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

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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Host-guest complexes of anionic porphyrin sensitizers with cyclodextrins

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424602000646 ◽

2002 ◽

Vol 06 (08) ◽

pp. 514-526 ◽

Cited By ~ 20

Author(s):

Jiří Mosinger ◽

Viktor Kliment ◽

Jan Sejbal ◽

Pavel Kubát ◽

Kamil Lang

Keyword(s):

Singlet Oxygen ◽

Specific Binding ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Fluorescence Emission ◽

Binding Constants ◽

Quantum Yields ◽

Hydroxyl Groups ◽

Triplet States ◽

Binding Modes

The photodynamic sensitizers zinc(II)- and palladium(II)-5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrins and 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin form 1:1 and/or 1:2 supramolecular complexes with native cyclodextrins (CD) and 2-hydroxypropyl cyclodextrins (hpCD) in aqueous neutral solutions. The formation of these assemblies causes a bathochromic shift of the porphyrin Soret band in the UV-vis spectra and a red shift of the fluorescence emission bands. The binding constants span over three orders of magnitude, from 8.1 × 102 M −1 to 5.4 × 105 M −1 (or 1.1 × 106 M −2) depending on the size of the CD cavity and on the functionalization by adding 2-hydroxypropyl groups. The highest binding constants were obtained for hpβCD and hpγCD. The Nuclear Overhauser spectroscopy signals (ROESY) revealed three binding modes: i) inclusion of the porphyrin 4-sulfonatophenyl or 4-carboxyphenyl groups via the secondary face of βCD and hpβCD with sulfonic or carboxylic groups oriented towards the primary hydroxyl groups. ii) inclusion of the porphyrin groups via the primary face of γCD and hpγCD. iii) non-specific binding of the porphyrin monomers or aggregates on the cyclodextrin exterior. The inclusion host-guest complexation via i) or ii) does not influence the inherent photophysical properties of the monomeric porphyrins such as the quantum yields of fluorescence, the triplet states, and the singlet oxygen formation. Due to the deaggregation effect of cyclodextrins, the inclusion complexes remain efficient supramolecular sensitizers of singlet oxygen even under conditions of extensive aggregation in aqueous solutions.

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Synthesis, characterization and photophysical properties of ferrocenyl and mixed sandwich cobaltocenyl ester linked meso-triaryl corrole dyads

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424617500614 ◽

2017 ◽

Vol 21 (10) ◽

pp. 646-657 ◽

Cited By ~ 2

Author(s):

B. Shivaprasad Achary ◽

A. R. Ramya ◽

Rajiv Trivedi ◽

P. R. Bangal ◽

L. Giribabu

Keyword(s):

Transient Absorption ◽

Photophysical Properties ◽

Heavy Atom ◽

Parent Compound ◽

Fluorescence Emission ◽

Soret Band ◽

Transient Absorption Spectroscopy ◽

Ferrocene Derivatives ◽

Time Resolved ◽

Design And Synthesis

We report here the design and synthesis of corrole-metallocene dyads consisting of a metallocene (either ferrocene (Dyad 1) or mixed sandwich [Formula: see text]-[C[Formula: see text]H[Formula: see text](COOH)]Co([Formula: see text]-C[Formula: see text]Ph[Formula: see text] (Dyad 2)) connected via an ester linkage at meso phenyl position. Both the dyads were characterized by [Formula: see text]H NMR, MALDI-TOF, UV-visible, fluorescence spectroscopies (steady-state, picosecond time-resolved), femtosecond transient absorption spectroscopy (fs-TA) and electrochemical methods. The absorption spectra of these dyads showed slight broadening and splitting of the Soret band that indicates a weak ground state interaction between the corrole macrocycle and metallocene part of the present donor–acceptor (D–A) system. However, in both the dyad systems, fluorescence emission of the corrole was quenched in polar solvents as compared to its parent compound 10-(4-hydroxyphenyl)-5,15-bis-(pentafluorophenyl ) corrole (Ph-Corr). The quenching was more pronounced in ferrocene derivatives than in cobaltocenyl derivatives. Transient absorption studies confirm the absence of photoinduced electron transfer from metallocene to correl for these dyad systems and the quenching of singlet state of corrole is found to enhance intersystem crossing due to heavy atom effect.

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The Structure of Polyisoprenes. V. Ultraviolet Absorption Spectra of Certain Carbalkoxy-Substituted 1,5-Dienes, and the Charge-Resonance Spectra of Glutaconic Ester Enolate Ions

Rubber Chemistry and Technology ◽

10.5254/1.3546810 ◽

1946 ◽

Vol 19 (1) ◽

pp. 23-33

Author(s):

L. Bateman ◽

H. P. Koch

Keyword(s):

Absorption Band ◽

Absorption Spectra ◽

Special Interest ◽

Crystalline State ◽

Marked Change ◽

Cyanine Dyes ◽

Structural Type ◽

Wave Absorption ◽

Long Wave ◽

Ester Enolate

Abstract Spectral evidence supports the conclusion reached in Part IV that ring-chain mesomerism in methyl and ethyl Δ1,5-hexadiene-l,1,3,3,4,4,6,6-octacarboxylates is nonexistent in solution, just as in the crystalline state. The data are not inconsistent with chain hyperconjugation in these molecules. The marked change in structural type that follows the addition of one molecule of hydrogen or hydrolytic reagent has been verified spectrographically. The spectra of methyl and ethyl α,γ-dicarboxyglutaconic esters and their sodium and cupric derivatives have been measured in various solvents, and their tautomeric behavior compared with that of other keto-enols. Of special interest is the intense long-wave absorption band of the enolate ions, which are recognized as simple structural analogs of the cyanine dyes giving rise to similar charge-resonance spectra. A preliminary comment is made on the present accepted structure of ethyl 6-ethoxy-α-pyrone-3:5-dicarboxylate.

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Effect of Some Substituents Increasing the Solubility of Zn(II) and Al(III) Phthalocyanines on Their Photophysical Properties

Bioinorganic Chemistry and Applications ◽

10.1155/2014/952632 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

A. A. Chernonosov ◽

E. A. Ermilov ◽

B. Röder ◽

L. I. Solovyova ◽

O. S. Fedorova

Keyword(s):

Absorption Spectra ◽

Structural Changes ◽

Water Solubility ◽

Transient Absorption ◽

Photophysical Properties ◽

Water Soluble ◽

Quantum Yields ◽

Carboxyl Groups ◽

Transient Absorption Spectra ◽

Photochemical Properties

Water solubility of phthalocyanines (Pcs) usually increases by the introduction of charged or carboxy substituents in the peripheral positions of the macrocycle. As a result, such structural changes influence their photophysical and photochemical properties as photosensitizers. Phthalocyanines substituted with four or eight terminal carboxyl groups and having in some cases additional eight positive charges (water soluble phthalocyanines) were studied in order to evaluate the spectroscopic and photophysical effects of these side residues on the chromophore properties. The quantum yield of singlet oxygen (O12) generation, the triplet-triplet absorption, and the transient absorption spectra were measured and linked to the structure of the substituents. It was shown that charged substituents did not change the quantum yields ofO12generation but decrease its lifetimes. The introduction of the charged substituents not only increases the water solubility but also significantly changes absorption, fluorescence, and transient absorption spectra of water soluble Pcs.

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Synthesis, photophysical properties and photodynamic antimicrobial activity of meso 5,10,15,20-tetra(pyren-1-yl)porphyrin and its indium(III) complex

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424621500462 ◽

2021 ◽

pp. A-F

Author(s):

Jackline Khisa ◽

Solomon Derese ◽

John Mack ◽

Edith Amuhaya ◽

Tebello Nyokong

Keyword(s):

Mass Spectrometry ◽

Antimicrobial Activity ◽

Fluorescence Quantum Yield ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Intersystem Crossing ◽

Free Base ◽

H Nmr ◽

Solvent Systems ◽

Dose Dependent

In this study, free-base meso 5,10,15,20-tetra(pyren-1-yl)porphyrin (H2TPyP) and its corresponding indium(III) complex (InClTPyP) were synthesized and characterized on the basis of mass spectrometry, 1H NMR spectroscopy and elemental analysis. InClTPyP was obtained in good yield by treating the free base H2TPyP with indium(III) chloride. Purification of these compounds was achieved through column chromatography using different solvent systems. Metallation of the free base to form a metallo-porphyrin afforded improved photophysical properties. There was a bathochromic shift in wavelength of absorption from the parent free base H2TPyP ([Formula: see text] = 431 nm) to metallated indium(III) complex ([Formula: see text] = 443 nm). The fluorescence quantum yield in H2TPyP was higher ([Formula: see text] = 0.131) than in InClTPyP ([Formula: see text] = 0.017) due to efficient intersystem crossing to the triplet manifold in the metallated porphyrin. Upon illumination, both H2TPyP and InClTPyP show effective dose dependent antimicrobial activity against Staphylococcus aureus with photoinactivation IC[Formula: see text] values of 27.89 and 16.67 [Formula: see text]M, respectively.

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Machine Learning Enables Highly Accurate Predictions of Photophysical Properties of Organic Fluorescent Materials: Emission Wavelengths and Quantum Yields

10.26434/chemrxiv.12111060.v3 ◽

2020 ◽

Author(s):

Cheng-Wei Ju ◽

Hanzhi Bai ◽

Bo Li ◽

Rizhang Liu

Keyword(s):

Machine Learning ◽

Density Functional ◽

Large Scale ◽

Fluorescent Dyes ◽

Photophysical Properties ◽

Quantum Yields ◽

Substitution Effects ◽

Quantum Mechanical ◽

Quantum Mechanical Calculations ◽

Fluorescent Materials

<div> <p>The development of functional organic fluorescent materials calls for fast and accurate predictions of photophysical parameters for processes such as high-throughput virtual screening, while the task is challenged by the limitations of quantum mechanical calculations. We establish a database covering >4,300 solvated organic fluorescent dyes and develop new machine learning (ML) approach aimed at efficient and accurate predictions of emission wavelength and photoluminescence quantum yield (PLQY). Our feature engineering has given rise to Functionalized Structure Descriptor (FSD) and Comprehensive General Solvent Descriptor (CGSD), whereby a highly black-box computational framework is realized with consistently good accuracy across different dye families, ability of describing substitution effects and solvent effects, efficiency for large-scale predictions and workability with on-the-fly learning. Evaluations with unseen molecules suggests a remarkable MAE of 0.13 for PLQY and 0.080 eV for emission energy, the latter comparable to time-dependent density functional theory (TD-DFT) calculations. An online prediction platform was constructed based on the ensemble model to make prediction in various solvents (https://www.chemfluor.top/). Our statistical learning methodology will complement quantum mechanical calculations as an efficient alternative approach for the prediction of these parameters.<br></p> </div><p> <br></p>

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Styryl-based new organic chromophores bearing free amino and azomethine groups: synthesis, photophysical, NLO, and thermal properties

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.16.189 ◽

2020 ◽

Vol 16 ◽

pp. 2282-2296

Author(s):

Anka Utama Putra ◽

Deniz Çakmaz ◽

Nurgül Seferoğlu ◽

Alberto Barsella ◽

Zeynel Seferoğlu

Keyword(s):

Schiff Base ◽

Schiff Bases ◽

Free Amino ◽

Second Harmonic ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Visible Region ◽

Amino Derivative ◽

Quantum Yields ◽

Thermal Stabilities

Herein we report the synthesis and characterization of a new series of styryl-based push-pull dyes containing a free amino group and their Schiff base derivatives. The dyes include the dicyanomethylene group as an acceptor and different para-substituted alkylamines as donors. Morever as a proton-sensitive group a pyridin-2-yl substituent was attached to the para-position of the phenyl moiety in both series of compounds. The photophysical properties of the dyes were examined in various solvents with different polarities and showed absorption in the visible region and green-red emission with low quantum yields. The absorption and the emission maxima were shifted bathocromically by increasing the solvent’s polarity. However, there was no correlation with the polarity parameters of the solvents. The pH-sensitive properties of all prepared Schiff bases were examined against TBAOH in DMSO, via deprotonation of the OH group in the salicylidene moiety and their reverse protonation was also investigated using TFA. The Schiff bases exhibited a bathochromic shift upon the addition of TBAOH to their solutions in DMSO. Therefore, they showed potential to be utilized as colorimetric and luminescence pH sensors. The second-order nonlinear optical (NLO) responses of the dyes were measured by the electric field-induced second harmonic (EFISH) generation method. The highest μβ values were obtained for the dyes bearing the julolidine donor as 1430 × 10−48 esu (for free amino derivative) and 1950 × 10−48 esu (for Schiff base derivative), respectively. The structural and electronic properties of the dyes as well as their NLO properties were further studied using DFT calculations. The thermal stabilities of all dyes were evaluated by thermogravimetric analysis (TGA). The TGA data showed that all dyes were thermally stable up to 250 °C.

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Synthesis and spectroscopic properties of β-triazoloporphyrin–xanthone dyads

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.155 ◽

2015 ◽

Vol 11 ◽

pp. 1434-1440 ◽

Cited By ~ 5

Author(s):

Dileep Kumar Singh ◽

Mahendra Nath

Keyword(s):

Fluorescence Spectra ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Cycloaddition Reaction ◽

Spectroscopic Characterization ◽

Spectroscopic Properties ◽

Dipolar Cycloaddition ◽

Free Base ◽

Acidic Conditions ◽

Derivatives Of

A novel series of β-triazoloporphyrin–xanthone conjugates and xanthone-bridged β-triazoloporphyrin dyads has been synthesized in moderate to good yields through Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction of copper(II) 2-azido-5,10,15,20-tetraphenylporphyrin or zinc(II) 2-azidomethyl-5,10,15,20-tetraphenylporphyrin with various alkyne derivatives of xanthones in DMF containing CuSO4 and ascorbic acid at 80 °C. Furthermore, these metalloporphyrins underwent demetalation under acidic conditions to afford the corresponding free-base porphyrins in good to excellent yields. After successful spectroscopic characterization, these porphyrins have been evaluated for their photophysical properties. The preliminary results revealed a bathochromic shift in the UV–vis and fluorescence spectra of these porphyrin–xanthone dyads.

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Phthalocyanine photophysics and photosensitizer efficiency on human embryonic lung fibroblasts

Journal of Porphyrins and Phthalocyanines ◽

10.1002/jpp.340 ◽

2001 ◽

Vol 05 (05) ◽

pp. 460-464 ◽

Cited By ~ 28

Author(s):

JOHN W. OWENS ◽

MARSHA ROBINS

Keyword(s):

Quantum Yield ◽

Photophysical Properties ◽

Fluorescence Emission ◽

Zinc Phthalocyanine ◽

Lung Fibroblasts ◽

Quantum Yields ◽

Cancer Drug ◽

Embryonic Lung ◽

Human Embryonic Lung ◽

Triplet Formation

This study correlates the photophysical properties of aluminum phthalocyanine tetrasulfonate (AlPcTs), zinc phthalocyanine tetrasulfonate (ZnPcTs), and phthalocyanine tetrasulfonate (PcTs) with their ability to kill human embryonic lung (HEL) cells. Photofrin, a proven anti-cancer drug, was used for comparison. The photophysical properties include fluorescence emission spectra, fluorescence quantum yields, singlet state and radiative lifetimes, quantum yield for triplet formation, and fluorescence rate constants. Results indicate that photodynamic efficacy correlates inversely with fluorescence quantum yield and fluorescence lifetime and directly with quantum yield for triplet formation.

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Solvatochromic Study of Supramolecular Amphiphile Based on Calix[4]arene Connected to a Fluorescent Benzofurazan Moiety at Lower Rim: Evaluation of Ground and Excited State Dipole Moments-=SUP=-*-=/SUP=-

Журнал технической физики ◽

10.21883/os.2020.12.50322.1028-20 ◽

2020 ◽

Vol 128 (12) ◽

pp. 1864

Author(s):

S. Joshi

Keyword(s):

Dipole Moment ◽

Excited State ◽

Ground State ◽

Fluorescence Spectra ◽

Dipole Moments ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Fluorescence Emission ◽

Wide Range ◽

Excited State Dipole Moment

Photophysical properties of a supramolecular amphiphile of calix[4]arene having benzofurazan moiety at the lower rim, L has been studied. Electronic absorption and fluorescence spectra of L have been recorded in wide range of solvents of different polarities and data were used to study solvatochromic properties. The ground state and the excited state dipole moment of L were estimated from the Bakhshiev's and Bilot-Kawaski's equations. High value of dipole moment is observed for excited state as compared to ground state value and this is attributed to more polar excited state of molecule. Also, fluorescence emission peak undergoes a bathochromic shift with increase in the polarity of the solvent, confirming π-> π* transition. Scanning electron microscopy reveals that the aggregation of L is increased on going from the polar to non polar solvents. Keywords: solvatochromism, benzofurazan, dipole moment, quantum yield, absorption, fluoresence.

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