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1.
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
2.
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
3.
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
4.
Shunichi Fukuzumi Prof. Dr. Hiroaki Kotani Dr. Tomoyoshi Suenobu Dr. Seungwoo Hong Yong‐Min Lee Dr. Wonwoo Nam Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(1):354-361
The effects of axial ligands on electron‐transfer and proton‐coupled electron‐transfer reactions of mononuclear nonheme oxoiron(IV) complexes were investigated by using [FeIV(O)(tmc)(X)]n+ ( 1 ‐X) with various axial ligands, in which tmc is 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane and X is CH3CN ( 1 ‐NCCH3), CF3COO? ( 1 ‐OOCCF3), or N3? ( 1 ‐N3), and ferrocene derivatives as electron donors. As the binding strength of the axial ligands increases, the one‐electron reduction potentials of 1 ‐X (Ered, V vs. saturated calomel electrode (SCE)) are more negatively shifted by the binding of the more electron‐donating axial ligands in the order of 1 ‐NCCH3 (0.39) > 1 ‐OOCCF3 (0.13) > 1 ‐N3 (?0.05 V). Rate constants of electron transfer from ferrocene derivatives to 1 ‐X were analyzed in light of the Marcus theory of electron transfer to determine reorganization energies (λ) of electron transfer. The λ values decrease in the order of 1 ‐NCCH3 (2.37) > 1 ‐OOCCF3 (2.12) > 1 ‐N3 (1.97 eV). Thus, the electron‐transfer reduction becomes less favorable thermodynamically but more favorable kinetically with increasing donor ability of the axial ligands. The net effect of the axial ligands is the deceleration of the electron‐transfer rate in the order of 1 ‐NCCH3 > 1 ‐OOCCF3 > 1 ‐N3. In sharp contrast to this, the rates of the proton‐coupled electron‐transfer reactions of 1 ‐X are markedly accelerated in the presence of an acid in the opposite order: 1 ‐NCCH3 < 1 ‐OOCCF3 < 1 ‐N3. Such contrasting effects of the axial ligands on the electron‐transfer and proton‐coupled electron‐transfer reactions of nonheme oxoiron(IV) complexes are discussed in light of the counterintuitive reactivity patterns observed in the oxo transfer and hydrogen‐atom abstraction reactions by nonheme oxoiron(IV) complexes (Sastri et al. Proc. Natl. Acad. Sci. U.S.A. 2007 , 104, 19 181–19 186). 相似文献
5.
Hirotaka Mori Dr. Takayuki Tanaka Dr. Naoki Aratani Byung Sun Lee Pyosang Kim Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《化学:亚洲杂志》2012,7(8):1811-1816
Hexakis(pentafluorophenyl)‐substituted meso–meso‐linked ZnII–diporphyrin ( 9 ), which was prepared by the acid‐catalyzed cross‐condensation of 1,1,2,2‐tetrapyrroethane ( 5 ) with dipyrromethane dicarbinol ( 6 ), was converted into meso–meso,β‐β,β‐β triply linked ZnII–diporphyrin 3 by oxidation with 2,3‐dichloro‐5,6‐dicyanobenzoquinone (DDQ) and Sc(OTf)3. Beside the red‐shifted absorption spectrum and split first oxidation potential that are common to the triply‐linked ZnII–diporphyrins, diporphyrin 3 exhibited considerably improved chemical stability owing to a lowered HOMO and good solubility in common organic solvents. The two‐photon absorption (TPA) cross‐section and S1‐state lifetime of compound 3 were 1700 GM and 3.3 ps, respectively. 相似文献
6.
Fudong Chen Prof. Shirong Wang Prof. Yin Xiao Feng Peng Nonglin Zhou Dr. Lei Ying Prof. Xianggao Li 《化学:亚洲杂志》2018,13(10):1335-1341
Two alcohol‐soluble electron‐transport materials (ETMs), diphenyl(4‐(1‐phenyl‐1H‐benzo[d]imidazol‐2‐yl)phenyl)phosphine oxide (pPBIPO) and (3,5‐bis(1‐phenyl‐1H‐benzo[d]imidazol‐2‐yl)phenyl)diphenylphosphine oxide (mBPBIPO), have been synthesized. The physical properties of these ETMs were investigated and they both exhibited high electron‐transport mobilities (1.67×10?4 and 2.15×10?4 cm2 V?1 s?1), high glass‐transition temperatures (81 and 110 °C), and low LUMO energy levels (?2.87 and ?2.82 eV, respectively). The solubility of PBIPO in n‐butyl alcohol was more than 20 mg mL?1, which meets the requirement for fully solution‐processed organic light‐emitting diodes (OLEDs). Fully solution‐processed green‐phosphorescent OLEDs were fabricated by using alcohol‐soluble PBIPO as electron‐transport layers (ETLs), and they exhibited high current efficiencies, power efficiencies, and external quantum efficiencies of up to 38.43 cd A?1, 26.64 lm W?1, and 10.87 %, respectively. Compared with devices that did not contain PBIPO as an ETM, the performance of these devices was much improved, which indicated the excellent electron‐transport properties of PBIPO. 相似文献
7.
Leonardo De Boni Ruben D. Fonseca Kleber R. A. Cardoso Isabel Grova Leni Akcelrud Daniel S. Correa Cleber R. Mendonça 《Journal of Polymer Science.Polymer Physics》2014,52(11):747-754
Fluorene‐based polymer derivatives are promising materials for organic electronic devices because of their photoluminescence and electroluminescence, good film‐forming ability, and favorable chemical and thermal properties. Although optical properties of polyfluorene have already been reported, most of the studies focused on the linear optical properties, whereas nonlinear optical characteristics have only recently received more detailed attention. Here, we report on two polyfluorene derivatives, poly(9,9′‐n‐dihexyl‐2,7‐fluorenediyl) (LaPPS 10) and poly(9,9′‐n‐dihexyl‐2,7‐fluorene‐diyl‐vinylene) (LaPPS 38), which present intense nonlinear absorption and fluorescence. Two‐photon absorption cross‐section properties of both polymers were characterized in the spectral range from 500 nm up to 900 nm, reaching peak values around 2000 Göppert Mayer units. Optical limiting behavior and two‐photon‐induced fluorescence of both polymers have also been investigated. Furthermore, the first molecular hyperpolarizability of the polymers was also studied using hyper‐Rayleigh scattering. In addition, the three‐photon absorption (3PA) spectra of both materials were also investigated, and 3PA cross‐section values in the order of 1 × 10?78 cm6 s2 photon?2 were observed. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 747–754 相似文献
8.
Peiyang Gu Xufeng Xu Feng Zhou Tingting Zhao Gaojie Ye Gaoyan Liu Qinghua Xu Jianfeng Ge Qingfeng Xu Jianmei Lu 《中国化学》2014,32(3):205-211
Four 1,8‐naphthalimide hydrazone molecules with different electron‐donating groups have been applied in the study of linear and nonlinear optical (NLO) properties. These compounds showed strong green emission in solution. Their NLO properties such as two‐photon absorption (TPA) behavior with femtosecond laser pulses ca. 800 nm and excited‐state absorption (ESA) behavior with nanosecond laser pulses at 532 nm were investigated. Compound 4 presented the largest two‐photon cross section (550 GM) among them due to two factors: the conjugated length of compound 4 is the longest and the electron‐donating ability of compound 4 is the strongest. Different from TPA behavior, compound 2 showed the best nonlinear absorption properties at 532 nm and its nonlinear absorption coefficient and third‐order nonlinear optical susceptibilities χ (3) were up to 1.41×10?10 MKS and 4.65×10?12 esu, respectively. Through the modification of the structure, the nonlinear optical properties of these compounds at different wavelengths (532 and 800 nm) were well tuned. The great broad‐band nonlinear optical properties indicate hydrazones are good candidates for organic nonlinear optical absorption materials. 相似文献
9.
trans/cis‐Isomerization of Fluorene‐Bridged Azo Chromophore with Significant Two‐Photon Absorbability at Near‐Infrared Wavelength
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Prof. Dr. Chih‐Chien Chu Ya‐Chi Chang Bo‐Kai Tsai Prof. Dr. Tzu‐Chau Lin Prof. Dr. Ja‐Hon Lin Prof. Dr. Vincent K. S. Hsiao 《化学:亚洲杂志》2014,9(12):3390-3396
Azo‐containing materials have been proven to possess second‐order nonlinear optical (NLO) properties, but their third‐order NLO properties, which involves two‐photon absorption (2PA), has rarely been reported. In this study, we demonstrate a significant 2PA behavior of the novel azo chromophore incorporated with bilateral diphenylaminofluorenes (DPAFs) as a π framework. The electron‐donating DPAF moieties cause a redshifted π–π* absorption band centered at 470 nm, thus allowing efficient blue‐light‐induced trans‐to‐cis photoisomerization with a rate constant of 2.04×10?1 min?1 at the photostationary state (PSS). The open‐aperture Z‐scan technique that adopted a femtosecond (fs) pulse laser as excitation source shows an appreciably higher 2PA cross‐section for the fluorene‐derived azo chromophore than that for common azobenzene dyes at near‐infrared wavelength (λex=800 nm). Furthermore, the fs 2PA response is quite uniform regardless of the molecular geometry. On the basis of the computational modeling, the intramolecular charge‐transfer (ICT) process from peripheral diphenylamines to the central azo group through a fluorene π bridge is crucial to this remarkable 2PA behavior. 相似文献
10.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(48):15481-15485
Iron(III)‐5,15‐diphenylporphyrin and several derivatives were accommodated by HasA, a heme acquisition protein secreted by Pseudomonas aeruginosa , despite possessing bulky substituents at the meso position of the porphyrin. Crystal structure analysis revealed that the two phenyl groups at the meso positions of porphyrin extend outside HasA. It was shown that the growth of P. aeruginosa was inhibited in the presence of HasA coordinating the synthetic porphyrins under iron‐limiting conditions, and that the structure of the synthetic porphyrins greatly affects the inhibition efficiency. 相似文献
11.
N‐Annulated Perylene‐Substituted and Fused Porphyrin Dimers with Intense Near‐Infrared One‐Photon and Two‐Photon Absorption
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Dr. Jie Luo Sangsu Lee Minjung Son Dr. Bin Zheng Prof. Kuo‐Wei Huang Qingbiao Qi Wangdong Zeng Dr. Gongqiang Li Prof. Dongho Kim Prof. Jishan Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3708-3715
Fusion of two N‐annulated perylene (NP) units with a fused porphyrin dimer along the S0–S1 electronic transition moment axis has resulted in new near‐infrared (NIR) dyes 1 a / 1 b with very intense absorption (ε>1.3×105 M ?1 cm?1) beyond 1250 nm. Both compounds displayed moderate NIR fluorescence with fluorescence quantum yields of 4.4×10?6 and 6.0×10?6 for 1 a and 1 b , respectively. The NP‐substituted porphyrin dimers 2 a / 2 b have also been obtained by controlled oxidative coupling and cyclodehydrogenation, and they showed superimposed absorptions of the fused porphyrin dimer and the NP chromophore. The excited‐state dynamics of all of these compounds have been studied by femtosecond transient absorption measurements, which revealed porphyrin dimer‐like behaviour. These new chromophores also exhibited good nonlinear optical susceptibility with large two‐photon absorption cross‐sections in the NIR region due to extended π‐conjugation. Time‐dependent density functional theory calculations have been performed to aid our understanding of their electronic structures and absorption spectra. 相似文献
12.
Yaeun Kang Hui Chen Dr. Yu Jin Jeong Wenzhen Lai Dr. Eun Hae Bae Sason Shaik Prof. Dr. Wonwoo Nam Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(39):10039-10046
The proximal axial ligand in heme iron enzymes plays an important role in tuning the reactivities of iron(IV)‐oxo porphyrin π‐cation radicals in oxidation reactions. The present study reports the effects of axial ligands in olefin epoxidation, aromatic hydroxylation, alcohol oxidation, and alkane hydroxylation, by [(tmp)+. FeIV(O)(p‐Y‐PyO)]+ ( 1 ‐Y) (tmp=meso‐tetramesitylporphyrin, p‐Y‐PyO=para‐substituted pyridine N‐oxides, and Y=OCH3, CH3, H, Cl). In all of the oxidation reactions, the reactivities of 1 ‐Y are found to follow the order 1 ‐OCH3 > 1 ‐CH3 > 1 ‐H > 1 ‐Cl; negative Hammett ρ values of ?1.4 to ?2.7 were obtained by plotting the reaction rates against the σp values of the substituents of p‐Y‐PyO. These results, as well as previous ones on the effect of anionic nucleophiles, show that iron(IV)‐oxo porphyrin π‐cation radicals bearing electron‐donating axial ligands are more reactive in oxo‐transfer and hydrogen‐atom abstraction reactions. These results are counterintuitive since iron(IV)‐oxo porphyrin π‐cation radicals are electrophilic species. Theoretical calculations of anionic and neutral ligands reproduced the counterintuitive experimental findings and elucidated the root cause of the axial ligand effects. Thus, in the case of anionic ligands, as the ligand becomes a better electron donor, it strengthens the FeO? H bond and thereby enhances its H‐abstraction activity. In addition, it weakens the Fe?O bond and encourages oxo‐transfer reactivity. Both are Bell–Evans–Polanyi effects, however, in a series of neutral ligands like p‐Y‐PyO, there is a relatively weak trend that appears to originate in two‐state reactivity (TSR). This combination of experiment and theory enabled us to elucidate the factors that control the reactivity patterns of iron(IV)‐oxo porphyrin π‐cation radicals in oxidation reactions and to resolve an enigmatic and fundamental problem. 相似文献
13.
14.
The synthesis, characterization, and redox and spectral properties of the meso‐5,10,15,20‐tetrakis(2′‐chlorobenzoquinolin‐3′‐yl)porphyrin are reported. The synthesis of the porphyrin was performed by following the modified Lindsey procedure, and its zinc(II) derivative was prepared by using the conventional method. The electronic properties of the compound were investigated by cyclic voltammetry and spectroscopy. This compound shows unusual redox behavior with difficulty in oxidation and ease of reduction compared to tetraphenylporphyrin. 相似文献
15.
Kei Ohkubo Dr. Rachel Garcia Paul J. Sintic Dr. Tony Khoury Dr. Maxwell J. Crossley Prof. Dr. Karl M. Kadish Prof. Dr. Shunichi Fukuzumi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10493-10503
The site of electron‐transfer reduction of AuPQ+ (PQ=5,10,15,20‐tetrakis(3,5‐di‐tert‐butylphenyl)quino‐xalino[2, 3?b′]porphyrin) and AuQPQ+ (QPQ=5,10,15,20‐tetrakis(3,5‐di‐tert‐butylphenyl)bisquinoxalino[2,3‐b′:12,13‐b′′]porphyrin) is changed from the AuIII center to the quinoxaline part of the PQ macrocycle in the presence of Sc3+ in benzonitrile because of strong binding of Sc3+ to the two nitrogen atoms of the quinoxaline moiety. Strong binding of Sc3+ to the corresponding nitrogen atoms on the quinoxaline unit of ZnPQ also occurs for the neutral form. The effects of Sc3+ on the photodynamics of an electron donor–acceptor compound containing a linked ZnII and AuIII porphyrin ([ZnPQ–AuPQ]PF6) have been examined by femto‐ and nanosecond laser flash photolysis measurements. The observed transient absorption bands at 630 and 670 nm after laser pulse irradiation in the absence of Sc3+ in benzonitrile are assigned to the charge‐shifted (CS) state (ZnPQ . +–AuPQ). The CS state decays through back electron transfer (BET) to the ground state rather than to the triplet excited state. The BET rate was determined from the disappearance of the absorption band due to the CS state. The decay of the CS state obeys first‐order kinetics. The CS lifetime was determined to be 250 ps in benzonitrile. Addition of Sc3+ to a solution of ZnPQ–AuPQ+ in benzonitrile caused a drastic lengthening of the CS lifetime that was determined to be 430 ns, a value 1700 times longer than the 250 ps lifetime measured in the absence of Sc3+. Such remarkable prolongation of the CS lifetime in the presence of Sc3+ results from a change in the site of electron transfer from the AuIII center to the quinoxaline part of the PQ macrocycle when Sc3+ binds to the quinoxaline moiety, which decelerate BET due to a large reorganization energy of electron transfer. The change in the site of electron transfer was confirmed by ESR measurements, redox potentials, and UV/Vis spectra of the singly reduced products. 相似文献
16.
The structures and second‐order nonlinear optical (NLO) properties of a series of chlorobenzyl‐o‐carboranes derivatives ( 1 – 12 ) containing different push‐pull groups have been studied by density functional theory (DFT) calculation. Our theoretical calculations show that the static first hyperpolarizability (βtot) values gradually increase with increasing the π‐conjugation length and the strength of electron donor group. Especially, compound 12 exhibits the largest βtot (62.404×10?30 esu) by introducing tetrathiafulvalene (TTF), which is about 76 times larger than that of compound 1 containing aryl. This means that the appropriate structural modification can substantially increase the first hyperpolarizabilities of the studied compounds. For the sake of understanding the origin of these large NLO responses, the frontier molecular orbitals (FMOs), electron density difference maps (EDDMs), orbital energy and electronic transition energy of the studied compounds are analyzed. According to the two‐state model, the lower transition energy plays an important role in increasing the first hyperpolarizability values. This study may evoke possible ways to design preferable NLO materials. 相似文献
17.
Yongsheng Mi Pengxia Liang Zhaokui Jin Dr. Dong Wang Prof. Dr. Zhou Yang 《Chemphyschem》2013,14(18):4102-4108
A series of asymmetric triphenylene derivatives containing typical D –π–A structures is successfully synthesized by means of [2+2] cycloaddition–cycloreversion click reactions. The photophysical and electrochemical properties, as well as the click reactions, are characterized by means of UV/Vis absorption spectroscopy, cyclic voltammetry, and DFT modulations. In addition, the third‐order nonlinear properties, including the nonlinear absorption and the nonlinear susceptibilities, are investigated by using Z‐scan techniques. A typical reverse saturable absorption–saturable absorption behavior is observed for the third‐order nonlinear absorption, with the third‐order nonlinear susceptibilities of the compounds being 1.05×10?12, ?1.50×10?12, and ?0.52×10?12 esu, respectively. 相似文献
18.
Direct meso‐Alkynylation of Metalloporphyrins Through Gold Catalysis for Hemoprotein Engineering
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Dr. Alexander Nierth Prof. Michael A. Marletta 《Angewandte Chemie (International ed. in English)》2014,53(10):2611-2614
A method was developed for the direct functionalization of metalloporphyrins at the methine protons (meso positions) to yield asymmetric alkynylated derivatives by using gold catalysis and hypervalent iodine reagents. This single‐step procedure was applied to b‐type heme and the product was incorporated into a gas‐sensor heme protein. The terminal alkyne allows fluorophore labeling through copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC). Hemoproteins with this type of engineered cofactor have several potential applications in labeling and imaging technologies. Additionally, the alkyne provides a handle for modulating porphyrin electron density, which affects cofactor redox potential and ligand affinity. This method will be helpful for investigating the chemistry of natural heme proteins and for designing artificial variants with altered properties and reactivities. 相似文献
19.
Wangdong Zeng Dr. Masatoshi Ishida Sangsu Lee Young Mo Sung Dr. Zebing Zeng Yong Ni Prof. Chunyan Chi Prof. Dongho Kim Prof. Jishan Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(49):16814-16824
A p‐quinodimethane (p‐QDM)‐bridged porphyrin dimer 1 has been prepared for the first time. An unexpected Michael addition reaction took place when we attempted to synthesize compound 1 by reaction of the cross‐conjugated keto‐linked porphyrin dimers 8 a and 8 b with alkynyl/aryl Grignard reagents. Alternatively, compound 1 could be successfully prepared by intramolecular Friedel–Crafts alkylation of the diol‐linked porphyrin dimer 14 with concomitant oxidation in air. Compound 1 shows intense one‐photon absorption (OPA, λmax=955 nm, ε=45400 M ?1 cm?1) and a large two‐photon absorption (TPA) cross‐section (σ(2)max=2080 GM at 1800 nm) in the near‐infrared (NIR) region due to its extended π‐conjugation and quinoidal character. It also exhibits a short singlet excited‐state lifetime of 25 ps. The cyclic voltammogram of 1 displays multiple redox waves with a small electrochemical energy gap of 0.86 eV. The ground‐state geometry, electronic structure, and optical properties of 1 have been further studied by density functional theory (DFT) calculations and compared with those of the keto‐linked dimer 8 b . This research has revealed that incorporation of a p‐QDM unit into the porphyrin framework had a significant impact on its optical and electronic properties, leading to a novel NIR OPA and TPA chromophore. 相似文献
20.
Karolina Hurej Wojciech Stawski Prof. Lechosław Latos‐Grażyński Dr. Miłosz Pawlicki 《化学:亚洲杂志》2016,11(23):3329-3333
A meso‐N‐pyrrole porphyrin converts into a π‐extended porphyrin forming an indolizine‐3‐one motif. The indolizine‐3‐one frame opens a lactam subunit preserving a six‐membered, heterocyclic structure fused with the main macrocycle. The optical properties of formed derivatives follow the structural modifications giving the absorbance and emission eventually modulated by the NH‐centered modifications of the fused unit. 相似文献