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1.
《Angewandte Chemie (International ed. in English)》2017,56(1):158-162
Herein we report the organoplatinum‐mediated bottom‐up synthesis, characterization, and properties of a novel large π‐extended carbon nanoring based on a nanographene hexa‐peri ‐hexabenzocoronene (HBC) building unit. This tubular structure can be considered as an example of the longitudinal extension of the cycloparaphenylene scaffold to form a large π‐extended carbon nanotube (CNT) segment. The cyclic tetramer of a tetramesityl HBC ([4]CHBC) was synthesized by the reaction of a 2,11‐diborylated hexa‐peri ‐hexabenzocoronene with a platinum complex, followed by reductive elimination. The structure of this tubular molecule was further confirmed by physical characterization. Theoretical calculations indicate that the strain energy of this nanoring is as high as 49.18 kcal mol−1. The selective supramolecular host–guest interaction between [4]CHBC and C70 was also investigated. 相似文献
2.
Alternating Donor–Acceptor Arrays from Hexa‐peri‐hexabenzocoronene and Benzothiadiazole: Synthesis,Optical Properties,and Self‐Assembly 下载免费PDF全文
Felix Hinkel Dr. Don Cho Dr. Wojciech Pisula Prof. Dr. Martin Baumgarten Prof. Klaus Müllen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):86-90
Donor–acceptor (D–A) structures were obtained by alternating arrays of hexa‐peri‐hexabenzocoronene (HBC) and benzo[c][1,2,5]thiadiazole (BTZ). Optoelectronic investigations revealed a charge transfer due to strong push–pull interactions. 2 D wide‐angle X‐ray scattering (WAXS) data indicated an arrangement in liquid‐crystalline columnar assemblies, in which the π‐stacking distances and molecular orientation depend on the number of HBC units in the molecules. 相似文献
3.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(30):9474-9479
Herein we report the synthesis and photophysical and supramolecular properties of a novel three‐dimensional capsule‐like hexa‐peri‐hexabenzocoronene (HBC)‐containing carbon nanocage, tripodal‐[2]HBC, which is the first synthetic model of capped zigzag [12,0] carbon nanotubes (CNTs). Tripodal‐[2]HBC was synthesized by the palladium‐catalyzed coupling of triboryl hexabenzocoronene and L‐shaped cyclohexane units, followed by nickel‐mediated C−Br/C−Br coupling and subsequent aromatization of the cyclohexane moieties. The physical properties of tripodal‐[2]HBC and its supramolecular host–guest interaction with C70 were further studied by UV/Vis and fluorescence spectroscopy. Theoretical calculations revealed that the strain energy of tripodal‐[2]HBC was as high as 55.2 kcal mol−1. 相似文献
4.
A Three‐Dimensional Capsule‐like Carbon Nanocage as a Segment Model of Capped Zigzag [12,0] Carbon Nanotubes: Synthesis,Characterization, and Complexation with C70 下载免费PDF全文
Dapeng Lu Qiang Huang Hongxing Jia Ya Wang Prof. Shangfeng Yang Prof. Pingwu Du 《Angewandte Chemie (International ed. in English)》2018,57(30):9330-9335
Herein we report the synthesis and photophysical and supramolecular properties of a novel three‐dimensional capsule‐like hexa‐peri‐hexabenzocoronene (HBC)‐containing carbon nanocage, tripodal‐[2]HBC, which is the first synthetic model of capped zigzag [12,0] carbon nanotubes (CNTs). Tripodal‐[2]HBC was synthesized by the palladium‐catalyzed coupling of triboryl hexabenzocoronene and L‐shaped cyclohexane units, followed by nickel‐mediated C?Br/C?Br coupling and subsequent aromatization of the cyclohexane moieties. The physical properties of tripodal‐[2]HBC and its supramolecular host–guest interaction with C70 were further studied by UV/Vis and fluorescence spectroscopy. Theoretical calculations revealed that the strain energy of tripodal‐[2]HBC was as high as 55.2 kcal mol?1. 相似文献
5.
Hengxing Wei Dr. Ying‐Ying Li Dr. Jinping Chen Dr. Yi Zeng Prof. Dr. Guoqiang Yang Prof. Dr. Yi Li 《化学:亚洲杂志》2012,7(11):2683-2689
An imidazolium‐modified hexa‐peri‐hexabenzocoronene derivative (HBC‐C11‐MIM[Cl?]) was designed and synthesized as a stabilizer to fabricate reduced graphene oxide (RGO). The resulting RGO/HBC‐C11‐MIM[Cl?] hybrid shows excellent dispersivity (5.0 mg mL?1) and stability in water. RGO/HBC‐C11‐MIM[Cl?] was comprehensively characterized by using atomic force microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, thermogravimetric analysis, and Raman spectroscopy, thus revealing that one HBC‐C11‐MIM[Cl?] group can stabilize about 178 carbon atoms on the graphene sheets. The obtained hybrid film exhibits a high conductivity of 286 S m?1. Furthermore, the HBC‐C11‐MIM[Cl?]‐modified RGO sheets can be readily dispersed in polar organic solvents upon exchange of the hydrophilic Cl? ions for hydrophobic bis(trifluoromethylsulfonyl) amide (NTf2?) ions. 相似文献
6.
Dr. Matthias Krieg Florian Reicherter Dr. Peter Haiss Dr. Markus Ströbele Dr. Klaus Eichele Michael‐John Treanor Prof. Dr. Renald Schaub Prof. Dr. Holger F. Bettinger 《Angewandte Chemie (International ed. in English)》2015,54(28):8284-8286
The synthesis of a hexa‐peri‐hexabenzocoronene (HBC) with a central borazine core is described. The solid‐state structure of this BN‐doped HBC (BN‐HBC) is isotypic with that of the parent HBC. Scanning tunneling microscopy shows that BN‐HBC lies flat on Au(111) in a two‐dimensional pattern. 相似文献
7.
Vicente G. Jimnez Arthur H. G. David Juan M. Cuerva Victor Blanco Araceli G. Campaa 《Angewandte Chemie (International ed. in English)》2020,59(35):15124-15128
A cyclophane is reported incorporating two units of a heptagon‐containing extended polycyclic aromatic hydrocarbon (PAH) analogue of the hexa‐peri‐hexabenzocoronene (HBC) moiety (hept‐HBC). This cyclophane represents a new class of macrocyclic structures that incorporate for the first time seven‐membered rings within extended PAH frameworks. The saddle curvature of the hept‐HBC macrocycle units induced by the presence of the nonhexagonal ring along with the flexible alkyl linkers generate a cavity with shape complementarity and appropriate size to enable π interactions with fullerenes. Therefore, the cyclophane forms host–guest complexes with C60 and C70 with estimated binding constants of Ka=420±2 m ?1 and Ka=(6.49±0.23)×103 m ?1, respectively. As a result, the macrocycle can selectively bind C70 in the presence of an excess of a mixture of C60 and C70. 相似文献
8.
Oxa[7]superhelicene: A π‐Extended Helical Chromophore Based on Hexa‐peri‐hexabenzocoronenes 下载免费PDF全文
David Reger Philipp Haines Dr. Frank W. Heinemann Prof. Dr. Dirk M. Guldi Prof. Dr. Norbert Jux 《Angewandte Chemie (International ed. in English)》2018,57(20):5938-5942
A novel π‐extended “superhelicene” based on hexa‐peri‐hexabenzocoronenes (HBCs) has been synthesized by an efficient four‐step synthetic procedure starting from diphenyl ether. Comprehensive structural analysis of the helicene was performed by NMR spectroscopy and mass spectrometry measurements together with X‐ray analysis. Physicochemical analysis of the superhelicene and suitable HBC references revealed it had outstanding fluorescent features with quantum yields of over 80 %. 相似文献
9.
Selective Synthesis of Single‐ and Multi‐Walled Supramolecular Nanotubes by Using Solvophobic/Solvophilic Controls: Stepwise Radial Growth via “Coil‐on‐Tube” Intermediates 下载免费PDF全文
Dr. Seelam Prasanthkumar Dr. Wei Zhang Prof. Dr. Wusong Jin Prof. Dr. Takanori Fukushima Prof. Dr. Takuzo Aida 《Angewandte Chemie (International ed. in English)》2015,54(38):11168-11172
Novel hexa‐peri‐hexabenzocoronene (HBC) derivatives, FHBC and FHBC*, which carry perfluoroalkyl segments on one side of the HBC core and long alkyl tails on the other, were synthesized. Their perfluoroalkyl segments are highly solvated in C6F6 (solvophilic effect) and do not assemble, whereas in CH2Cl2, they are excluded (solvophobic effect) and assemble together consequently. For example, the use of C6F6 and CH2Cl2 as assembling media for FHBC leads to the selective formation of single‐ and multi‐walled nanotubes, respectively. When a higher monomer concentration is applied in CH2Cl2, multi‐walled nanotubes with a larger number of walls result. FHBC in CH2Cl2 self‐assembles rather slowly, thereby allowing for the observation of coil‐on‐tube structures, which are possible intermediates for the stepwise radial growth of the nanotubular wall. Casting of the multi‐walled nanotubes onto a quartz plate yields a superhydrophobic thin film with a water contact angle of 161±2°. 相似文献
10.
Exfoliation of Graphite into Graphene in Polar Solvents Mediated by Amphiphilic Hexa‐peri‐hexabenzocoronene 下载免费PDF全文
Ryota Kabe Prof. Xinliang Feng Prof. Chihaya Adachi Prof. Klaus Müllen 《化学:亚洲杂志》2014,9(11):3125-3129
A water‐soluble surfactant consisting of hexa‐peri‐hexabenzocoronene (HBC) as hydrophobic aromatic core and hydrophilic carboxy substituents was synthesized. It exhibited a self‐assembled nanofiber structure in the solid state. Profiting from the π interactions between the large aromatic core of HBC and graphene, the surfactant mediated the exfoliation of graphite into graphene in polar solvents, which was further stabilized by the bulky hydrophilic carboxylic groups. A graphene dispersion with a concentration as high as 1.1 mg L?1 containing 2–6 multilayer nanosheets was obtained. The lateral size of the graphene sheets was in the range of 100–500 nm based on atomic force microscope (AFM) and transmission electron microscope (TEM) measurements. 相似文献
11.
Sulfur‐Annulated Hexa‐peri‐hexabenzocoronene Decorated with Phenylthio Groups at the Periphery 下载免费PDF全文
Dr. Yuan‐Zhi Tan Dr. Silvio Osella Yi Liu Bo Yang Prof. Dr. David Beljonne Prof. Dr. Xinliang Feng Prof. Dr. Klaus Müllen 《Angewandte Chemie (International ed. in English)》2015,54(10):2927-2931
The chemical nature of the edge periphery essentially determines the physical properties of graphene. As a molecular‐level model system, large polycyclic aromatic hydrocarbons, that is, so‐called nanographenes, can be chemically modified through either edge functionalization or doping with heteroatoms. Although the synthetic methods for edge substitution are well‐developed, incorporation with heteroatoms by the bay annulation of large PAHs remains an enormous challenge. In this study, we present a feasible peripheral sulfur annulation of hexa‐peri‐hexabenzocoronene (HBC) by thiolation of perchlorinated HBC. The tri‐sulfur‐annulated HBC and di‐sulfur‐annulated HBC decorated with phenylthio groups were obtained and characterized by X‐ray diffraction, revealing their distinct sulfur‐annulated peripheral structure. Associated with theoretical calculations, we propose that the regioselective sulfur annulation results from the minimization of strain in the aromatic backbone. We further demonstrate the structure‐correlated property modulation by sulfur annulation, manifested by a decrease in band gap and tunable redox activity. 相似文献
12.
Guangwu Li Taisuke Matsuno Yi Han Hoa Phan Shaofei Wu Qing Jiang Ya Zou Hiroyuki Isobe Jishan Wu 《Angewandte Chemie (International ed. in English)》2020,59(24):9727-9735
Synthesis of fully conjugated cyclophanes containing large‐size polycyclic aromatics is challenging. Now, three benzidine‐linked, hexa‐peri‐hexabenzocoronene (superbenzene)‐based ortho‐, para‐, and meta‐cyclophanes are synthesized through intermolecular Yamamoto coupling reaction of structurally pre‐organized precursors. Subsequent oxidative dehydrogenation gave the corresponding quinoidal benzidine‐linked cyclophanes. Their geometries were confirmed by X‐ray crystallographic analysis and their electronic properties were investigated by electronic absorption, cyclic voltammetry, and DFT calculations. The quinoidal benzidine‐linked cyclophanes show thermally populated paramagnetic activity with a relatively large singlet‐triplet energy gap. Two enantiomers for the ortho‐cyclophanes ( 1‐NH and 1‐N ) were isolated and their chiral figure‐of‐eight macrocyclic structures were identified. The cage‐like cyclophanes 2‐NH and 3‐NH with concave surface can selectively encapsulate fullerene C70. 相似文献
13.
The effect of electric field and Al doping on the sensitivity of hexa‐peri‐hexabenzocoronene nanographene to chloropicrin 下载免费PDF全文
Akram Hosseinian Arezoo Gharachorloo Tarlan Mohazzab Lighvani Parvaneh Delir Kheirollahi Nezhad Esmail Vessally 《应用有机金属化学》2018,32(10)
It has been previously reported that the recently synthesized hexa‐peri‐hexabenzocoronene (HBC) nanographene cannot detect toxic chloropicrin (CP) gas. To overcome this problem, we examined the effect of Al doping and applying an electric field on the sensitivity of HBC towards CP gas by means of density functional theory calculations. We found that the Al‐doping process significantly increases the adsorption energy of CP gas from ?7.1 to ?39.9 kcal mol?1 but decreases the sensitivity of HBC. By applying an electric field, the HBC is polarized with two different electrostatic potentials on its different surfaces, which increases the adsorption energy. By increasing the electric field strength, the adsorption energy and electronic sensitivity of HBC are increased. We predicted that in the presence of an electric field of about ?0.025 au, HBC can act as an electronic senor or a work function‐type sensor with a short recovery time. At this field, the electrical conductivity of HBC is significantly increased on CP adsorption which generates an electrical signal. Increasing the electric field to higher intensities is not favourable because of increasing recovery times, and decreasing it to lower intensities reduces the sensitivity of HBC. 相似文献
14.
Max M. Martin Dominik Lungerich Philipp Haines Frank Hampel Norbert Jux 《Angewandte Chemie (International ed. in English)》2019,58(26):8932-8937
Single‐molecule electronic components (SMECs) are envisioned as next‐generation building blocks in quantum circuit systems. However, challenges such as the reproducibility of the electrode attachment to the individual molecules hamper their fundamental investigation. For our purpose, we introduced quasi optoelectronic electrodes (QOEs) that allow for rapid investigations of the properties and suitability of compounds for molecular electronic devices. In particular, we probed hexa‐peri‐hexabenzocoronene (HBC) as a model system for D6h‐symmetrical nanographenes, with porphyrins as QOEs attached to the periphery. We prepared selectively bis‐porphyrin‐functionalized HBCs with ortho‐, meta‐ and para‐substitution and studied their communication properties, in correlation to the geometrical alignment and size of the system, by electrochemistry and optical spectroscopy. Further insights into structure–property relationships were gained by DFT calculations and X‐ray diffraction analysis. 相似文献
15.
Dr. Christina Tönshoff Matthias Müller Prof. Dr. Tapas Kar Florian Latteyer Prof. Dr. Thomas Chassé Dr. Klaus Eichele Prof. Dr. Holger F. Bettinger 《Chemphyschem》2012,13(5):1173-1181
The doping of graphene molecules by borazine (B3N3) units may modify the electronic properties favorably. Therefore, the influence of the substitution of the central benzene ring of hexa‐peri‐hexabenzocoronene (HBC, C42H18) by an isoelectronic B3N3 ring resulting in C36B3N3H18 (B3N3HBC) is investigated by computational methods. For comparison, the isoelectronic and isosteric all‐B/N molecule B21N21H18 (termed BN) and its carbon derivative C6B18N18H18 (C6BN), obtained by substitution of a central B3N3 by a C6 ring, are also studied. The substitution of C6 in the HBC molecule by a B3N3 unit results in a significant change of the computed IR vibrational spectrum between 1400 and 1600 cm?1 due to the polarity of the borazine core. The properties of the BN molecule resemble those of hexagonal boron nitride, and substitution of the central B3N3 ring by C6 changes the computed IR vibrational spectrum only slightly. The allowed transitions to excited states associated with large oscillator strengths shift to higher energy upon going from HBC to B3N3HBC, but to lower energy upon going from BN to C6BN. The possibility of synthesis of B3N3HBC from hexaphenylborazine (HPB) using the Scholl reaction (CuCl2/AlCl3 in CS2) is investigated. Rather than the desired B3N3HBC an insoluble and X‐ray amorphous polymer P is obtained. Its analysis by IR and 11B magic angle spinning NMR spectroscopy reveals the presence of borazine units. The changes in the 11B quadrupolar coupling constant CQ, asymmetry parameter η, and isotropic chemical shift δiso(11B) with respect to HPB are in agreement with a structural model that includes B3N3HBC‐derived monomeric units in polymer P. This indicates that both intra‐ and intermolecular cyclodehydrogenation reactions take place during the Scholl reaction of HPB. 相似文献
16.
Orientational Preference of Long,Multicenter Bonds in Radical Anion Dimers: A Case Study of π‐[TCNB]22− and π‐[TCNP]22− 下载免费PDF全文
Dr. Marçal Capdevila‐Cortada Prof. Joel S. Miller Prof. Juan J. Novoa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6420-6432
The similar shape and electronic structure of the radical anions of 1,2,4,5‐tetracyanopyrazine (TCNP) and 1,2,4,5‐tetracyanobenzene (TCNB) suggest a similar relative orientation for their long, multicenter carbon?carbon bond in π‐[TCNP]22? and in π‐[TCNB]22?, in good accord with the Maximin Principle predictions. Instead, the two known structures of π‐[TCNP]22? have a D2h(θ=0°) and a C2(θ=30°) orientation (θ being the dihedral angle that determines the rotation of one radical anion relative to the other along the axis that passes through center of the two six‐membered rings). The only known π‐[TCNB]22? structure has a C2(θ=60°) orientation. The origin of these preferences was investigated for both dimers by computing (at the RASPT2/RASSCF(30,28) level) the variation with θ of the interaction energy (Eint) and the variation of the Eint components. It was found that: 1) a long, multicenter bond exists for all orientations; 2) the Eint(θ) angular dependence is similar in both dimers; 3) for all orientations the electrostatic component dominates the value of Eint(θ), although the dispersion and bonding components also play a relevant role; and 4) the Maximin Principle curve reproduces well the shape of the Eint(θ) curve for isolated dimers, although none of them reproduce the experimental preferences. Only after the (radical anion).? ??? cation+ interactions are also included in the model aggregate are the experimental data reproduced computationally. 相似文献
17.
Incorporation of Hexa‐peri‐hexabenzocoronene (HBC) into Carbazole–Benzo‐2,1,3‐thiadiazole Copolymers to Improve Hole Mobility and Photovoltaic Performance 下载免费PDF全文
Dr. Chen Gao Pei Jiang Keli Shi Di Ma Prof. Dr. Yongfang Li Prof. Dr. Gui Yu Prof. Dr. Xiaoyu Li Prof. Dr. Haiqiao Wang 《化学:亚洲杂志》2016,11(5):766-774
Hexa‐peri‐hexabenzocoronene (HBC) is a discotic‐shaped conjugated molecule with strong π–π stacking property, high intrinsic charge mobility, and good self‐assembly properties. For a long time, however, organic photovoltaic (OPV) solar cells based on HBC demonstrated low power conversion efficiencies (PCEs). In this study, two conjugated terpolymers, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5′‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT)‐ 5 HBC and PCDTBT‐ 10 HBC, were synthesized by incorporating different amounts of HBC as the third component into poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5′‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT) through Suzuki coupling polymerization. For comparison, the donor–acceptor (D –A) conjugated dipolymer PCDTBT was also synthesized to investigate the effect of HBC units on conjugated polymers. The HBC‐containing polymers exhibited higher thermal stabilities, broader absorption spectra, and lower highest‐occupied molecular orbital (HOMO) energy levels. In particular, the field‐effect mobilities were enhanced by more than one order of magnitude after the incorporation of HBC into the conjugated polymer backbone on account of increased interchain π–π stacking interactions. The bulk heterojunction (BHJ) polymer solar cells (PSCs) fabricated with the polymers as donor and PC71BM as acceptor demonstrated gradual improvement of open‐circuit voltage (VOC) and short‐circuit current (JSC) with the increase in HBC content. As a result, the PCEs were improved from 3.21 % for PCDTBT to 3.78 % for PCDTBT‐ 5 HBC and then to 4.20 % for PCDTBT‐ 10 HBC. 相似文献
18.
Xue Min Ivan A. Popov Fu‐Xing Pan Dr. Lei‐Jiao Li Eduard Matito Prof. Dr. Zhong‐Ming Sun Prof. Dr. Lai‐Sheng Wang Prof. Dr. Alexander I. Boldyrev 《Angewandte Chemie (International ed. in English)》2016,55(18):5531-5535
Antiaromaticity, as introduced in 1965, usually refers to monocyclic systems with 4n π electrons. This concept was extended to all‐metal molecules after the observation of Li3Al4? in the gas phase. However, the solid‐phase counterparts have not been documented to date. Herein, we describe a series of all‐metal antiaromatic anions, [Ln(η4‐Sb4)3]3?(Ln=La, Y, Ho, Er, Lu), which were isolated as the K([2.2.2]crypt) salts and identified by single‐crystal X‐ray diffraction. Based on the results obtained from the chemical bonding analysis, multicenter indices, and the electron‐counting rule, we conclude that the core [Ln(η4‐Sb4)3]3? fragment of the crystal has three locally π‐antiaromatic Sb4 fragments. This complex represents the first locally π‐antiaromatic all‐metal system in the solid state, which is stabilized by interactions of the three π‐antiaromatic units with the central metal atom. 相似文献
19.
Rüdiger Faust Clemens Bruhn Sara Rossi 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):o253-o255
The structure of bis(4‐tert‐butyl‐2,6‐dimethylphenyl)hexa‐1,5‐diyne‐3,4‐dione, C30H34O2, has been determined, revealing an extended s‐trans conformation of the dione and the two ynone moieties, which are shielded by the flanking methyl substituents. The structural parameters and the packing arrangement suggest little electronic delocalization between the two ynone moieties. 相似文献
20.
Ryuichi Yamaguchi Satoru Ito Byung Sun Lee Dr. Satoru Hiroto Prof. Dr. Dongho Kim Prof. Dr. Hiroshi Shinokubo 《化学:亚洲杂志》2013,8(1):178-190
We have demonstrated that the iridium‐catalyzed direct borylation of hexa‐peri‐hexabenzocoronene (HBC) enables regioselective introduction of boryl groups to the para‐, ortho‐, and meta‐substituted HBCs in high yields. The boryl groups have been transformed into various functionalities such as hydroxy, cyano, ethynyl, and amino groups. We have elucidated that the substituents significantly influence the photophysical properties of HBCs to enhance fluorescence quantum yields. DFT calculations revealed that the origin of the substituent effect is the lift in degeneracy in the frontier orbitals by an interaction with electron‐donating and electron‐withdrawing substituents at the para‐ and ortho‐positions. The change in molecular orbitals results in an increase of the transition probability from the S0→S1 states. In addition, the two‐photon absorption cross‐section values of para‐substituted HBCs are significantly larger than those of ortho‐ and meta‐substituted HBCs. 相似文献