ensembles, in particular the nature of the metal in the porphyrin moiety, have been rationalized with the help of theoretical calculations thus providing new insights into fullerene–porphyrin interactions. 相似文献
5.
D'Souza F Chitta R Gadde S McCarty AL Karr PA Zandler ME Sandanayaka AS Araki Y Ito O 《The journal of physical chemistry. B》2006,110(12):5905-5913
Photoinduced electron-transfer processes in cis and trans functionalized bis-18-crown-6 porphyrin self-assembled with fullerene functionalized with pyridine or alkylammonium cation entities are reported. The structural integrity of the newly formed supramolecular conjugates was accomplished by optical absorption and emission, electron spray ionization mass, electrochemistry, and semiempirical PM3 calculations. A 1:2 stoichiometry of the supramolecular porphyrin:fullerene conjugates was deduced from these studies. The conjugates revealed stable "two-point"' binding involving metal-ligand coordination and alkylammonium cation-crown ether binding or only the latter type of binding depending upon the functionality of the fullerene and metal ion in the porphyrin cavity. The effect of the variation on free energy changes of charge separation and the charge recombination was achieved by varying the metal ion in the porphyrin cavity. The charge-separation rates (k(CS)) determined from the picosecond time-resolved emission studies were generally higher for the cis bis-crown functionalized porphyrins than those of the corresponding trans ones. A comparison of the k(CS) values reported earlier for 1:1 porphyrin-fullerene conjugates with a similar self-assembly mechanism suggested that employing a higher number of acceptor entities improves the electron-transfer rates. The calculated charge-recombination rates (k(CR)) were 2-3 orders of magnitude smaller than the k(CS) values, suggesting the occurrence of the charge recombination process in the Marcus inverted region. The lifetimes of the radical ion pair (tau(RIP)) ranged between 46 and 233 ns indicating charge stabilization in the studied conjugates. 相似文献
6.
Photoinduced electron transfer in a hexaphenylbenzene-based self-assembled porphyrin-fullerene triad
Terazono Y Kodis G Liddell PA Garg V Gervaldo M Moore TA Moore AL Gust D 《Photochemistry and photobiology》2007,83(2):464-469
A hexaphenylbenzene-based zinc porphyrin dyad forms a 1:1 complex with a fullerene bearing two pyridyl groups via coordination of the pyridyl nitrogens with the zinc atoms. The fullerene is symmetrically located between the two zinc porphyrins. The binding constant for the complex is 7.3 x 10(4) M(-1) in 1,2-difluorobenzene. Photoinduced electron transfer from a porphyrin first excited singlet state to the fullerene occurs with a time constant of 3 ps, and the resulting charge-separated state has a lifetime of 230 ps. This self-assembled construct should form a basis for the construction of more elaborate model photosynthetic antenna-reaction center systems. 相似文献
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8.
Novel amphiphilic cationic cellulose (HMQC) derivatives carrying long chain alkyl groups as hydrophobic moieties and quaternary ammonium groups as hydrophilic moieties were synthesized. Structure and properties of the amphiphilic cellulose derivatives were characterized by elemental analysis, FT-IR, (1)H NMR, ζ-potential measurement, dynamic light scattering (DLS), fluorescence spectroscopy and transmission electron microscopy (TEM). The results revealed that HMQCs can be self-assembled into cationic micelles in distilled water with the average hydrodynamic radius of 320-430 nm. The cytotoxicity study showed that the HMQC exhibited low cytotoxicity. Prednisone acetate, a water insoluble anti-inflammation drug, was chosen as a model drug to investigate the utilization of self-assembled HMQC micelles as a delivery carrier for poorly water-soluble drugs. The study indicated that the prednisone acetate could be incorporated effectively in the self-assembled HMQC micelles and be controlled released. 相似文献
9.
Jean-Pascal Bourgeois Franois Diederich Luis Echegoyen Jean-Franois Nierengarten 《Helvetica chimica acta》1998,81(10):1835-1844
The synthesis of the cyclophane-type molecular dyads 1 and 1 . Zn was accomplished by Bingel macrocyclization of porphyrin-tethered bis-malonates 5 or 5 . Zn , respectively, with C60 (Scheme). In these macrocycles, the doubly bridged porphyrin adopts a close, tangential orientation relative to the surface of the C-sphere. The porphyrin derivatives 6 and 6 . Zn with two appended, singly-linked C60 moieties were also formed as side products in the Bingel macrocyclizations. The trans-1 addition pattern of the fullerene moiety in 1 and 1 . Zn was unambiguously established by 1H- and 13C-NMR spectroscopy. Due to the close spatial relationship between the fullerene and porphyrin components in 1 and 6 and the corresponding ZnII complexes, the porphyrin fluorescence is efficiently quenched as compared to the luminescence emitted by 5 and 5 . Zn , respectively (Fig. 2). Cyclic-voltammetry studies show that the mutual electronic effects exerted by the fullerene on the porphyrin and vice versa in 1 and 1 . Zn are relatively small despite the close proximity between the porphyrin donor and the fullerene acceptor (Fig. 3). 相似文献
10.
Hasobe T Imahori H Kamat PV Fukuzumi S 《Journal of the American Chemical Society》2003,125(49):14962-14963
Novel organic solar cells prepared using quaternary self-organization of porphyrin (donor) and fullerene (acceptor) dye units by clusterization with gold nanoparticles on SnO2 electrodes exhibit the remarkable enhancement of the photoelectrochemical properties relative to the reference systems. 相似文献
11.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(10):2738-2742
A star‐shaped electron acceptor based on porphyrin as a core and perylene bisimide as end groups was constructed for application in non‐fullerene organic solar cells. The new conjugated molecule exhibits aligned energy levels, good electron mobility, and complementary absorption with a donor polymer. These advantages facilitate a high power conversion efficiency of 7.4 % in non‐fullerene solar cells, which represents the highest photovoltaic performance based on porphyrin derivatives as the acceptor. 相似文献
12.
Two new beta-substituted arylethynyl meso-tetraphenylporphyrins, 2-[(4'-formyl)phenyl]ethynyl-5,10,15,20-tetraphenylporphyrin (system A) and 2-[(4'-methyl)phenyl]ethynyl-5,10,15,20-tetraphenylporphyrin (system B) and their zinc derivatives were synthesized by palladium catalysis, using a synthetic approach that affords high yields of the target systems. Comparative ultraviolet-visible (UV-vis), NMR, and cyclic voltammetry studies of such macrocycles reveal the presence of an extensive conjugation between the tetrapyrrolic ring and the linker, through pi-pi orbital interaction. This interaction was observed in the form of a "push-pull" effect that moves the electronic charge between the porphyrin and the aldehyde group of system A. System B, bearing a methyl group instead of the formyl group, was synthesized in order to evaluate the effect of the substitution on the charge delocalization, which is necessary to corroborate the push-pull mechanism hypothesis. The new porphyrin, system A, was also used as a starting material for the synthesis of new porphyrin-fullerene dyads in which the [60]fullerene is directly linked to the tetrapyrrolic rings by ethynylenephenylene subunits. Fluorescence and transient absorption measurements of the new dyads reveal that ultrafast energy and electron transfer occur, respectively, in nonpolar and polar solvents, with high values of the rate constant. The UV-vis, NMR, and cyclic voltammetry results show that it is possible for both energy and electron transfer between porphyrin and fullerene to take place through the pi-bond interaction. Such results evidence that the coupling between the donor and acceptor moieties is strong enough for possible photovoltaic applications. 相似文献
13.
Hernández-Eguía LP Escudero-Adán EC Pinzón JR Echegoyen L Ballester P 《The Journal of organic chemistry》2011,76(9):3258-3265
We report the synthesis of two cyclic β-pyrrole unsubstituted meso-tetraphenyl bisporphyrins in which the porphyrin units are connected by two 2,3-hexadiynyl-1,6-dioxo or two hexyl-1,6-dioxo spacers, respectively. Both cyclic porphyrin dimers exist in solution as mixtures of two conformational isomers. In the solid state, the receptor with diynyl spacers forms a 1:1 complex with the icosahedral (I(h)) isomer of the trimetallic nitride endohedral fullerene Sc(3)N@C(80). In this complex the receptor adopts a scoop-shaped conformation having a dihedral angle of 87.25° between the two porphyrin planes. The hexyl spaced analogue, however, adopts a similar conformation upon encapsulation of one molecule of Sc(3)N@C(80) in a self-assembled dimeric capsule. The capsular complexes pack in columns and render the fullerene units completely isolated. In toluene solution, (1)H NMR experiments indicate that the endohedral fullerene Sc(3)N@C(80) is exclusively bound by the expanded isomer of both dimers. UV-vis and fluorescence titration experiments confirmed the existence of strong π-π interactions between the fullerene Sc(3)N@C(80) and the flexible bisporphyrin dimer with hexyl spacers. At micromolar concentration, the flexible receptor forms only a 1:1 complex with the endohedral fullerene with stability constant value of K(a) = 2.6 ± 0.3 × 10(5) M(-1). 相似文献
14.
Andreas Kiebele Davide Bonifazi Fuyong Cheng Meike St?hr Fran?ois Diederich Thomas Jung Hannes Spillmann 《Chemphyschem》2006,7(7):1462-1470
Herein, a detailed investigation of the adsorption and dynamics of C60 and C70 fullerenes hosted in a self-assembled, two-dimensional, nanoporous porphyrin network on a solid Ag surface is presented. Time-resolved scanning tunneling microscopy (STM) studies of these supramolecular systems at the molecular scale reveal distinct host-guest interactions giving rise to a pronounced dissimilar mobility of the two fullerenes within the porphyrin network. Furthermore, long-range coverage-dependent interactions between the all-carbon guests, which clearly affect their mobility and are likely mediated by a complex mechanism involving the Ag substrate and the flexible porphyrin host network, are observed. At increased fullerene coverage, this unprecedented interplay results in the formation of large fullerene chains and islands. By applying a lattice gas model with nearest-neighbor interactions and by evaluating the fullerene-pair distribution functions, the respective coverage-dependent guest-guest interaction energies are estimated. 相似文献
15.
Photovoltaic cells using composite nanoclusters of porphyrins and fullerenes with gold nanoparticles
Hasobe T Imahori H Kamat PV Ahn TK Kim SK Kim D Fujimoto A Hirakawa T Fukuzumi S 《Journal of the American Chemical Society》2005,127(4):1216-1228
Novel organic solar cells have been prepared using quaternary self-organization of porphyrin (donor) and fullerene (acceptor) units by clusterization with gold nanoparticles on nanostructured SnO2 electrodes. First, porphyrin-alkanethiolate monolayer-protected gold nanoparticles (H2PCnMPC: n is the number of methylene groups in the spacer) are prepared (secondary organization) starting from the primary component (porphyrin-alkanethiol). These porphyrin-modified gold nanoparticles form complexes with fullerene molecules (tertiary organization), and they are clusterized in acetonitrile/toluene mixed solvent (quaternary organization). The highly colored composite clusters can then be assembled as three-dimensional arrays onto nanostructured SnO2 films to afford the OTE/SnO2/(H2PCnMPC+C60)m electrode using an electrophoretic deposition method. The film of the composite clusters with gold nanoparticle exhibits an incident photon-to-photocurrent efficiency (IPCE) as high as 54% and broad photocurrent action spectra (up to 1000 nm). The power conversion efficiency of the OTE/SnO2/(H2PC15MPC+C60)m composite electrode reaches as high as 1.5%, which is 45 times higher than that of the reference system consisting of the both single components of porphyrin and fullerene. 相似文献
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17.
Binding constants and thermodynamic parameters for 1:1 complexation of a porphyrin macroring, self-assembled from three trisporphyrinatozinc through imidazole-Zn coordination on the terminal porphyrins, with several multidentate pyridyl and fullerenyl ligands were examined. In benzonitrile, the ligand having one fullerenyl and two coordinative pyridyl moieties surprisingly afforded the highest affinity. The thermodynamic data of the complexation indicated that an unusual and fairly large positive entropic change, which may be attributed to extensive desolvation of the solutes especially from the large cavity of porphyrin macroring and fullerene surface, significantly contributed to the enhancement of the binding constant. 相似文献
18.
D'Souza F Smith PM Rogers L Zandler ME Shafiqul Islam DM Araki Y Ito O 《Inorganic chemistry》2006,45(13):5057-5065
Donor-acceptor dyads were constructed using zinc N-confused porphyrin (ZnNCP), a structural isomer of zinc tetraphenylporphyrin, as a donor, and fullerene as an electron acceptor. Two derivatives, pyridine-coordinated zinc N-confused porphyrin (Py:ZnNCP) and the zinc N-confused porphyrin dimer (ZnNCP-dimer) were utilized to form the dyads with an imidazole-appended fulleropyrrolidine (C60Im). These porphyrin isomers formed well-defined 1:1 supramolecular dyads (C60Im:ZnNCP) via axial coordination. The dyads were characterized by optical absorption and emission, ESI-mass, 1H NMR, and electrochemical methods. The binding constant, K, was found to be 2.8 x 10(4) M(-1) for C60Im:ZnNCP. The geometric and electronic structure of C60Im:ZnNCP were probed by using DFT B3LYP/3-21G methods. The HOMO was found to be on the ZnNCP entity, while the LUMO was primarily on the fullerene entity. The electrochemical properties of C60Im:ZnNCP was probed using cyclic voltammetry in o-dichlorobenzene, 0.1 n-Bu4NClO4. The Py:ZnNCP was found to be easier to oxidize by over 340 mV compared to Py:ZnTPP. Upon dyad formation via axial coordination, the first oxidation revealed an anodic shift of nearly 90 mV. Evidence of photoinduced charge separation from the singlet excited ZnNCP to the appended fullerene was established from time-resolved emission and nanosecond transient absorption studies. 相似文献
19.
Silva EM Serra VV Ribeiro AO Tomé JP Domingues P Faustino MA Neves MG Tomé AC Cavaleiro JA Ferrer-Correia AJ Iamamoto Y Domingues MR 《Rapid communications in mass spectrometry : RCM》2006,20(23):3605-3611
Novel cationic porphyrin derivatives having a galactose or a bis(isopropylidene)galactose unit linked directly to a pyridine or to an aminophenyl group were characterized by electrospray tandem mass spectrometry (ESI-MS/MS). The electrospray mass spectra (ESI-MS) show the M(+) ions, since these porphyrins are already monocharged in solution. The fragmentation of these ions under ESI-MS/MS conditions was studied and it was found that elimination of the sugar residue as a radical (-163 or -243 Da) is a common fragmentation pathway. Loss of the sugar unit as a neutral fragment (-162 or -242 Da) and cross-ring fragmentations typical of glyco-derivatives are also observed for the pyridinium glycoporphyrins, but they are absent in the case of ammonium glycoporphyrins. The cationic beta-pyridiniumvinyl porphyrins show an atypical fragmentation due to the cleavage of the C(5)-C(6) bond of the sugar unit. Overall, the different patterns of fragmentation observed in the ESI-MS/MS spectra of the sugar pyridinium porphyrins and of the sugar ammonium phenyl porphyrins can give important information about the type of spacer between the porphyrin and the sugar unit. 相似文献