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1.
Davide Bonifazi Gianluca Accorsi Nicola Armaroli Fayi Song Amit Palkar Luis Echegoyen Markus Scholl Paul Seiler Bernhard Jaun Franois Diederich 《Helvetica chimica acta》2005,88(7):1839-1884
We report the synthesis and physical properties of novel fullerene–oligoporphyrin dyads. In these systems, the C‐spheres are singly linked to the terminal tetrapyrrolic macrocycles of rod‐like meso,meso‐linked or triply‐linked oligoporphyrin arrays. Monofullerene–mono(ZnII porphyrin) conjugate 3 was synthesized to establish a general protocol for the preparation of the target molecules (Scheme 1). The synthesis of the meso,meso‐linked oligopophyrin–bisfullerene conjugates 4 – 6 , extending in size up to 4.1 nm ( 6 ), was accomplished by functionalization (iodination followed by Suzuki cross‐coupling) of the two free meso‐positions in oligomers 21 – 23 (Schemes 2 and 3). The attractive interactions between a fullerene and a ZnII porphyrin chromophore in these dyads was quantified as ΔG=−3.3 kcal mol−1 by variable‐temperature (VT) 1H‐NMR spectroscopy (Table 1). As a result of this interaction, the C‐spheres adopt a close tangential orientation relative to the plane of the adjacent porphyrin nucleus, as was unambiguously established by 1H‐ and 13C‐NMR (Figs. 9 and 10), and UV/VIS spectroscopy (Figs. 13–15). The synthesis of triply‐linked diporphyrin–bis[60]fullerene conjugate 8 was accomplished by Bingel cyclopropanation of bis‐malonate 45 with two C60 molecules (Scheme 5). Contrary to the meso,meso‐linked systems 4 – 6 , only a weak chromophoric interaction was observed for 8 by UV/VIS spectroscopy (Fig. 16 and Table 2), and the 1H‐NMR spectra did not provide any evidence for distinct orientational preferences of the C‐spheres. Comprehensive steady‐state and time‐resolved UV/VIS absorption and emission studies demonstrated that the photophysical properties of 8 differ completely from those of 4 – 6 and the many other known porphyrin–fullerene dyads: photoexcitation of the methano[60]fullerene moieties results in quantitative sensitization of the lowest singlet level of the porphyrin tape, which is low‐lying and very short lived. The meso,meso‐linked oligoporphyrins exhibit 1O2 sensitization capability, whereas the triply‐fused systems are unable to sensitize the formation of 1O2 because of the low energy content of their lowest excited states (Fig. 18). Electrochemical investigations (Table 3, and Figs. 19 and 20) revealed that all oligoporphyrin arrays, with or without appended methano[60]fullerene moieties, have an exceptional multicharge storage capacity due to the large number of electrons that can be reversibly exchanged. Some of the ZnII porphyrins prepared in this study form infinite, one‐dimensional supramolecular networks in the solid state, in which the macrocycles interact with each other either through H‐bonding or metal ion coordination (Figs. 6 and 7). 相似文献
2.
Dr. Regan D. Hartnell Tomoki Yoneda Hirotaka Mori Prof. Atsuhiro Osuka Prof. Dennis P. Arnold 《化学:亚洲杂志》2013,8(11):2670-2679
A meso‐bromidoplatiniobis(triphenylphosphine) η1‐organometallic porphyrin monomer was prepared by the oxidative addition of meso‐bromoZnDPP (DPP=dianion of 5,15‐diphenylporphyrin) to a platinum(0) species. The meso–meso directly linked dimeric porphyrin ( 5 ) was prepared from this monomer by silver(I)‐promoted oxidative coupling and planarized to give a triply linked dizinc(II) porphyrin dimer ( 8 ). Acidic demetallation of 8 afforded the bis(free base) 9 . Dimer 5 was demetallated then remetallated with nickel(II) to give the dinickel(II) analogue 10 , the X‐ray crystal structure of which showed a twisted molecule with ruffled, orthogonal NiDPP rings, terminated by square‐planar trans‐[Pt(PPh3)2Br] units. New compounds were fully characterized spectroscopically, and the fused diporphyrin exhibited a broad, low‐energy, near‐IR electronic absorption band near 1100 nm. Electrochemical measurements of this series indicate that the organometallic fragment is a strong electron donor towards the porphyrin ring. The triply linked organometallic diporphyrin has a substantially lowered first one‐electron oxidation potential (?0.35 V versus the ferrocene/ferrocenium couple (Fc/Fc+)) and a narrow HOMO–LUMO gap of 0.96 V. Solutions prepared for NMR spectroscopy slowly decompose with degradation of the signals, which is attributed to partial oxidation to the cation radical. This paramagnetic species can be reduced in situ by hydrazine to restore the NMR spectrum to its former appearance. The combined influence of the two [Pt(PPh3)2Br] electron‐donating substituents is sufficient to make dimer 5 too aerobically unstable to allow further elaboration. 相似文献
3.
Chihiro Maeda Pyosang Kim Sung Cho Jong Kang Park Jong Min Lim Dongho Kim Prof. Dr. Josh Vura‐Weis Michael R. Wasielewski Prof. Dr. Hiroshi Shinokubo Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(17):5052-5061
meso‐Triazolyl‐appended ZnII–porphyrins were readily prepared by CuI‐catalyzed 1,3‐dipolar cycloaddition of benzyl azide to meso‐ethynylated ZnII–porphyrin (click chemistry). In noncoordinating CHCl3 solvent, spontaneous assembly occurred to form tetrameric array ( 3 )2 from meso–meso‐linked diporphyrins 3 , and dodecameric porphyrin squares ( 4 )4 and ( 5 )4 from the L ‐shaped meso–meso‐linked triporphyrins 4 and 5 . The structures of these assemblies were examined by 1H NMR spectra, absorption spectra, and their gel permeation chromatography (GPC) retention time. Furthermore, the structures of the dodecameric porphyrin squares ( 4 )4 and ( 5 )4 were probed by small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) measurements in solution using a synchrotron source. Excitation‐energy migration processes in these assemblies were also investigated in detail by using both steady‐state and time‐resolved spectroscopic methods, which revealed efficient excited‐energy transfer (EET) between the meso–meso‐linked ZnII–porphyrin units that occurred with time constants of 1.5 ps?1 for ( 3 )2 and 8.8 ps?1 for ( 5 )4. 相似文献
4.
Directly meso‐meso, β‐β, β‐β triply linked porphyrin arrays are exceptional π‐conjugated molecules exhibiting remarkably red‐shifted absorption bands extending deeply in the IR region. In order to determine the effective conjugated length (ECL), we embarked on the synthesis of the porphyrin tapes far beyond the 12‐mer, which is the longest we have prepared so far. In this study, to find the compromise between the feasibility of the meso‐meso coupling reaction up to longer arrays and the sufficient solubility and chemical stability of the resultant porphyrin tapes, we prepared hybrid meso‐meso linked porphyrin arrays BOn up to 24‐mer, which have two different aryl groups, a 2,4,6‐tris(3,5‐di‐tert‐butylphenoxy) phenyl group (Ar1) and a 3,5‐dioctyloxy phenyl group (Ar2). All these arrays were effectively converted into the corresponding triply linked porphyrin tapes TBOn by oxidation with DDQ‐Sc(OTf)3. Importantly, the low energy Q‐band‐like absorption bands of TBOn are progressively red‐shifted with an increase in the number of porphyrins n until 16 but the red‐shift is saturated at n=16, indicating the ECL of the porphyrin tape to be around 14–16. The regularly introduced meso‐aryl bulky substituents impose facial encumbrance, hence leading to the effective suppression of π–π interactions as well as improvement of the chemical stabilities of TBOn . 相似文献
5.
Tanaka T Lee BS Aratani N Yoon MC Kim D Osuka A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(51):14400-14412
Hybrid porphyrin tapes 3 and 4 , consisting of a mixture of 3,5‐di‐tert‐butylphenyl‐substituted donor‐type ZnII–porphyrins and pentafluorophenyl‐substituted acceptor‐type ZnII–porphyrins, were prepared by a synthetic route involving cross‐condensation reaction of a NiII–porphyrinyldipyrromethane and pentafluorophenyldipyrromethane with pentafluorobenzaldehyde followed by appropriate demetalation, remetalation, and oxidative ring‐closure reaction. The NiII‐substituted porphyrin tapes 5 (Ni‐Zn‐Ni) and 6 (Ni‐H2‐Ni) were also prepared through similar routes. The hybrid porphyrin tapes 3 and 4 are more soluble and more stable than normal porphyrin tapes 1 and 2 consisting of only donor‐type ZnII–porphyrins. The solid‐state and crystal packing structures of 3 , 4 , and 5 were elucidated by single‐crystal X‐ray diffraction analysis. Singly meso–meso‐linked hybrid porphyrin arrays 12 and 14 exhibit redox potentials that roughly correspond to each constituent porphyrin segments, while the redox potentials of the hybrid porphyrin tapes 3 and 4 are positively shifted as a whole. The two‐photon absorption (TPA) values of 1–6 were measured by using a wavelength‐scanning open aperture Z‐scan method and found to be 1900, 21 000, 2200, 27 000, 24 000, and 26 000 GM, respectively. These results illustrate an important effect of elongation of π‐electron conjugation for the enhancement of TPA values. The hybrid porphyrin tapes show slightly larger TPA values than the parent ones. 相似文献
6.
meso‐Free BIII 5,10‐bis(p‐dimethylaminophenyl)subporphyrins were synthesized. They display red‐shifted absorption and fluorescence spectra, bathochromic behaviors in polar solvents, a high fluorescence quantum yield (ΦF=0.57), and a small HOMO–LUMO gap mainly due to destabilized HOMO as compared with meso‐free BIII 5,10‐diphenylsubporphyrin. This subporphyrin serves as a nice precursor of various meso‐substituted BIII subporphyrins such as BIII meso‐nitrosubporphyrin, BIII meso‐aminosubporphyrin, and meso‐meso’ linked BIII azosubporphyrin dimer. Reactions of meso‐free BIII subporphyrins with NBS or bis(2,4,6‐trimethylpyridine)bromonium hexafluorophosphate gave meso‐meso′ linked subporphyrin dimers, often as a major product along with meso‐bromosubporphyrins. 相似文献
7.
Shota Ooi Dr. Takayuki Tanaka Kyu Hyung Park Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2016,55(22):6535-6539
The oxidation of 10–10′ singly linked corrole dimers with DDQ at low concentration in CHCl3 afforded meso–meso, β–β, β–β triply linked 2H‐corrole dimers (with two inner NH groups in each corrole unit), which exhibited characteristic 1H NMR and absorption spectra attributable to their nonaromatic electronic networks. These 2H‐corrole dimers were reduced with NaBH4 to aromatic 3H‐corrole dimers, which were unstable and easily oxidized back to the 2H‐corrole dimers upon exposure to air. Bis(zinc(II)) complexes of the 2H‐corrole dimers were synthesized and characterized as rare examples of nonaromatic zinc(II) corrole complexes. 相似文献
8.
Shota Ooi Takayuki Tanaka Kyu Hyung Park Dongho Kim Atsuhiro Osuka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(22):6645-6649
The oxidation of 10–10′ singly linked corrole dimers with DDQ at low concentration in CHCl3 afforded meso–meso, β–β, β–β triply linked 2H‐corrole dimers (with two inner NH groups in each corrole unit), which exhibited characteristic 1H NMR and absorption spectra attributable to their nonaromatic electronic networks. These 2H‐corrole dimers were reduced with NaBH4 to aromatic 3H‐corrole dimers, which were unstable and easily oxidized back to the 2H‐corrole dimers upon exposure to air. Bis(zinc(II)) complexes of the 2H‐corrole dimers were synthesized and characterized as rare examples of nonaromatic zinc(II) corrole complexes. 相似文献
9.
Hirotaka Mori Taeyeon Kim Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《化学:亚洲杂志》2016,11(9):1454-1463
New hybrid porphyrin tapes comprising meso‐3,5‐di‐tert‐butylphenyl‐substituted ZnII‐porphyrins ( D ) and meso‐pentafluorophenyl‐substituted ZnII‐porphyrins ( A ) were synthesized via cross‐condensation of meso‐formyl porphyrins 1 , 5 , and 9 with oligopyrromethanes 2 and 6 as key steps. These hybrid tapes exhibit improved solubilities and enhanced chemical stability as compared with original Dn porphyrin tapes, and all display remarkably coplanar structures favorable for π‐conjugation. The absorption spectrum of ADDA displays Q‐like bands at 1400 and 1657 nm with a vibronic structure characteristic of porphyrinoids. The cyclic voltammograms exhibited positively shifted oxidation and reduction waves in the order of DDD < DAD < ADA < AAA . Tetrameric tape ADDA displays five reversible waves in a narrow range of 1.13 V. Two‐photon absorption (TPA) measurement confirmed that the π‐conjugation path is extended from 12 to ADDA and the molecular polarizability of ADA is larger than that of AAA . 相似文献
10.
Akito Nakai Dr. Takayuki Tanaka Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(20):e202200328
Directly meso-meso linked porphyrin-tetrabromo[36]octaphyrin-porphyrin hybrid trimer 10 was successfully synthesized via acid-catalyzed condensation reaction and subsequent oxidation. ZnII-metalation of 10 induced transannular meso-meso bond formation to give Möbius aromatic bis-ZnII octaphyrin 11 , which was oxidized by DDQ/Sc(OTf)3 to provide fully conjugated porphyrin-[36]octaphyrin-porphyrin hybrid tape 12 as the first example of porphyrin tape exhibiting Möbius aromaticity. Hybrid tape 12 displays significantly red-shifted absorption and small electrochemical HOMO-LUMO gap, indicating the effective conjugation through the whole chromophores. 相似文献
11.
Directly 2,12‐ and 2,8‐Linked ZnII Porphyrin Oligomers: Synthesis,Optical Properties,and Coherence Lengths 下载免费PDF全文
Dr. Hua‐Wei Jiang Taeyeon Kim Dr. Takayuki Tanaka Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):83-87
Directly 2,12‐ and 2,8‐linked ZnII porphyrin oligomers were prepared from 2,12‐ and 2,8‐diborylated ZnII porphyrin by a cross platinum‐induced coupling with a 2‐borylated ZnII porphyrin end unit followed by a triphenylphosphine (PPh3)‐mediated reductive elimination. Comparative studies on the steady‐state absorption and fluorescence spectra and the fluorescence lifetimes led to a conclusion that the exciton in the S1 state is delocalized over approximately four and two ZnII porphyrin units for 2,12‐ and 2,8‐linked ZnII porphyrin arrays, respectively. 相似文献
12.
Our synthetic attempts for the preparation oligo‐ and polyporphyrin arrays were reviewed in comparison with recent accomplishment in the related field. Especially, the synthesis and structural characteristics of huge monodisperse meso‐meso linked porphyrin arrays with multidimensional architectures were focused. The AgI‐promoted meso‐meso coupling reaction of 5,15‐diaryl and 5,10,15‐triaryl ZnII‐porphyrins is advantageous in light of its high regioselectivity, as well as its easy extension to large porphyrin arrays. When applied to 1,4‐phenylene‐bridged linear porphyrin substrates, the coupling reaction gave three‐dimensionally arranged windmill‐shaped and grid‐shaped porphyrin arrays. The meso‐meso coupling doubling reaction was repeated up to the synthesis of a discrete 128‐mer. During these attempts, many porphyrin arrays were isolated in a discrete form by repetitive gel‐permeation chromatography and, interestingly, all the arrays exhibited high solubility in common organic solvents in spite of their giant molecular size. Furthermore, the AgI‐promoted coupling reaction was extended to the preparation of long polyporphyrinylenes under slightly modified conditions by either adding N,N‐dimethylacetamide (DMA) or heating slightly. 相似文献
13.
Akihiko Tsuda Atsuhiro Osuka 《Journal of inclusion phenomena and macrocyclic chemistry》2001,41(1-4):77-81
The AgI-promoted oxidative meso-meso coupling reaction of 5,15-diaryl ZnII-porphyrins is advantageous in light of its high regioselectivity as well as its easy extension to large porphyrin arrays. Linear meso-meso linked porphyrin 128-mer and three-dimensionally arranged grid porphyrin 48-mer were isolated in a discrete form by repetitive oxidation reaction and subsequent gel-permeation chromatography (GPC)-HPLC. 5,15-Diaryl CuII-, NiII-, and PdII-porphyrins were converted to meso- doubly-linked diporphyrins by oxidation with(p-BrC6H4)3NSbCl6. End-aryl-capped meso-meso linked CuII-, NiII-, and PdII- diporphyrins were converted to completely fused meso-meso - -triply-linked diporphyrins through the oxidative ring closure (ODRC) reaction with (p-BrC6H4)3NSbCl6. Finally, we found that ScIII-catalyzed oxidation with DDQ gave a very efficient ODRC reaction and hence allowed the synthesis of triply-linked oligoporphyrins up to 12-mer. 相似文献
14.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(40):12490-12494
A powerful and concise synthesis of directly linked porphyrin‐BODIPY hybrids has been demonstrated, which consists of condensation of directly linked meso ‐pyrroyl NiII‐porphyrin with arylaldehyde, oxidation with p ‐chloranil, and complexation with BF3⋅Et2O. Synthesized hybrids include porphyrin dimer 6Ni , trimers 8Ni , 9Ni , tetramer 12Ni , pentamer 16Ni , hexamer 13Ni , and nonamers 17Ni and 18Ni . The structures of 6Ni , 9Ni and 12Ni were unambiguously confirmed by X‐ray diffraction analysis. Some NiII porphyrins were effectively converted to the corresponding ZnII porphryins. In these hybrids, the pigments are three‐dimensionally arranged with a face‐to‐face dimeric porphyrin unit in a well‐defined manner, featuring their potential as light‐harvesting antenna and functional hosts. 相似文献
15.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(40):12485-12489
A meso–meso β‐β β‐β triply linked subporphyrin dimer 6 was synthesized by stepwise reductive elimination of β‐to‐β doubly PtII‐bridged subporphyrin dimer 9 . Dimer 6 was characterized by spectroscopic and electrochemical measurements, theoretical calculations, and picosecond time‐resolved transient absorption spectroscopy. X‐ray diffraction analysis reveals that 6 has a bowl‐shaped structure with a positive Gaussian curvature. Despite the curved structure, 6 exhibits a remarkably red‐shifted absorption band at 942 nm and a small electrochemical HOMO–LUMO gap (1.35 eV), indicating an effectively conjugated π‐electronic network. 相似文献
16.
Dr. Keisuke Fujimoto Daiki Shimizu Prof. Dr. Tadashi Mori Yuanyuan Li Dr. Mingbo Zhou Prof. Dr. Jianxin Song Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1711-1715
Oxidation of β-to-β directly linked and sulfur-bridged meso-amino NiII-porphyrin dimers with PbO2 gave helical tetrapyrrin (biliverdin analogue)-fused NiII-porphyrins. These ring cleaving reactions differ markedly from the previously reported oxidation of a β–β linked NiII-porphyrin dimer carrying one amino group, which gave an azepine-fused porphyrin dimer. The tetrapyrrin-fused NiII-porphyrins display intense NIR absorption bands at 1200–1400 nm and reversible redox processes because of the highly π-conjugated networks and rigid structures. These tetrapyrrin-fused NiII-porphyrins were separated to stable enantiomers, which showed clear Cotton effects in their CD spectra with Δϵ of 102 order. 相似文献
17.
A Benzene‐1,3,5‐Triaminyl Radical Fused with ZnII‐Porphyrins: Remarkable Stability and a High‐Spin Quartet Ground State 下载免费PDF全文
Daiki Shimizu Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2018,57(14):3733-3736
A benzene‐1,3,5‐triaminyl radical fused with three ZnII‐porphyrins was synthesized through a three‐fold oxidative fusion reaction of 1,3,5‐tris(ZnII‐porphyrinylamino)benzene followed by oxidation with PbO2 as key steps. This triaminyl radical has been shown to possess a quartet ground state with a doublet–quartet energy gap of 3.1 kJ mol?1 by superconducting quantum interference device (SQUID) studies. Despite its high‐spin nature, this triradical is remarkably stable, which allows its separation and recrystallization under ambient conditions. Moreover, this triradical can be stored as a solid for more than one year without serious deterioration. The high stability of the triradical is attributed to effective spin delocalization over the porphyrin segments and steric protection at the nitrogen centers and the porphyrin meso positions. 相似文献
18.
Control of Conformation and Chirality of Nonplanar π‐Conjugated Diporphyrins Using Substituents and Axial Ligands 下载免费PDF全文
Satoru Ito Prof. Dr. Satoru Hiroto Prof. Dr. Naoki Ousaka Prof. Dr. Eiji Yashima Prof. Dr. Hiroshi Shinokubo 《化学:亚洲杂志》2016,11(6):936-942
Nonplanar conformations of pyrazine‐fused ZnII diporphyrins could be controlled by the choice of the meso‐aryl substituents and an axial ligand on the central metals. ZnII diporphyrins bearing sterically demanding meso‐aryl groups with ortho‐substituents led to a twisted chiral D2 conformation, while an achiral C2h form was preferred in the case of aryl groups without ortho‐substituents. Helical chirality induction on ZnII diporphyrins in the twisted conformation was achieved by controlling their handedness of the molecular twist through coordination of optically active 1‐phenethylamine. 相似文献
19.
Treatment of a meso‐diarylporphyrin with PhI(OAc)2 in the presence of BF3 ? OEt2 and propionic acid affords the corresponding porphyrinquinone in a high yield (91%). A novel quinone derived from meso‐meso β–β doubly‐fused diporphyrin was obtained as the sole byproduct (16% yield), which exhibits strong panchromatic absorption between 300 and 1000 nm. It has a low HOMO‐LUMO gap owing to expanded and low‐symmetry π‐planes. 相似文献
20.
Homoleptic Zinc(II) Complexes Based on 4′‐(2‐Thienyl)‐terpyridine: Preparation,Structures, and Properties 下载免费PDF全文
The homoleptic complexes ZnII(4′‐(2‐(5‐R‐thienyl))‐terpyridine)2(ClO4)2 [R = hydrogen ( 1 ), bromo ( 2 ), methyl ( 3 ), and methoxy ( 4 )] were prepared. Their structures were determined by single‐crystal X‐ray diffraction analyses, and further characterized by high resolution mass, infrared spectra (IR), and elemental analyses. Single crystal X‐ray diffraction analysis showed that ZnII ions in the complexes are both six‐coordinate with N6 coordination sphere, displaying distorted octahedral arrangements. The absorption and emission spectra of the homoleptic ZnII complexes were investigated and compared to those of the parent complex ZnII(4′‐(2‐thienyl))‐terpyridine)2(ClO4)2. The UV/Vis absorption spectra showed that the complexes all exhibit strong absorption component in UV region, moreover, complex 4 has an absorption component in the visible region. Thus, the photocatalytic activities of the complexes in degradation of organic dyes were investigated under UV and visible irradiation. 相似文献