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Search for "photophysical properties" in Full Text gives 204 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Self-assembly behaviors of perylene- and naphthalene-crown macrocycle conjugates in aqueous medium
Beilstein J. Org. Chem. 2019, 15, 1203–1209, doi:10.3762/bjoc.15.117
- properties, such as charge transport and photophysical properties [69][70][71][72][73][74]. While the morphologies of these aggregates were greatly influenced by solvents, molecular structures and shapes, as well as the fraction of hydrophilic and/or hydrophobic parts [75][76][77][78][79][80][81]. By far
Precious metal-free molecular machines for solar thermal energy storage
Beilstein J. Org. Chem. 2019, 15, 1096–1106, doi:10.3762/bjoc.15.106
- photoisomerization and a longer life time of the higher energy forms in comparison with the known analogs. The chemical structures of all dyes in the series were characterized by NMR, UV–vis, IR spectroscopy and elemental analysis. The steady-state photophysical properties of the dyes were elucidated. The stability
- . First of all, the azacrown nitrogen atom is linked directly to the dye and it is part of the chromophore system, responsible for the “push–pull” effect and the photophysical properties of the dye. This provides control over the “push–pull” effect in the chromophore by switching on and off states (i.e
- were proved by NMR spectroscopy, elemental analysis, IR and UV–vis spectroscopy. Photophysical properties Steady-state absorption and emission spectroscopy Next we elucidated the photophysical properties of the chosen compounds and determined their suitability to be used as MOST systems. First, we
Synthesis of functionalized diazocines for application as building blocks in photo- and mechanoresponsive materials
Beilstein J. Org. Chem. 2019, 15, 727–732, doi:10.3762/bjoc.15.68
- to 3,3’- and 4,4’-diaminodiazocine, which have been implemented in macromolecules for conformation switching, our compounds exhibit improved photophysical properties (photostationary states, separation of absorption bands in the cis and trans configuration). Hence they are promising candidates as
- the amino-functionalized diazocines 6a and 6b [34]. Additionally, the diazocine 4b was converted into the divinyldiazocine 7. Towards this end, the hydroxy groups were tosylated, followed by elimination with potassium butoxide [35][36]. The photochemical and photophysical properties of compounds 4–7
- azo condensation proved to be reliable key steps in the synthesis of these substituted diazocines. The photophysical properties of compounds 4–7 were investigated by NMR and UV–vis experiments. The previously investigated 3,3’-diaminodiazocine 2 and 4,4’-diaminodiazocine 3 exhibited poor
Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines
Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41
- ; Introduction Purine [1][2][3][4][5][6][7] and 7-deazapurine (IUPAC name: pyrrolo[2,3-d]pyrimidine) [8][9][10][11] derivatives have been progressively studied for decades due to their wide range of biological activities and photophysical properties. Currently, the synthesis of push–pull systems is a promising
- -deazapurines (Figure 1 compounds of type G and H) in order to determine and to compare their fluorescent properties. The synthetic approach towards 7-deazapurine derivatives H has been recently disclosed by us [39], but the photophysical properties of these compounds have not been studied thus far. In this
- series possessing identical substitution pattern (structural congeners G and H, Figure 1). The easy access to the title compounds opened a possibility for a comparative study of their photophysical properties. Synthesis N(9)-Alkylated-2,6-diazidopurine 2a was synthesized in two steps from commercially
Application of olefin metathesis in the synthesis of functionalized polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials
Beilstein J. Org. Chem. 2019, 15, 310–332, doi:10.3762/bjoc.15.28
- isolated yields exceeding 60%. Chromophore-functionalized silsesquioxane-core dendrimers were obtained to investigate their photophysical properties [12][14]. In the synthesized compounds chromophore properties were only slightly influenced by the core. The possibility of fine-tuning of the photophysical
- strongly affect photophysical properties [26]. In the subsequent paper the authors describe the use of OVS or mixtures of T10 and T12 units in the synthesis of hydroxyphenyl-terminated silsesquioxanes. Such derivatives were obtained via cross metathesis with 4-acetoxystyrene or via a sequence of cross
- properties of the POSS-based dendritic molecule not only by changing the chromophore but also by providing tailored steric interactions between bridges and/or chromophores was proved [14]. Interestingly, the 4’-vinylbiphenyl-3,5-dicarbaldehyde group modified macromolecule (Figure 5d) displayed the ability to
N-Arylphenothiazines as strong donors for photoredox catalysis – pushing the frontiers of nucleophilic addition of alcohols to alkenes
Beilstein J. Org. Chem. 2019, 15, 52–59, doi:10.3762/bjoc.15.5
- photoredox concept is based on the photophysical properties of the excited photoredox catalyst, the idea of the conPET concept mimics nature’s light collection system and consecutively collects the energy of two photons stored in the excited state of the initially pre-promoted photoredox catalyst’s radical
Synthesis of mono-functionalized S-diazocines via intramolecular Baeyer–Mills reactions
Beilstein J. Org. Chem. 2018, 14, 2799–2804, doi:10.3762/bjoc.14.257
- difficult to achieve. On this account, bridged azobenzenes (diazocines), would be more suitable as photoswitches in pharmacologically active compounds [8]. Besides their superior photophysical properties, diazocines are more stable in the cis configuration and could therefore be administered in their
Photocatalyic Appel reaction enabled by copper-based complexes in continuous flow
Beilstein J. Org. Chem. 2018, 14, 2730–2736, doi:10.3762/bjoc.14.251
- conversion of an alcohol to bromide involved screening a wide variety of structurally varied complexes. Our group has previously demonstrated that the nature of each ligand influences the physical and photophysical properties as well as catalytic activity of the resulting catalyst (Figure 2) [27]. A library
Transition metal-free oxidative and deoxygenative C–H/C–Li cross-couplings of 2H-imidazole 1-oxides with carboranyl lithium as an efficient synthetic approach to azaheterocyclic carboranes
Beilstein J. Org. Chem. 2018, 14, 2618–2626, doi:10.3762/bjoc.14.240
- ][19][20][21], as well as unique photophysical properties [22][23][24][25][26]. Thus, the development of effective approaches to azaheterocyclic carboranes is currently considered to be one of the most important synthetic challenges. At present, there are three main synthetic strategies in the design
Applications of organocatalysed visible-light photoredox reactions for medicinal chemistry
Beilstein J. Org. Chem. 2018, 14, 2035–2064, doi:10.3762/bjoc.14.179
- some basic data of these photocatalysts are presented, to serve as an easy reference to the reader, with respect to their structure, electrochemical and photophysical properties. Figure 3 shows the structures of the various compounds that are used on multiple occasions as photocatalysts in the
A self-assembled photoresponsive gel consisting of chiral nanofibers
Beilstein J. Org. Chem. 2018, 14, 1994–2001, doi:10.3762/bjoc.14.174
- formation of supramolecular structure. To investigate the potential photoresponsiveness of compound 3, the UV–vis absorption spectrum was measured to trace photochemical and photophysical properties of the solution of compound 3 (1.0 × 10−5 M in chloroform). As shown in Figure 2, the azobenzene trans-isomer
Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril
Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171
- host-induced protonation and thus to a fluorescence increase. The possibility to tune binding affinities and pKa values is demonstrated and it is shown that, in combination with the beneficial photophysical properties of BODIPYs, several new applications of host–dye reporter pairs can be implemented
- . Synthesis of BODIPY derivatives. Photophysical properties of the synthesized BODIPY derivatives.a Properties of the CB7–BODIPY host–guest complexes.a Supporting Information Supporting Information File 472: Experimental details and supporting figures. Acknowledgements Financial support from the DFG (HE
Synthesis and characterization of π–extended “earring” subporphyrins
Beilstein J. Org. Chem. 2018, 14, 1956–1960, doi:10.3762/bjoc.14.170
- further red-shifted and more intense. This work extends the research of “earring” porphyrins to “earring” subporphyrins. Investigations on their photophysical properties and further functionalization are underway. Partial 1H NMR spectrum of 3. X-ray crystal structures of 3: a) top view; b) side view
Synthesis of 9-arylalkynyl- and 9-aryl-substituted benzo[b]quinolizinium derivatives by Palladium-mediated cross-coupling reactions
Beilstein J. Org. Chem. 2018, 14, 1871–1884, doi:10.3762/bjoc.14.161
- protocol for Pd-mediated reactions may be employed for other base-sensitive substrates as well. The photophysical properties as well as the DNA-binding properties of the (arylethynyl)benzo[b]quinolizinium derivatives were studied. It was demonstrated that derivatives 2a–d bind to duplex and quadruplex DNA
Synthesis and photophysical studies of a multivalent photoreactive RuII-calix[4]arene complex bearing RGD-containing cyclopentapeptides
Beilstein J. Org. Chem. 2018, 14, 1758–1768, doi:10.3762/bjoc.14.150
- internal cell environment or exert a photocytotoxic activity. The use of lipophilic ligands allows the corresponding ruthenium complexes to passively diffuse inside cells but limits their structural and photophysical properties. Moreover, this strategy does not provide any cell selectivity. This limitation
- platform. The photophysical properties of this RuII–calixarene conjugate were thus examined and compared to those of the reference complex [Ru(TAP)2phen]2+. Results and Discussion Synthesis of RuII-calixarene conjugate 9 For the synthesis of the target multivalent system, the strategy relies on the
- integrins. However, the possible H-bonding interactions between neighboring RGD units could be a drawback in view of the accessibility of the arginine groups to interact with the integrins. Photophysical properties of RuII-calixarene conjugate 9 The absorption and emission spectra of Ru-calix(RGD)4
Metal-free formal synthesis of phenoxazine
Beilstein J. Org. Chem. 2018, 14, 1491–1497, doi:10.3762/bjoc.14.126
- fused between two benzene rings. A range of compounds with interesting biological or photophysical properties contain the phenoxazine core, where the amine moiety is either functionalized or oxidized to the corresponding imine [1][2][3][4]. Phenoxazine derivatives can display antitumor activity [5][6][7
Recent advances in phosphorescent platinum complexes for organic light-emitting diodes
Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124
- , photophysical properties and OLED performances, Chi, Kim and co-workers analyzed the X-ray structures of Pt(fppz)2 (13) and other related platinum(II) complexes 14 and 15 in both single crystal and thin film samples (Figure 7) [13]. They observed different degrees of crystallinity as a function of the
- worth to note that this excimeric emission was reduced on increasing the generation of the ancillary ligand, highlighting the importance of this molecular design strategy towards highly efficient dopants. The interesting photophysical properties of these compounds prompted the evaluation of their
- the dopant was also shown by Strassner and co-workers [36][37][38]. Compared with previously reported imidazolylidene and triazolylidene acetylacetonate (acac) platinum(II) complexes, complexes 12 bearing 1,3-thiazol-2-ylidene carbenes outperformed the former when evaluating the photophysical
Two novel blue phosphorescent host materials containing phenothiazine-5,5-dioxide structure derivatives
Beilstein J. Org. Chem. 2018, 14, 869–874, doi:10.3762/bjoc.14.73
- time, the photophysical properties, electrochemical properties and their thermal stability were studied and the expected results were obtained. Results and Discussion Synthesis and theoretical calculations The synthesis route for CEPDO and CBPDO is shown in Scheme 1. The detailed synthesis procedures
- electron-withdrawing ability of the phenothiazine-5,5-dioxide unit, thus realized the orbital separation of hole and electron transport in the same molecule. This indicated CEPDO and CBPDO have bipolar characteristic. Photophysical properties Figure 2 presents the UV–vis absorption, photoluminescence and
D–A–D-type orange-light emitting thermally activated delayed fluorescence (TADF) materials based on a fluorenone unit: simulation, photoluminescence and electroluminescence studies
Beilstein J. Org. Chem. 2018, 14, 672–681, doi:10.3762/bjoc.14.55
- vibronic structure [7]. The ΔEST of 1 and 2 are 0.19 and 0.09 eV, respectively, indicating that compound 2 may have a much more efficient RISC process than 2 [19][20] (Table 3). To gain a further understanding of the photophysical properties of 1 and 2 in solid state, two doped films in 4,4’-dicarbazolyl
- ability to reduce the efficiency roll-off, which comes to the same conclusion with the analysis of their photophysical properties. Conclusion In summary, two novel D–A–D-type orange-emitting TADF materials, namely 2,7-bis(9,9-dimethylacridin-10(9H)-yl)-9H-fluoren-9-one (27DACRFT, 1) and 3,6-bis(9,9
- DFT and TD-DFT. Photophysical properties of the investigated molecules 1 and 2. Photophysical properties of the 1 and 2 doped in CBP films (8 wt %) at room temperature. Summary of the device performances of the OLEDs based on 1 and 2. Supporting Information Supporting Information File 8: Experimental
Enhanced quantum yields by sterically demanding aryl-substituted β-diketonate ancillary ligands
Beilstein J. Org. Chem. 2018, 14, 664–671, doi:10.3762/bjoc.14.54
- ][39][40][41]. We herein present the synthesis and photophysical properties of two new C^C* cyclometalated platinum complexes. Both are based on the original 3-methyl-1-phenylimidazolium (MPIM) ligand system which together with the acac auxiliary ligand showed only a very low quantum yield of 7%. We
Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)
Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18
- noticed that the photophysical properties and the geometry of molecules that are suspected to be TADF emitters are often investigated by theoretical calculations prior to synthesis, optimizing the chance to get suitable energy levels and the desired ΔEST. This strategy was notably applied to the design of
- , an analogue of T9, i.e., T12, differing by the removal of a phenyl ring between the carbazole and the triazine units proved once again the crucial role of the oscillator strength in the photophysical properties [51]. Notably, major differences in the separation of their HOMO and LUMO energy levels
- substitution pattern of the carbazole unit on the photophysical properties. While maintaining the same number of carbazole units on the emitter and by varying the substitution pattern of the carbazole core, only a weak influence on the EL characteristics was evidenced [55]. In fact, performances only varied by
Synthesis and spectroscopic properties of β-meso directly linked porphyrin–corrole hybrid compounds
Beilstein J. Org. Chem. 2018, 14, 187–193, doi:10.3762/bjoc.14.13
- condensation reaction of meso-substituted dipyrromethanes with β-formylated meso-tetraphenylporphyrins. Spectroscopic and photophysical properties of the new hybrid structures have been determined. Higher quantum yields of some of the synthesized hybrid compounds indicate that these compounds can be considered
- –corrole hybrid derivatives. *100 mol % of AlCl3 was used as a catalyst. Optimization of the reaction conditions. Photophysical properties of hybrid compounds. Supporting Information Supporting Information File 34: General experimental information, experimental details on the synthesis of products 4 and
Fluorescent nucleobase analogues for base–base FRET in nucleic acids: synthesis, photophysics and applications
Beilstein J. Org. Chem. 2018, 14, 114–129, doi:10.3762/bjoc.14.7
- dealing with the synthesis of the key players of base–base FRET, i.e., the base analogue donor and acceptor molecules, the second one dealing with their photophysical properties and the third one dealing with their application in studying nucleic acid-containing systems. Synthesis of fluorescent base
- protection groups is paramount as an extensive use adds additional steps as well as complexity to the synthesis. The design and synthesis of fluorescent nucleobase analogues (FBAs) add on additional challenges such as obtaining features that introduce useful photophysical properties, for example, extended
- , the oxo-analogue tCO, which Lin et al. initially prepared in 1995 [41], was re-synthesized in order to characterize its photophysical properties, using the same procedure except that p-toluoyl protecting groups rather than acetyl were used [31]. In 2009, we published the first base–base FRET system
Halogen-containing thiazole orange analogues – new fluorogenic DNA stains
Beilstein J. Org. Chem. 2017, 13, 2902–2914, doi:10.3762/bjoc.13.283
- atoms (connected directly to the chromophore or as side groups) on the molar absorptivity and the fluorescence intensity of a series of new TO analogues. Photophysical properties of a series of TO analogues that have fluoro- or trifluoromethyl groups connected to the heterocyclic end groups of the
- chromophores have been studied by Armitage and co-workers [42][43]. According to these studies the fluorination of the symmetrical [42] and unsymmetrical [43] cyanine dyes results in reduced aggregation and significantly improved the photostability and photophysical properties of the dyes. The authors [43
- for the success of the reaction because of the CH-acidity of the benzyl fragment, which otherwise leads to the possibility of side reactions if trimethylamine or other less hindered basic reagents are employed. Photophysical properties Absorption The longest wavelength absorption maxima of the studied
Pyrene–nucleobase conjugates: synthesis, oligonucleotide binding and confocal bioimaging studies
Beilstein J. Org. Chem. 2017, 13, 2521–2534, doi:10.3762/bjoc.13.249
- at ambient temperature. The absorption and emission spectra of the adenine derivatives 3 and 5 are reproduced in Figure 4. The photophysical properties of 5 (Figure 4a) resemble the properties of unsubstituted pyrene [30]. In the low energy UV and blue spectral region between 250 and 400 nm, three
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