Search results
Search for "photostability" in Full Text gives 49 result(s) in Beilstein Journal of Organic Chemistry.
Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene
Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39
- photostability compared to ANTH and 9,10-ANTH derivatives, and a simple synthetic access makes it an attractive material as a deep-blue OLED emitter and an efficient fluorescent probe. Keywords: anthracene; dibromoanthracene; electron poor polyaromatic systems; fluorescence; perfluoroalkylation
- , bulky fluorinated substituents, such as perfluoroalkyls and perfluoroaryls, have been predicted by DFT [16] and shown experimentally [17], to improve the air- and photostability of acene-containing materials, by increasing their electron affinity and/or by sterically blocking reactive sites
- , respectively. In this work, we explored the effects of the bulky and electron-withdrawing substituent perfluorobenzyl (BnF) on the photophysical properties and on the air- and photostability of ANTH for the first time. We hypothesized that the steric bulk of BnF and the flexibility of the –CF2– moiety between
Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy
Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254
- photostability. From these results, it may be concluded that the sole addition of alkyne units to optimize MOST materials should be handled carefully because in some cases, like the one reported herein, it may result in an unfavorable tradeoff between the distinct MOST properties. After all, it still remains a
A facile three-component route to powerful 5-aryldeazaalloxazine photocatalysts
Beilstein J. Org. Chem. 2024, 20, 1831–1838, doi:10.3762/bjoc.20.161
- , value for Ar = Ph] [14][15][16][17][18] (Figure 1B). 5-Aryldeazaalloxazines 2 have been found to be even more powerful reductants than 1 due to their more negative ground-state reduction potential by ca. 300 mV. Moreover, 2 exhibits higher photostability than 1. Consequently, 5-aryldeazaalloxazine 2f
- methyl substituents were chosen to enhance the photophysical properties and photostability of the desired photocatalysts. It should be noted that our method encountered limitations when applying strongly deactivated anilines substituted with CF3 or acetyl groups, with no formation of 5
Supramolecular assemblies of amphiphilic donor–acceptor Stenhouse adducts as macroscopic soft scaffolds
Beilstein J. Org. Chem. 2024, 20, 1590–1603, doi:10.3762/bjoc.20.142
- reversibility and photostability in organic solvent (Figure S1a and S1b, Supporting Information File 1). The photoisomerization between O-DA11 and C-DA11, upon irradiation with 625 nm red light and thermal back reaction in the dark, could be repeated for over five cycles, with only 5% absorbance decreases per
- cycle (Figure S1a and S1b, Supporting Information File 1). In contrast, the previously studied reversibility of the photoswitching of DA10 had revealed 10% absorbance decreases per cycle [37], indicating a mild improvement to the fatigue resistance of DA11. To further investigate the photostability and
- stronger fatigue effect was observed in the photoisomerization of DA7 and DA6, this might be attributed to stabilization through hydrogen bonding and a favored cyclized-isomer in polar solvents. The increased alkyl linker length of DA10 and DA11 provided an improved photostability compared to DA7 and DA6
Mechanistic investigations of polyaza[7]helicene in photoredox and energy transfer catalysis
Beilstein J. Org. Chem. 2024, 20, 1236–1245, doi:10.3762/bjoc.20.106
- with a quantum yield of 0.34. The pronounced triplet formation was exploited for the isomerization reaction of (E)-stilbene to the Z-isomer and the cyclization of cinnamyl chloride. Catalyst degradation mainly occurs through the long-lived Aza-H triplet (28 µs), but the photostability is greatly
- studies on inherent photostability presented below). Our observations also revealed that while the styrene does not significantly quench the singlet state of Aza-H, it quenches the triplet state, suggesting that the formation of triplet-excited styrene via energy transfer is feasible (see Figure S7
- . Photostability measurements have also demonstrated that the inclusion of a triplet quencher like stilbene significantly enhances the longevity of the Aza-H chromophores, outperforming other well-known organic and metal-based photocatalysts such as 4CzIPN, riboflavin and [Ru(bpy)3](PF6)2 (Figure 5C and Supporting
Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments
Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30
- thermal- and photostability by the choice of oxygen as heteroatom, while keeping the possibility to trigger chalcogen extrusion via a radically different mechanistic route, as a result of the injection of electrons. Here, the presence of the imide functions appended to the naphthyl scaffold is crucial
Photochromic derivatives of indigo: historical overview of development, challenges and applications
Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23
- Despite thousands of years of use, the demand for indigo derivatives in the industry is still growing. The main reason for this is the unusual photostability and color fastness of indigo as industrial dye. This exceptional photostability of indigo and its derivatives has attracted significant scientific
- the O atom (Figure 6b). Moreover, the data of the first systematic computational ab initio study of the molecular mechanism of the photostability of indigo [36] support these findings and additionally point out that the single proton transfer (SPT) is more favorable than the double proton transfer
A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics
Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119
- ]. However, while progress has been made by increases in PCEs from ≈10% to ≈19% in the last decade, many of the materials used in OPVs suffer from low thermal and/or photostability, lengthy syntheses, high cost, and require harmful reagents for synthesis and processing. Therefore, it is necessary to design
Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis
Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30
- compounds [5]. The resulting supramolecular inclusion complexes provide enhanced water solubility and bioavailability/bioaccessibility of the nanoencapsulated bioactive compounds, higher oxidative and thermal stability or photostability of labile compounds, and their controlled release [6][7]. Vegetable oil
Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases
Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191
- more polar solvents (DMSO; 65–150 nm and MeOH; 65–130 nm) than in CHCl3 (59–85 nm). Compounds 3 presented good stability under white-LED irradiation conditions and moderate ROS generation properties were observed. Keywords: photophysical properties; photostability; quinoline; ROS generation; Schiff
- trifluoromethylated hybrid system comprising the Schiff base scaffolds from some 6-aminoquinolines and salicylaldehyde derivatives in order to analyze and evaluate their photophysical, photostability, and antioxidant properties for possible future applications in the pharmacological areas or materials sciences
- attributed to a greater electronic conjugation provided by the imine function present in the molecules of the series 3. Photostability and singlet oxygen quantum yield (ΦΔ) assays In order to be efficient for applications in photobiology, organic dyes must be stable when subjected to light irradiation for
Visible-light-mediated copper photocatalysis for organic syntheses
Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169
- ; however, they suffer from relatively poor photostability [14][15][16]. Transition-metal-photoredox catalysts, such as ruthenium and iridium polypyridyl complexes, exhibit high redox potentials, long excited state lifetimes, and strong absorption [17][18][19][20]. However, high cost and their scarcity
- the homoleptic and heteroleptic CuI complexes [22][31][36]. The introduction of bulky ligand substituents might efficiently prevent the reorganization of the excited state. Thus, changing the nature of the chelating ligand can improve the photostability and lifetime of the excited state to meet the
Recent advances in the application of isoindigo derivatives in materials chemistry
Beilstein J. Org. Chem. 2021, 17, 1533–1564, doi:10.3762/bjoc.17.111
- polymer with an effective ratio μh/μe = 3.94 cm2⋅V−1⋅s−1/3.50 cm2⋅V−1⋅s−1. Recently, diketopyrrolo[3,4-c]pyrrole (DPP) derivatives, which are highly conjugated electron-withdrawing heterocycles with high charge conductivity, broad absorption spectrum, photostability, and thermal stability have attracted
Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies
Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17
- spectroscopy, and isothermal titration calorimetry. Results and Discussion Characterization of the flavy building block In the first step the switchability and the photostability of pelargonidin chloride (Flavy) were investigated. The switching ability of Flavy is already well-known [79][80]. Here it was
Vicinal difluorination as a C=C surrogate: an analog of piperine with enhanced solubility, photostability, and acetylcholinesterase inhibitory activity
Beilstein J. Org. Chem. 2020, 16, 2663–2670, doi:10.3762/bjoc.16.216
- this might increase the accessibility of conformer 2f. We reasoned that comparing the biological activities of 1 vs 2 might shed light on this possibility (vide infra). Photostability A limitation of piperine (1) as a drug lead is its instability under UV light. The conjugated system of 1 is well-known
- physicochemical properties of compound 2 were found to be superior to piperine (1) itself in two key respects, namely photostability and aqueous solubility. The conformational analysis of 2 by DFT and NMR spectroscopy revealed that the lowest-energy conformations 2a–c are imperfect mimics of 1 but that a somewhat
- = hydroxybenzotriazole, DMF = N,N-dimethylformamide. Supporting Information Supporting Information File 402: Synthetic procedures, characterization data for novel compounds and copies of spectra; photostability assessment, conformational analysis of compound 2, and biological assays.
Heterogeneous photocatalysis in flow chemical reactors
Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125
- , wide electrochemical redox potentials, and photostability. However, these photocatalysts present serious drawbacks, such as toxicity, limited availability, and the overall cost of rare transition metal elements. This reduces their long-term viability, especially at an industrial scale. Heterogeneous
- separation and recycling, HPCats show advantages such as an enhanced photostability and selectivity [47][48]. A heterogeneous catalyst with a high surface area is often associated with a greater number of surface-active sites for catalysis to occur and makes morphological control critical to the catalyst
Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches
Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83
- superoxide radical anion by a reductive quenching and the rearrangement of the hydroperoxide intermediate [41]. The heterogeneous protocol using MOF porphyrins was significantly faster than the corresponding homogeneous photocatalysis, which was attributed to higher photostability of the porphyrins as MOF
- increase of singlet oxygen generation and photocatalytic activity under the sunlight irradiation. Furthermore, the steric hindrance around the porphyrin core, caused by the diacids, enhanced the catalyst photostability, allowing a lowers porphyrin load. The authors evaluated various protonated-TPPs, using
Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties
Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53
- optical features such as intense and narrow S0–S1 absorption and emission bands in the visible-to-near-infrared region, a high fluorescence quantum yield, and good photostability. For the applications mentioned above, various BODIPY dyes functionalized at the meso-, α-, and β-pyrrolic positions have been
Reversible photoswitching of the DNA-binding properties of styrylquinolizinium derivatives through photochromic [2 + 2] cycloaddition and cycloreversion
Beilstein J. Org. Chem. 2020, 16, 111–124, doi:10.3762/bjoc.16.13
- DNA only weakly by outside-edge association. Most notably, it was possible to switch between those two binding modes by irradiation with different excitation wavelengths (Scheme 3). Although the system still has to be improved with respect to photostability, it may be considered as a promising
Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization
Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263
- the biological efficiency of the photosensitizing agents [21][22]. At the same time fluorinated porphyrins are well known for their photostability and efficiency in generating long-lived triplet excited states through intersystem crossing (ISC) with minimal energy loss from excited states, and are
A photochemical determination of luminescence efficiency of upconverting nanoparticles
Beilstein J. Org. Chem. 2019, 15, 2671–2677, doi:10.3762/bjoc.15.260
- lanthanides used. The main application foreseen for these nanomaterials is as a substitute of quantum dots [3], since the combination of anti-Stokes emission and noncoherent absorption prevent any luminescence background. Their extreme photostability [4] make them also ideal candidates for single particle
Plasma membrane imaging with a fluorescent benzothiadiazole derivative
Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257
- -soluble and selective bioprobe for plasma membrane imaging. The new compound was efficiently synthesized in a two-step procedure with good yields. The photophysical properties were evaluated and the dye proved to have an excellent photostability in several solvents. DFT calculations were found in
- ETN vs Stokes shifts using the values provided by Richardt [44] were found in accordance with the ICT proposition and the calculated linear correlation from the plots [45] corroborated this proposition. The photostability of the new compound was measured in aqueous media as a preclude of the
- -soluble BTD fluorophore BTD-4APTEG was developed and applied as selective probe for bioimaging and stained plasma membranes selectively in the tested cells lines. The features envisaged for the synthesis of the structure proved to be capable of granting the dye water solubility, good photostability and
In search of visible-light photoresponsive peptide nucleic acids (PNAs) for reversible control of DNA hybridization
Beilstein J. Org. Chem. 2019, 15, 2500–2508, doi:10.3762/bjoc.15.243
- complementary DNA. For this purpose, we decided to measure thermal melting curves. Beforehand we verified the photostability of cis-PNA12(oF4Azo) (3) in the temperature ramp from 20 °C to 90 °C by UV–vis spectroscopy. We observed that the cis-isomer was always stable during the whole temperature range (Figure
Effect of ring size on photoisomerization properties of stiff stilbene macrocycles
Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233
- largest macrocycle (linked by a twelve carbon chain) is significantly higher than that of the stiff stilbene unit itself. In general, it is indicated that addition of even a flexible chain to the stiff stilbene unit may significantly affect its photochemical properties and increase the photostability of
- the resulting macrocycle. Keywords: DFT; molecular mechanics; photostability; photo-switch; ring-strain; stiff stilbene; Introduction The stiff stilbene (SS) molecule has drawn a lot of interest due to its photodynamic properties [1]. Stiff stilbenes typically undergo light triggered isomerization
Synthesis of a dihalogenated pyridinyl silicon rhodamine for mitochondrial imaging by a halogen dance rearrangement
Beilstein J. Org. Chem. 2019, 15, 2333–2343, doi:10.3762/bjoc.15.226
- Pearson coefficient ≥0.9 [46]. However, dye 15 has the benefit of further red-shifted absorption and emission properties as well as a photostability that allows for STED (stimulated emission depletion) nanoscopy [52][53]. As the 2-chloropyridinyl moiety in SiR dye 15 targets acidic cellular compartments
- stains mitochondria without background from unspecific membrane staining. However, higher photostability and a lower saturation intensity for STED result in a better performance in time-lapse live cell STED imaging of MitoESq-635. Taken together, our SiR dye 15 is a valid compromise between MitoESq-635
A golden opportunity: benzofuranone modifications of aurones and their influence on optical properties, toxicity, and potential as dyes
Beilstein J. Org. Chem. 2019, 15, 1781–1785, doi:10.3762/bjoc.15.171
- well as its longer term retention and photostability are required. Conclusion In conclusion, the benzofuranone portion of the aurone skeleton does have a definite impact on both the UV–vis spectral and cytotoxicity properties of aurones. Interestingly, the position of the substituent was often more
Other Beilstein-Institut Open Science Activities
