A three-step sequence strategy for facile construction of donor–acceptor type molecules: triphenylamine-substituted acenes

A new synthetic strategy was successfully developed for highly efficient construction of triphenylamine-substituted polycyclic aromatic hydrocarbons (PAHs), including anthracenes, tetraphenes, pentaphenes, and trinaphthylene. These molecules exhibited special structural characteristics, including donor–acceptor–donor (D–A–D) and donor–acceptor (D–A). Diverse aryl iodides coupled well with chlorinated 2-methyl benzaldehydes via a transient ligand-directed C–H bond arylation strategy to furnish various PAH precursors. The subsequent palladium-catalyzed Suzuki cross-couplings with 4-(diphenylamino)phenylboronic acid produced corresponding triphenylamine derivatives. Further, Brønsted acid promoted cycloaromatization generated the triphenylamine-substituted PAHs readily. The photophysical properties was investigated by UV–vis absorption and fluorescence emission spectroscope together with density functional theory (DFT) calculations.

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Palladium-Catalyzed Coupling Reaction of 3-Bromo Benzo[b]furan, -thiophene and -selenophene 2-Carboxaldehyde. Preparation of Tetracyclic Heteroaromatic Derivatives

Zeitschrift für Naturforschung B ◽

10.1515/znb-2006-0409 ◽

2006 ◽

Vol 61 (4) ◽

pp. 427-430 ◽

Cited By ~ 3

Author(s):

Gilbert Kirsch ◽

Stéphanie Deprets

Keyword(s):

Phenylboronic Acid ◽

Coupling Reaction ◽

Polycyclic Aromatic ◽

Palladium Catalyzed

3-Oxo-2,3-dihydrobenzo[b]furans, -thiophenes and -selenophenes 1a - c afforded the bromo-aldehydes 2 under Vilsmeier-Haack-Arnold conditions. Palladium-catalysed aryl-aryl coupling of 2 with o-formyl-phenylboronic acid allowed the formation of dialdehydes 3 which underwent McMurry cyclisation or pinacol condensation to yield polycyclic aromatic derivatives 4 or the dihydroxylated compounds 5

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Fluorene-Based Donor-Acceptor Copolymers Containing Functionalized Benzotriazole Units: Tunable Emission and their Electrical Properties

Polymers ◽

10.3390/polym12020256 ◽

2020 ◽

Vol 12 (2) ◽

pp. 256 ◽

Cited By ~ 1

Author(s):

Iván Torres-Moya ◽

Rebeca Vázquez-Guilló ◽

Sara Fernández-Palacios ◽

José Ramón Carrillo ◽

Ángel Díaz-Ortiz ◽

...

Keyword(s):

Density Functional ◽

Field Effect Transistors ◽

Photophysical Properties ◽

Suzuki Reaction ◽

Organic Field Effect Transistors ◽

Functional Theory ◽

Organic Optoelectronics ◽

Donor Acceptor ◽

Chain Lengths ◽

Tunable Emission

Monomers 4,7-dibromo-2H-benzo[d]1,2,3-triazole (m1) and 4,7-(bis(4-bromophenyl)ethynyl)-2H-benzo[d]1,2,3-triazole (m2) have been synthesized in good yields using different procedures. Monomers m1 and m2 have been employed for building new copolymers of fluorene derivatives by a Suzuki reaction under microwave irradiation using the same conditions. In each case different chain lengths have been achieved, while m1 gives rise to polymers for m2 oligomers have been obtained (with a number of monomer units lower than 7). Special interest has been paid to their photophysical properties due to excited state properties of these D-A units alternates, which have been investigated by density functional theory (DFT) calculations using two methods: (i) An oligomer approach and (ii) by periodic boundary conditions (PBC). It is highly remarkable the tunability of the photophysical properties as a function of the different monomer functionalization derived from 2H-benzo[d]1,2,3-triazole units. In fact, a strong modulation of the absorption and emission properties have been found by functionalizing the nitrogen N-2 of the benzotriazole units or by elongation of the π-conjugated core with the introduction of alkynylphenyl groups. Furthermore, the charge transport properties of these newly synthesized macromolecules have been approached by their implementation in organic field-effect transistors (OFETs) in order to assess their potential as active materials in organic optoelectronics.

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Preparation and Photophysical Properties of All-trans Acceptor–π-Donor (Acceptor) Compounds Possessing Obvious Solvatochromic Effects

Australian Journal of Chemistry ◽

10.1071/ch17021 ◽

2017 ◽

Vol 70 (9) ◽

pp. 1048

Author(s):

Yu-Lu Pan ◽

Zhi-Bin Cai ◽

Li Bai ◽

Sheng-Li Li ◽

Yu-Peng Tian

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Photophysical Properties ◽

Emission Spectra ◽

Photon Absorption ◽

Linear Absorption ◽

Functional Theory ◽

Two Photon Absorption ◽

Two Photon ◽

Donor Acceptor

A series of all-trans acceptor–π-donor (acceptor) compounds (BAQ, SFQ, BLQ, and XJQ) were conveniently synthesised and characterised by infrared, nuclear magnetic resonance, mass spectrometry, and elemental analysis. Their photophysical properties, including linear absorption, one-photon excited fluorescence, two-photon absorption, and two-photon excited fluorescence, were systematically investigated. All the compounds show obvious solvatochromic effects, such as significant bathochromic shifts of the emission spectra and larger Stokes shifts in more polar solvents. Under excitation from a femtosecond Ti : sapphire laser with a pulse width of 140 fs, they all exhibit strong two-photon excited fluorescence, and the two-photon absorption cross-sections in THF are 851 (BAQ), 216 (SFQ), 561 (BLQ), and 447 (XJQ) GM respectively. A combination of density functional theory (DFT) and time-dependent density functional theory (TDDFT) approaches was used to investigate the relationships between the structures and the photophysical properties of these compounds. The results show that they may have a potential application as polarity-sensitive two-photon fluorescent probes.

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Proton Triggered Colorimetric and Fluorescence Response of a Novel Quinoxaline Compromising a Donor-Acceptor System

Sensors ◽

10.3390/s18103433 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3433 ◽

Cited By ~ 2

Author(s):

Yogesh More ◽

Sachin Padghan ◽

Rajesh Bhosale ◽

Rajendra Pawar ◽

Avinash Puyad ◽

...

Keyword(s):

Density Functional ◽

Fluorescence Emission ◽

Emission Spectra ◽

Paper Strip ◽

Time Resolved ◽

Fluorescence Studies ◽

Color Changes ◽

Spectral Changes ◽

Donor Acceptor ◽

Strip Test

Quinoxaline-based novel acid-responsive probe Q1 was designed on the basis of a conjugated donor-acceptor (D-A) subunit. Q1 shows colorimetric and fluorometric changes through protonation and deprotonation in dichloromethane. With the addition of the trifluoroacetic acid (TFA), UV-vis absorption spectral changes in peak intensity of Q1 was observed. Moreover, the appearance of a new peaks at 284 nm 434 nm in absorption spectra with the addition of TFA indicating protonation of quinoxaline nitrogen and form Q1.H+ and Q1.2H+. The emission spectra display appearance of new emission peak at 515 nm. The optical property variations were supported by time resolved fluorescence studies. The energy band gap was calculated by employing cyclic voltammetry and density functional calculations. Upon addition of triethylamine (TEA) the fluorescence emission spectral changes of Q1 are found to be reversible. Q1 shows color changes from blue to green in basic and acidic medium, respectively. The paper strip test was developed for making Q1 a colorimetric and fluorometric indicator.

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Effects of Substituents on the Blue Luminescence of Disilane-Linked Donor‒Acceptor‒Donor Triads

Molecules ◽

10.3390/molecules24030521 ◽

2019 ◽

Vol 24 (3) ◽

pp. 521 ◽

Cited By ~ 5

Author(s):

Tsukasa Usuki ◽

Kenichiro Omoto ◽

Masaki Shimada ◽

Yoshinori Yamanoi ◽

Hidetaka Kasai ◽

...

Keyword(s):

Solid State ◽

Density Functional ◽

Photophysical Properties ◽

Density Functional Theory Calculations ◽

Molecular Structures ◽

Optical Measurements ◽

X Ray Diffraction ◽

Absolute Quantum Yield ◽

Donor Acceptor ◽

Metal Catalyzed

A series of disilane-linked donor‒acceptor‒donor triads (D‒Si‒Si‒A‒Si‒Si‒D) was synthesized to investigate the effects of substituents on the photophysical properties. The triads were prepared by metal-catalyzed diiodosilylation of aryl iodides using a Pd(P(t-Bu)3)2/(i-Pr)2EtN/toluene system that we previously developed. Optical measurements, X-ray diffraction analysis, and density functional theory calculations revealed relationships between the photophysical properties and molecular structures of these triads in solution and in the solid state. The compounds emitted blue to green fluorescence in CH2Cl2 solution and in the solid state. Notably, compound 2 showed fluorescence with an absolute quantum yield of 0.17 in the solid state but showed no fluorescence in CH2Cl2. Our findings confirmed that the substituent adjacent to the disilane moiety affects the conformations and emission efficiencies of compounds in solution and in the solid state.

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Ethyne Functionalized Meso-Phenothiazinyl-Phenyl-Porphyrins: Synthesis and Optical Properties of Free Base Versus Protonated Species

Molecules ◽

10.3390/molecules25194546 ◽

2020 ◽

Vol 25 (19) ◽

pp. 4546

Author(s):

Eva Molnar ◽

Emese Gál ◽

Luiza Găină ◽

Castelia Cristea ◽

Luminița Silaghi-Dumitrescu

Keyword(s):

Absorption Spectra ◽

Density Functional ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Fluorescence Emission ◽

Soret Band ◽

Quantum Yields ◽

Free Base ◽

Wave Absorption ◽

Long Wave

Synthesis, structural characterization and photophysical properties for a series of new trans-A2B2- and A3B-type ethynyl functionalized meso-phenothiazinyl-phenyl porphyrin derivatives are described. The new compounds displayed the characteristic porphyrin absorption spectra slightly modified by weak auxochromic effects of the substituents and fluorescence emission in the range of 651–659 nm with 11–25% quantum yields. The changes recorded in the UV-vis absorption spectra in the presence of trifluoroacetic acid (TFA) are consistent with the protonation of the two internal nitrogen atoms of the free-base porphyrin (19 nm bathochromic shift of the strong Soret band and one long wave absorption maxima situated in the range of 665–695 nm). Protonation of the phenothiazine substituents required increased amounts of TFA and produced a distinct hypsochromic shift of the long wave absorption maxima. The density functional theory (DFT) calculations of a porphyrin dication pointed out a saddle-distorted porphyrin ring as the ground-state geometry.

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Phenanthro[9,10-a]corannulene by one-step annulative π-extension of corannulene

Canadian Journal of Chemistry ◽

10.1139/cjc-2016-0467 ◽

2017 ◽

Vol 95 (3) ◽

pp. 329-333 ◽

Cited By ~ 35

Author(s):

Kenta Kato ◽

Yasutomo Segawa ◽

Kenichiro Itami

Keyword(s):

Crystal Structure ◽

Density Functional ◽

Photophysical Properties ◽

Coupling Reaction ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

X Ray ◽

Palladium Catalyzed ◽

One Step ◽

The One

The one-step π-extension of corannulene was achieved using a palladium-catalyzed C–H coupling reaction. The X-ray crystal structure and photophysical properties of the thus formed phenanthro[9,10-a]corannulene (1) were investigated, and the structural properties of 1 were examined by density functional theory calculations. In contrast to dibenzo[g,p]chrysene, the most stable structure of 1 was a butterfly-shaped structure, resulting from the bowl-shaped distortion of the corannulene moiety.

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Synthesis, Photophysical Characterization, and Sensor Activity of New 1,8-Naphthalimide Derivatives

Sensors ◽

10.3390/s20143892 ◽

2020 ◽

Vol 20 (14) ◽

pp. 3892

Author(s):

Stanislava Yordanova-Tomova ◽

Diana Cheshmedzhieva ◽

Stanimir Stoyanov ◽

Todor Dudev ◽

Ivo Grabchev

Keyword(s):

Density Functional Theory ◽

Metal Ions ◽

Fluorescence Intensity ◽

Density Functional ◽

Photophysical Properties ◽

Ph Dependence ◽

Fluorescence Emission ◽

Functional Theory ◽

Polar Media ◽

Tertiary Amino

Three new 1,8-naphthalimide derivatives M1–M3 with different substituents at the C-4 position have been synthesized and characterized. Their photophysical properties have been investigated in organic solvents of different polarity, and their fluorescence intensity was found to depend strongly on both the polarity of the solvents and the type of substituent at C-4. For compounds M1 and M2 having a tertiary amino group linked via an ethylene bridge to the chromophore system, high quantum yield was observed only in non-polar media, whereas for compound M3, the quantum efficiency did not depend on the medium polarity. The effect of different metal ions (Ag+, Ba2+, Cu2+, Co2+, Mg2+, Pb2+, Sr2+, Fe3+, and Sn2+) on the fluorescence emission of compounds M1 and M2 was investigated. A significant enhancement has been observed in the presence of Ag+, Pb2+, Sn2+, Co2+, Fe3+, as this effect is expressed more preferably in the case of M2. Both compounds have shown significant pH dependence, as the fluorescence intensity was low in alkaline medium and has been enhanced more than 20-fold in acidic medium. The metal ions and pH do not affect the fluorescence intensity of M3. Density-functional theory (DFT) and Time-dependent density-functional theory (TDDFT) quantum chemical calculations are employed in deciphering the intimate mechanism of sensor mechanism. The functional properties of M1 and M2 were compared with polyamidoamine (PAMAM) dendrimers of different generations modified with 1,8-naphthalimide.

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A New Tool in the Quest for Biocompatible Phthalocyanines: Palladium Catalyzed Aminocarbonylation for Amide Substituted Phthalonitriles and Illustrative Phthalocyanines Thereof

Catalysts ◽

10.3390/catal8100480 ◽

2018 ◽

Vol 8 (10) ◽

pp. 480 ◽

Cited By ~ 2

Author(s):

Vanessa Tomé ◽

Mário Calvete ◽

Carolina Vinagreiro ◽

Rafael Aroso ◽

Mariette Pereira

Keyword(s):

Photophysical Properties ◽

Peptide Bond ◽

Spectroscopic Characterization ◽

Aryl Halides ◽

Biologically Active ◽

Initial Assessment ◽

Pharmaceutical Drugs ◽

Synthetic Strategy ◽

New Strategy ◽

Palladium Catalyzed

The amide peptide bond type linkage is one of the most natural conjugations available, present in many biological synthons and pharmaceutical drugs. Hence, aiming the direct conjugation of potentially biologically active compounds to phthalocyanines, herein we disclose a new strategy for direct modulation of phthalonitriles, inspired by an attractive synthetic strategy for the preparation of carboxamides based on palladium-catalyzed aminocarbonylation of aryl halides in the presence of carbon monoxide (CO) which, to our knowledge, has never been used to prepare amide-substituted phthalonitriles, the natural precursors for the synthesis of phthalocyanines. Some examples of phthalocyanines prepared thereof are also reported, along with their full spectroscopic characterization and photophysical properties initial assessment.

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Exploring the optoelectronic properties of a chromene-appended pyrimidone derivative for photovoltaic applications

Open Chemistry ◽

10.1515/chem-2019-0119 ◽

2019 ◽

Vol 17 (1) ◽

pp. 1167-1172

Author(s):

Mohammed A. Assiri

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Photophysical Properties ◽

Fluorescence Emission ◽

Emission Spectra ◽

Solvent Polarity ◽

Frontier Molecular Orbital ◽

Electronic Effects ◽

Fluorescence Emission Spectra ◽

Functional Theory

AbstractIn the present study, a chromene-appended pyrimidone derivative (PBA) has been synthesized in order to account for the relationship between chemical structure and charge transport properties. The optical properties of PBA were studied in different solvents; it displays a weak emission profile in polar protic solvents but is highly emissive in polar aprotic solvents. Quantum chemical approaches on this molecule were performed in detail to highlight the importance of and to better understand the structural and electronic effects of introducing substituted pyrimidone rings in a polyaromatic molecule to support the development of new optoelectronic and photovoltaic devices. We shed light on the frontier molecular orbital, electron injection, electronic coupling constant, light harvesting efficiency, and photophysical properties of PBA by using density functional theory and time domain density functional theory. The absorption spectra (λa) and fluorescence emission spectra (λf) were computed in different solvents (Methanol, Ethanol, Butanol, Hexane, Chloroform and DMF) at the TD-B3LYP/6-31G** and TD-PBE/6-31G** levels of theory, and it was determined that the TD-B3LYP/6-31G** level is more accurate in the reproduction of experimental λa and λf in various solvents. Furthermore, no significant effect was observed on the λa and λf by changing the solvent polarity.

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