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51.
Inside Back Cover: Synthesis and Isolation of the Titanium–Scandium Endohedral Fullerenes—Sc2TiC@Ih‐C80, Sc2TiC@D5h‐C80 and Sc2TiC2@Ih‐C80: Metal Size Tuning of the TiIV/TiIII Redox Potentials (Chem. Eur. J. 37/2016)
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52.
Synthesis of Cationic Dumbbell-shaped Fullerene Nanostructures as Potential Photodynamic Sensitizers
A design of novel hydrophilic tetracationic dumbbell-shaped [60]fullerene nanostructures was made by balancing the hydrophilicity and hydrophobicity characteristics of the fullerene adduct for their potential application as photodynamic sensitizers in the PDT treatment. A sequential protection-deprotection reaction pathway was applied for the functional differentiation between primary and secondary amine moieties of pentaethylene hexamine. Synthesis of the target molecule involves two key steps of unsymmetrical esterification and amidation of malonic acid and subsequent fullerenation. The synthetic strategy was accomplished using mild reaction conditions in the intermediate molecule preparation and led a moderate overall product yield. 相似文献
53.
Rong‐Ho Lee Jian‐Lun Huang Chun‐Han Chi 《Journal of Polymer Science.Polymer Physics》2013,51(2):137-148
In this study, the maleimide‐thiophene copolymer‐functionalized graphite oxide sheets (PTM21‐GOS) and carbon nanotubes (PTM21‐CNT) were developed for polymer solar cell (PSC) applications. The grafting of PTM21‐OH onto the CNT and GO sheets was confirmed using FTIR spectroscopy. PTM21‐CNT and PTM21‐GOS exhibited excellent dispersal behavior in organic solvents. Better thermal stability was observed for PTM21‐CNT and PTM21‐GOS as compared with that for PTM21‐OH. In addition, the optical band gaps of PTM21‐GOS and PTM21‐CNT were lower than that of PTM21‐OH. We incorporated PTM21‐GOS and PTM21‐CNT individually into poly(3‐hexylthiophene) (P3HT)/[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) blends for use as photoconversion layers of PSCs. Good distributional homogeneity was observed for PTM21‐GOS or PTM21‐CNT in the P3HT/PCBM blend film. The UV–vis absorption peaks of the blend films red‐shifted slightly upon increasing the content of PTM21‐GOS or PTM21‐CNT. The band gap energies and LUMO/HOMO energy levels of the P3HT/PTM21‐GOS and P3HT/PTM21‐CNT blend films were slightly lower than those of the P3HT film. The conjugated polymer‐functionalized PTM21‐GOS and PTM21‐CNT behaved as efficient electron acceptors and as charge‐transport assisters when incorporated into the photoactive layers of the PSCs. PV performance of the PSCs was enhanced after incorporating PTM21‐GOS or PTM21‐CNT in the P3HT/PCBM blend. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 相似文献
54.
《Journal of computational chemistry》2017,38(19):1661-1667
Experimentally characterized endohedral metallofullerenes are of current interest in expanding the range of viable fullerenic structures and their applications. Smaller metallofullerenes, such as M@C28, show that several d‐ and f‐block elements can be efficiently confined in relatively small carbon cages. This article explores the potential capabilities of the smallest fullerene cage, that is, C20, to encapsulate p‐block elements from group 14, that is, E = Si, Ge, Sn, and Pb. Our interest relates to the bonding features and optical properties related to E@C20. The results indicate both s‐ and p‐type concentric bonds, in contrast to the well explored endohedral structures encapsulating f‐block elements. Our results suggest the E@C20 series to be a new family of viable endohedral fullerenes. In addition spectroscopic properties related to electron affinity, optical, and vibrational were modeled to gain further information useful for characterization. Characteristic optical patterns were studied predicting a distinctive first peak located between 400 and 250 nm, which is red‐shifted going to the heavier encapsulated Group 14 atoms. Electron affinity properties expose different patterns useful to differentiate the hollow C20 fullerene to the proposed p‐block endohedral counterparts. © 2017 Wiley Periodicals, Inc. 相似文献
55.
Dr. Yong Guo Dr. Wengang Li Dr. Jingjing Yan Dr. Basem Moosa Dr. Ma'an Amad Prof. Charles J. Werth Prof. Niveen M. Khashab 《化学:亚洲杂志》2012,7(12):2842-2847
Metal‐free fullerene (C60) was found to be an effective catalyst for the reduction of azo groups in basic aqueous solution under UV irradiation in the presence of NaBH4. Use of NaBH4 by itself is not sufficient to reduce the azo dyes without the assistance of a metal catalyst such as Pd and Ag. Experimental and theoretical results suggest that C60 catalyzes this reaction by using its vacant orbital to accept the electron in the bonding orbital of azo dyes, which leads to the activation of the N?N bond. UV irradiation increases the ability of C60 to interact with electron‐donor moieties in azo dyes. 相似文献
56.
Dr. Israel Fernández Prof. Dr. Miquel Solà Prof. Dr. F. Matthias Bickelhaupt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7416-7422
The origin of the experimentally known preference for [6,6] over [5,6] bonds in cycloaddition reactions involving C60 has been computationally explored. To this end, the Diels–Alder reaction between cyclopentadiene and C60 has been analysed by means of the recently introduced activation strain model of reactivity in combination with the energy decomposition analysis method. Other issues, such as the aromaticity of the corresponding transition states, have also been considered. These results indicate that the major factor controlling the observed regioselectivity is the more stabilising interaction between the deformed reactants in the [6,6] reaction pathway along the entire reaction coordinate. 相似文献
57.
Dr. Timothy A. Barendt Dr. Melissa L. Ball Dr. Qizhi Xu Dr. Boyuan Zhang Dr. Brandon Fowler Ayden Schattman Virginia Cary Ritter Prof. Michael L. Steigerwald Prof. Colin Nuckolls 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(17):3744-3748
This work presents a synergy between organic electronics and supramolecular chemistry, in which a host–guest complex is designed to function as an efficacious electronic material. Specifically, the noncovalent recognition of a fullerene, phenyl-C61-butyric acid methyl ester ( PC61BM ), by an alternating perylene diimide ( P )-bithiophene ( B ) conjugated macrocycle ( PBPB ) results in a greater than five-fold enhancement in electron mobility, relative to the macrocycle alone. Characterization and quantification of the binding of fullerenes by host PBPB is provided alongside evidence for intermolecular electronic communication within the host–guest complexes. 相似文献
58.
Dr. Antony J. Stasyuk Dr. Olga A. Stasyuk Prof. Dr. Miquel Solà Prof. Dr. Alexander A. Voityuk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(10):2577-2585
Porphyrin–fullerene dyads are promising candidates for organic photovoltaic devices. The electron-transfer (ET) properties of the molecular devices depend significantly on the mutual position of the donor and acceptor. Recently, a new type of molecular isomerism (akamptisomerism) has been discovered. In the present study, we explore how photoinduced ET can be modulated by passing from one akamptisomer to another. To this aim, four akamptisomers of the quinoxalinoporphyrin–[60]fullerene complex are selected for computational study. The most striking finding is that, depending on the isomer, the porphyrin unit in the dyad can act as either electron donor or electron acceptor. Thus, the stereoisomeric diversity allows one to change the direction of ET between the porphyrin and fullerene moieties. To understand the effect of akamptisomerism on the photoinduced ET processes, a detailed analysis of initial and final states involved in the ET is performed. The computed rate for charge separation is estimated to be in the region of 1–10 ns−1. The formation of a long-living quinoxalinoporphyrin anion radical species is predicted. 相似文献
59.
Prof. Shinji Toyota Dr. Eiji Tsurumaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6878-6890
Saturn-like systems consisting of nanoscale rings and spheres are fascinating motifs in supramolecular chemistry. Several ring molecules are known to include spherical molecules at the center of the cavity via noncovalent attractive interactions. In this Minireview, we generalize the molecular design, the structural features, and the supramolecular chemistry of such “nano-Saturns”, which consist of monocyclic rings and fullerene spheres (mainly C60), on the basis of previous experimental and theoretical studies. Ring molecules are classified into three types (loop, belt, and disk) according to their shapes and possible interactions. Whereas typical belt-shaped rings tend to form tight complexes due to the wide contact area via π–π interactions, flat disk-shaped rings generally form weak complexes due to the narrow contact area mainly via CH–π interactions. In spite of the small association energies, disk-shaped rings are attractive because such rings can mimic the planet Saturn precisely as exemplified by an anthracene cyclic hexamer–C60 complex. 相似文献
60.
Benjamin H. Strudwick Mark A. J. Koenis Hans J. Sanders Valentin P. Nicu Sander Woutersen Prof. Wybren Jan Buma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(54):12560-12566
Vibrational circular dichroism (VCD) studies are reported on a chiral compound in which a fullerene C60 moiety is used as an electron acceptor and local VCD amplifier for an alanine-based peptide chain. Four redox states are investigated in this study, of which three are reduced species that possess low-lying electronic states as confirmed by UV/Vis spectroelectrochemistry. VCD measurements in combination with (TD)DFT calculations are used to investigate (i) how the low-lying electronic states of the reduced species modulate the amplification of VCD signals, (ii) how this amplification depends on the distance between oscillator and amplifier, and (iii) how the spatial extent of the amplifier influences amplification. These results pave the way for further development of tailored molecular VCD amplifiers. 相似文献