- Effects of bay substituents on the racemization barriers of perylene bisimides: Resolution of atropo-enantiomers
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The activation parameters for the interconversion of atropisomers (P- and M-enantiomer) of core-twisted perylene bisimides have been determined by dynamic NMR spectroscopy (DNMR) and time- and temperature-dependent CD spectroscopy. By comparing the activation parameters of a series of perylene bisimides containing halogen or aryloxy substituents in the bay area (1,6,7,12-positions), a clear structure-property relationship has been found that demonstrates that the kinetic and thermodynamic parameters for the inversion of enantiomers are dependent on the apparent overlap parameter Σr* of the bay substituents. This study reveals a high stability (ΔG ?368 K = 118 kJ/mol) for the atropo-enantiomers of tetrabromo-substituted perylene bisimide in solution. Accordingly, the enantiomers of this derivative could be resolved by HPLC on a chiral column. These enantiomers do not racemize in solution at room temperature and, thus, represent the first examples of enantiomerically pure core-twisted perylene bisimides.
- Osswald, Peter,Wuerthner, Frank
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- Highly fluorescent free-standing films assembled from perylenediimide microcrystals for boosting aniline sensing
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Molecular assembly has emerged as a key protocol for designing functional materials, although building in task-specific applications remains challenging. Here, a simple solvent-diffusion fabrication of highly fluorescent free-standing films (FFSFs) obtained from perylenediimide (PDI) microcrystals is described. The high fluorescence intensity of the resulting FFSFs follows from the mode of solid-state packing of the PDI molecules. The porous, crystalline FFSFs provide increased surface area and enable unobstructed diffusion of guest molecules for boosting aniline sensing with low detection limit, high selectivity and reversibility. Density functional theory (DFT) calculations indicate that the fluorescence quenching is caused by photoinduced electron transfer (PET). The new FFSFs furnish amplified discrimination of analytes and represent a major step ahead toward the rational synthesis of assembled sensing materials.
- Lü, Baozhong,Li, Pengyu,Li, Pengfei,Zhang, Yantu,Müllen, Klaus,Yin, Meizhen
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- Synthesis, characterization, photophysical properties and stability of bay-substituted tetrachloro-perylene diimide dianion salt by alkali treatment
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Bay-substituted tetrachloro-perylene diimide dianion salt was synthesized facilely by using K2CO3 as reducing agent. The structure was confirmed by using a very thorough analysis based on the data from 1H NMR, 13C NMR, FT-IR and UV–vis spectra. Perylene diimide dianion salt shows high stable characteristic in the air or in some specific solutions such as acidic solution or oxidizing metal ion dissolved in deionized water under solid condition. However, the dianion converts slowly into corresponding radical and neutral perylene diimide in alkali solutions. Furthermore, the perylene diimide dianion salt has high HOMO and LUMO energy levels in comparison with that of corresponding neutral perylene diimide derivatives.
- Li, Qizhe,Guo, Huiyun,Yang, Xu,Zhang, Shuo,Zhang, Haiquan
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- Modulating optical and electrochemical properties of perylene dyes by twisting aromatic π-system structures
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Three highly fluorescent perylene bisimide dyes were synthesized, where aromatic π-system structures are twisted to different degree by steric hindrance of two or four substitution groups at bay position. Light-emitting colours of these dye solutions can be modulated from green, yellow to red, and their fluorescence quantum yields increase up to approximate 100% with increasing the π-system twisting, which can be considered for new class of wavelength-tunable dye lasers. π-Twisted dyes are more sensitive to microenvironment changes. Thus, they are better fluorescence probe and sensory materials than planar dyes. Electrochemical cyclic voltammetry measurements revealed that these dyes are suitable for n-type optoelectrical devices and materials. These dye solids display near infra-red emission at 600–850 nm. Owing to strong π-π stacking interaction, planar dye solid loses its outstanding optical properties compared to its solution. In contrast, π-twisted dye solids retain their excellent optical properties including narrow emission bands and relatively high fluorescence quantum yields due to the suppression of π-π stacking interaction. Exceptional fluorescence polarization phenomena were observed for these π-twisted dye solids. These optical results revealed that π-twisted perylene bisimide dyes are more excellent optical materials than planar dyes.
- Wang, Ying,Zhang, Qi,Gong, Junbo,Zhang, Xin
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- Aggregation-induced red light emission material and preparation method thereof
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The invention discloses an aggregation-induced red light emission material and a preparation method thereof. The aggregation-induced red light emission material has a general structural formula shown as a formula [I]. When the aggregation-induced red ligh
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Paragraph 0067; 0068; 0098; 0099
(2017/08/28)
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- Aggregation-induced red light emission material and preparation method thereof
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The invention discloses an aggregation-induced red light emission material and a preparation method thereof. The aggregation-induced red light emission material has a structural formula represented by the formula [I]. The aggregation-induced red light emi
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Paragraph 0066; 0067
(2017/08/28)
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- Nondestructive photoluminescence read-out by intramolecular electron transfer in a perylene bisimide-diarylethene dyad
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A novel, highly stable photochromic dyad 3 based on a perylene bisimide (PBI) fluorophore and a diarylethene (DAE) photochrome was synthesized and the optical and photophysical properties of this dyad were studied in detail by steady-state and time-resolved ultrafast spectroscopy. This photochromic dyad can be switched reversibly by UV-light irradiation of its ring-open form 3 o leading to the ring-closed form 3 c, and back reaction of 3 c to 3 o by irradiation with visible light. Solvent-dependent fluorescence studies revealed that the emission of ring-closed form 3 c is drastically quenched in solvents of medium (e.g., chloroform) to high (e.g., acetone) polarities, while the emission of the ring-open form 3 o is appreciably quenched only in highly polar solvents like DMF. The strong fluorescence quenching of 3 c is attributed to a photoinduced electron-transfer (PET) process from the excited PBI unit to ring-closed DAE moiety, as this process is thermodynamically highly favorable with a Gibbs free energy value of -0.34 eV in dichloromethane. The electron-transfer mechanism for the fluorescence quenching of ring-closed 3 c is substantiated by ultrafast transient measurements in dichloromethane and acetone, revealing stabilization of charge-separated states of 3 c in these solvents. Our results reported here show that the new photochromic dyad 3 has potential for nondestructive read-out in write/read/erase fluorescent memory systems. Copyright
- Berberich, Martin,Natali, Mirco,Spenst, Peter,Chiorboli, Claudio,Scandola, Franco,Wuerthner, Frank
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supporting information
p. 13651 - 13664
(2013/01/15)
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- Method for producing organic field-effect transistors
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A method for producing an organic field-effect transistor, comprising the steps of: a) providing a substrate comprising a gate structure, a source electrode and a drain electrode located on the substrate, andb) applying an n-type organic semiconducting compound to the area of the substrate where the gate structure, the source electrode and the drain electrode are located, wherein the n-type organic semiconducting compound is selected from the group consisting of compounds of the formula I wherein R1, R2, R3and R4are independently hydrogen, chlorine or bromine, with the proviso that at least one of these radicals is not hydrogen,Y1 is O or NRa, wherein Ra is hydrogen or an organyl residue,Y2 is O or NRb, wherein Rb is hydrogen or an organyl residue,Z1, Z2, Z3 and Z4 are O, where, in the case that Y1 is NRa, one of the residues Z1 and Z2 may be a NRc group, where Ra and Rc together are a bridging group having 2 to 5 atoms between the terminal bonds, where, in the case that Y2 is NRb, one of the residues Z3 and Z4 may be a NRd group, where Rb and Rd together are a bridging group having 2 to 5 atoms between the terminal bonds.
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Page/Page column 33-34
(2011/04/18)
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- Synthesis and characterization of 1,7-disubstituted and 1,6,7,12-tetrasubstituted perylenetetracarboxy-3,4:9,10-diimide derivatives
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A variety of perylenetetracarboxy-3,4:9,10-diimide derivatives have been synthesized. Particular attention was paid to substituents in positions 1, 6, 7 or 12. The energy differences between the frontier orbitals have been determined using optical spectroscopy (UV and fluorescence). The energy of the lowest unoccupied orbitals (LUMOs) were obtained by cyclic voltammetry. From both studies, the energies of the highest occupied orbitals (HOMOs) were also been calculated. A Hammett-type relationship was observed for the reduction potentials (Ered11/2) when correlated with the σ-ortho parameter. The energies of the frontier orbitals define the domains of application of these compounds. They significantly depend on the substitution in positions 1, 6, 7, or 12.
- Queste, Mathieu,Cadiou, Cyril,Pagoaga, Bernard,Giraudet, Louis,Hoffmann, Norbert
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p. 2537 - 2545
(2011/01/12)
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- The synthesis and characterisation of a free-base porphyrin-perylene dyad that exhibits electronic coupling in both the ground and excited states
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A covalent dyad composed of a free-base porphyrin and a perylene diimide (1) was synthesised and characterised by NMR, HRMS, UV/Vis and fluorometric methods. UV/Vis spectrophotometric analysis indicated a moderate coupling between the components in the gr
- Mathew, Simon,Johnston, Martin R.
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experimental part
p. 248 - 253
(2009/06/18)
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- Cyclodehydrogenation of poly(perylene) to poly(quaterrylene): Toward poly(peri-naphthalene)
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Cyclodehydrogenation of soluble polyperylenes gives polymers containing predominantly quaterrylene units by spectral analysis. Evidence for larger rylene units is also seen. These polymers represent important intermediates toward a poly(peri-naphthalene) (PPN). Reactions on model compounds suggest that the insolubility of polymers with larger rylene units is predominantly due to the rigidity of the polymer backbone.
- Former, Carsten,Becker, Stefan,Grimsdale, Andrew C.,Muellen, Klaus
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p. 1576 - 1582
(2007/10/03)
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