scholarly journals Iron-Catalyzed Synthesis, Structure, and Photophysical Properties of Tetraarylnaphthidines

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1608 ◽  
Author(s):  
Alexander Purtsas ◽  
Sergej Stipurin ◽  
Olga Kataeva ◽  
Hans-Joachim Knölker
Keyword(s):  
Photophysical Properties ◽  
Coupling Reaction ◽  
Quantum Yields ◽  
Synthetic Approach ◽  
Iron Phthalocyanine ◽  
Phthalocyanine Complex

We describe the synthesis and photophysical properties of tetraarylnaphthidines. Our synthetic approach is based on an iron-catalyzed oxidative C–C coupling reaction as the key step using a hexadecafluorinated iron–phthalocyanine complex as a catalyst and air as the sole oxidant. The N,N,N’,N’-tetraarylnaphthidines proved to be highly fluorescent with quantum yields of up to 68%.

Regioselective Oxidative Cross-Coupling Reaction: Synthesis of Imidazo[1,2-a]pyridine Fluorophores

Synthesis ◽  
2021 ◽  
Author(s):  
Xianglong Chu ◽  
Yadi Niu ◽  
Chen Ma ◽  
Xiaodong Wang ◽  
Yunliang Lin ◽  
...  
Keyword(s):  
Photophysical Properties ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Quantum Yields ◽  
Fluorescence Quantum Yields ◽  
Cross Coupling Reaction ◽  
Color Tunable ◽  
Palladium Catalyzed ◽  
Structure Relationship ◽  
High Fluorescence

AbstractA rapid access to a series of N-heteroarene fluorophores has been developed on the basis of the palladium-catalyzed direct oxidative C–H/C–H coupling of imidazo[1,2-a]pyridines with thiophenes/furans. The photophysical properties–structure relationship was systematically investigated. The resulting N-heteroarene fluorophores present color-tunable emissions (λem: 431–507 nm in CH2Cl2) and high fluorescence quantum yields (up to 91% in CH2Cl2).

Extending the Conjugation of Pechmann Lactone Thienyl Derivatives: A New Class of Small Molecules for Organic Electronics Application

Synthesis ◽  
2017 ◽  
Vol 50 (06) ◽  
pp. 1284-1292 ◽  
Author(s):  
Massimo Calamante ◽  
Gianna Reginato ◽  
Alessio Dessì ◽  
Matteo Bartolini ◽  
Lorenzo Zani ◽  
...  
Keyword(s):  
Small Molecules ◽  
Organic Electronics ◽  
Fluorescent Dyes ◽  
Photophysical Properties ◽  
Emission Spectra ◽  
Coupling Reaction ◽  
Spectroscopic Characterization ◽  
Synthetic Approach ◽  
New Class ◽  
Near Ir

The preparation and spectroscopic characterization of some symmetrical small molecules containing the disubstituted (E)-3,3′-bifuranylidene-2,2′-dione chromophore (the so-called Pechmann lactone) and featuring an extended conjugation are reported. The synthetic approach of such compounds is based on the Stille–Migita coupling reaction, which is carried out in very mild conditions, suitable to be applied with the very sensitive Pechmann core. The absorption and emission spectra of the new molecules obtained have been recorded in solution and clearly show how their photophysical properties can be modulated by a proper choice of the (hetero)aromatic terminal groups. The compounds prepared in this study (or close analogues thereof) have interesting optical properties and could find application as semiconductors in organic electronics or as near-IR fluorescent dyes.

scholarly journals The Photostability of Novel Boron Hydride Blue Emitters in Solution and Polystyrene Matrix

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 589
Author(s):  
Jakub Ševčík ◽  
Pavel Urbánek ◽  
Barbora Hanulíková ◽  
Tereza Čapková ◽  
Michal Urbánek ◽  
...  
Keyword(s):  
Thin Films ◽  
Photophysical Properties ◽  
Inorganic Compounds ◽  
Solid Polymer ◽  
Organic Polymer ◽  
Quantum Yields ◽  
Boron Hydride ◽  
Polystyrene Matrix ◽  
Blue Emitters ◽  
Solvent Blends

In recent work, the boron hydride anti-B18H22 was announced in the literature as a new laser dye, and, along with several of its derivatives, its solutions are capable of delivering blue luminescence with quantum yields of unity. However, as a dopant in solid polymer films, its luminescent efficiencies reduce dramatically. Clarification of underlying detrimental effects is crucial for any application and, thus, this contribution makes the initial steps in the use of these inorganic compounds in electrooptical devices based on organic polymer thin films. The photoluminescence behavior of the highly luminescent boron hydrides, anti-B18H22 and 3,3′,4,4′-Et4-anti-B18H18, were therefore investigated. The quantum yields of luminescence and photostabilities of both compounds were studied in different solvents and as polymer-solvent blends. The photophysical properties of both boranes are evaluated and discussed in terms of their solvent-solute interactions using photoluminescence (PL) and NMR spectroscopies. The UV degradability of prepared thin films was studied by fluorimetric measurement. The effect of the surrounding atmosphere, dopant concentration and the molecular structure were assessed.

scholarly journals Photochemical Reactivity of Naphthol-Naphthalimide Conjugates and Their Biological Activity

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3355
Author(s):  
Matija Sambol ◽  
Patricia Benčić ◽  
Antonija Erben ◽  
Marija Matković ◽  
Branka Mihaljević ◽  
...  
Keyword(s):  
Biological Activity ◽  
Rational Design ◽  
Human Cancer ◽  
Photophysical Properties ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Quinone Methide ◽  
Quantum Yields ◽  
Photochemical Reactivity ◽  
Human Cancer Cell Lines

Quinone methide precursors 1a–e, with different alkyl linkers between the naphthol and the naphthalimide chromophore, were synthesized. Their photophysical properties and photochemical reactivity were investigated and connected with biological activity. Upon excitation of the naphthol, Förster resonance energy transfer (FRET) to the naphthalimide takes place and the quantum yields of fluorescence are low (ΦF ≈ 10−2). Due to FRET, photodehydration of naphthols to QMs takes place inefficiently (ΦR ≈ 10−5). However, the formation of QMs can also be initiated upon excitation of naphthalimide, the lower energy chromophore, in a process that involves photoinduced electron transfer (PET) from the naphthol to the naphthalimide. Fluorescence titrations revealed that 1a and 1e form complexes with ct-DNA with moderate association constants Ka ≈ 105–106 M−1, as well as with bovine serum albumin (BSA) Ka ≈ 105 M−1 (1:1 complex). The irradiation of the complex 1e@BSA resulted in the alkylation of the protein, probably via QM. The antiproliferative activity of 1a–e against two human cancer cell lines (H460 and MCF 7) was investigated with the cells kept in the dark or irradiated at 350 nm, whereupon cytotoxicity increased, particularly for 1e (>100 times). Although the enhancement of this activity upon UV irradiation has no imminent therapeutic application, the results presented have importance in the rational design of new generations of anticancer phototherapeutics that absorb visible light.

scholarly journals Indenopyrans – synthesis and photoluminescence properties

2016 ◽  
Vol 12 ◽  
pp. 825-834 ◽  
Author(s):  
Andreea Petronela Diac ◽  
Ana-Maria Ţepeş ◽  
Albert Soran ◽  
Ion Grosu ◽  
Anamaria Terec ◽  
...  
Keyword(s):  
Solid State ◽  
Emission Band ◽  
Fluorescence Spectra ◽  
Photophysical Properties ◽  
Quantum Yields ◽  
Band Broadening ◽  
Photoluminescence Properties ◽  
Fluorescence Quantum Yields ◽  
Blue Emitters ◽  
Solid State Fluorescence

New indeno[1,2-c]pyran-3-ones bearing different substituents at the pyran moiety were synthesized and their photophysical properties were investigated. In solution all compounds were found to be blue emitters and the trans isomers exhibited significantly higher fluorescence quantum yields (relative to 9,10-diphenylanthracene) as compared to the corresponding cis isomers. The solid-state fluorescence spectra revealed an important red shift of λmax due to intermolecular interactions in the lattice, along with an emission-band broadening, as compared to the solution fluorescence spectra.

scholarly journals Synthesis, Characterization and Photophysical Properties of a New 2,5-Di(aryl)phosphole Derivative and Their Trigonal Copper-Phosphole Complexes

2020 ◽  
Author(s):  
Neskarlys Rios ◽  
Franmerly Fuentes ◽  
Juan Manuel Garcia Garfido ◽  
Yomaira Otero
Keyword(s):  
Field Strength ◽  
Fluorescence Spectroscopy ◽  
Photophysical Properties ◽  
High Yield ◽  
Quantum Yields ◽  
Ligand Field ◽  
Emission Energy ◽  
Esi Ms

<div>A new phosphole derivative 2,5-di(2-quinolyl)-1-phenylphosphole (<b>1</b>) was synthesized by using the Fagan-Nugent method. Phosphole was obtained as an air stable solid in high yield (73%). Additionally, two new copper phosphole complexes [CuX(Phosphole)<sub>2</sub>] (X = Cl (<b>2a</b>), I (<b>2b</b>), Phosphole = <b>1</b>) have been synthesized by reaction of CuX (X = Cl, I) and phosphole derivative (<b>1</b>). All compound were characterized by NMR, ESI-MS, UV–Vis and fluorescence spectroscopy. The photophysical properties of all compounds were analyzed, UV-Vis spectra of the complexes <b>2a-b</b> shown π–π* transitions with shift very similar to the found in the free phosphole due to that their symmetrical structures inhibits efficient ILCT. We have found that the compounds <b>1</b>, <b>2a-b</b> exhibited fluorescence between 460 and 583 nm with quantum yields of Φ<sub>f</sub> = 0.04 – 0.11. The emission energy of <b>2b</b> is higher than <b>2a</b>, suggesting that λ<sub>max</sub> is affected by the ligand-field strength of the halogen ions in the complexes (I<sup>-</sup> < Cl<sup>-</sup> ).</div>

scholarly journals Synthesis, Characterization and Photophysical Properties of a New 2,5-Di(aryl)phosphole Derivative and Their Trigonal Copper-Phosphole Complexes

2020 ◽  
Author(s):  
Neskarlys Rios ◽  
Franmerly Fuentes ◽  
Juan Manuel Garcia Garfido ◽  
Yomaira Otero
Keyword(s):  
Field Strength ◽  
Fluorescence Spectroscopy ◽  
Photophysical Properties ◽  
High Yield ◽  
Quantum Yields ◽  
Ligand Field ◽  
Emission Energy ◽  
Esi Ms

<div>A new phosphole derivative 2,5-di(2-quinolyl)-1-phenylphosphole (<b>1</b>) was synthesized by using the Fagan-Nugent method. Phosphole was obtained as an air stable solid in high yield (73%). Additionally, two new copper phosphole complexes [CuX(Phosphole)<sub>2</sub>] (X = Cl (<b>2a</b>), I (<b>2b</b>), Phosphole = <b>1</b>) have been synthesized by reaction of CuX (X = Cl, I) and phosphole derivative (<b>1</b>). All compound were characterized by NMR, ESI-MS, UV–Vis and fluorescence spectroscopy. The photophysical properties of all compounds were analyzed, UV-Vis spectra of the complexes <b>2a-b</b> shown π–π* transitions with shift very similar to the found in the free phosphole due to that their symmetrical structures inhibits efficient ILCT. We have found that the compounds <b>1</b>, <b>2a-b</b> exhibited fluorescence between 460 and 583 nm with quantum yields of Φ<sub>f</sub> = 0.04 – 0.11. The emission energy of <b>2b</b> is higher than <b>2a</b>, suggesting that λ<sub>max</sub> is affected by the ligand-field strength of the halogen ions in the complexes (I<sup>-</sup> < Cl<sup>-</sup> ).</div>

scholarly journals The Temperature Dependence of Fundamental Photophysical Properties of [Eu(MeOH-d4)9]3+ Solvates and [Eu.DOTA(MeOH-d4)]- Complexes

2021 ◽  
Author(s):  
Nicolaj Kofod ◽  
Lea Gundorff Nielsen ◽  
Thomas Just Sørensen
Keyword(s):  
Transition Probabilities ◽  
Photophysical Properties ◽  
Transition Probability ◽  
Energy Levels ◽  
Emission Spectra ◽  
Lanthanide Ions ◽  
Quantum Yields ◽  
Luminescence Spectra ◽  
Absorption Cross ◽  
Apparent Lack

The trivalent lanthanide ions show optical transitions between energy levels within the 4f shell. All these transitions are formally forbidden according to the quantum mechanical selection rules used in molecular photophysics. Nevertheless, highly luminescent complexes can be achieved, and terbium(iii) and europium(iii) ions are particularly efficient emitters. This report started when an apparent lack of data in the literature led us to revisit the fundamental photophysics of europium(iii). The photophysical properties of two complexes – [Eu.DOTA(MeOH-d4)]- and [Eu(MeOH-d4)9]3+ – were investigated in deuterated methanol at five different temperatures. Absorption spectra showed decreased absorption cross sections as the temperature was increased. Luminescence spectra and time-resolved emission decay profiles showed a decrease in intensity and lifetime as a temperature was increased. Having corrected the emission spectra for the actual number of absorbed photons and differences in non-radiative pathways, the relative emission probability was revealed. These were found to increase with increasing temperature. The transition probability for luminescence was shown to increase with temperature, while the transition probability for light absorption decreased. The changes in transition probabilities were correlated to a change in the symmetry of the absorber or emitter, with an average increase in symmetry lowering absorption cross section and access to more asymmetric structures increasing the emission rate constant. Determining luminescence quantum yields and the Einstein coefficient for spontaneous emission allowed us to conclude that lowering symmetry increases both. Further, it was found that collisional self-quenching is an issue for lanthanide luminescence, when high concentrations are used. Finally, detailed analysis revealed results that show the so-called ‘Werts’ method’ for calculating radiative lifetimes and intrinsic quantum yields are based on assumption that does not hold for the two systems investigated here. We conclude that we are lacking a good theoretical description of the intraconfigurational f-f transition, and that there are still aspects of fundamental lanthanide photophysics to be explored.<br>

scholarly journals Organic Nanoparticles Based on D-A-D Small Molecule: Self-Assembly, Photophysical Properties, and Synergistic Photodynamic/Photothermal Effects

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 502
Author(s):  
Liangliang Yue ◽  
Haolan Li ◽  
Qi Sun ◽  
Xiaogang Luo ◽  
Fengshou Wu ◽  
...  
Keyword(s):  
Self Assembly ◽  
Organic Molecule ◽  
High Efficiency ◽  
Photophysical Properties ◽  
Coupling Reaction ◽  
Ros Generation ◽  
Dead Cell ◽  
Minimal Invasiveness ◽  
Sonogashira Coupling Reaction ◽  
Potential Strategy

Cancer is one of the major diseases threatening human health. Traditional cancer treatments have notable side-effects as they can damage the immune system. Recently, phototherapy, as a potential strategy for clinical cancer therapy, has received wide attention due to its minimal invasiveness and high efficiency. Herein, a small organic molecule (PTA) with a D-A-D structure was prepared via a Sonogashira coupling reaction between the electron-withdrawing dibromo-perylenediimide and electron-donating 4-ethynyl-N,N-diphenylaniline. The amphiphilic organic molecule was then transformed into nanoparticles (PTA-NPs) through the self-assembling method. Upon laser irradiation at 635 nm, PTA-NPs displayed a high photothermal conversion efficiency (PCE = 43%) together with efficient reactive oxygen species (ROS) generation. The fluorescence images also indicated the production of ROS in cancer cells with PTA-NPs. In addition, the biocompatibility and photocytotoxicity of PTA-NPs were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and live/dead cell co-staining test. Therefore, the as-prepared organic nanomaterials were demonstrated as promising nanomaterials for cancer phototherapy in the clinic.

Sign in / Sign up

Export Citation Format

Share Document