Synthesis, Characterization and Evaluating Photochemical Properties of Porphyrin-substituted Azobenzene Structure.

Herein a new azobenzene-substituted porphyrin molecule was synthesized, characterized and its optoelectronic properties were investigated by combining the high optoelectronic properties of porphyrin with the photosensitive properties of azobenzene. The carboxylic acid of azobenzene was covalently connected to -OH group of the porphyrin ring by using Steglich esterification. Molecular structure of the obtained azobenzene-porphyrin (8), was elucidated, by FTIR, 1 H and 13 C NMR and HRMS. After structural characterization absorption and emission, characteristics were determined in solvents that have different. And also, optical and fluorescence behaviors in the range of different acid pH with trans-cis photoisomerization behaviors were investigated in aqueous-THF solution in acid media.

Synthesis and Spectroscopic Properties of Oxazol-5-one- Substituted Phthalonitrile: A Novel Precursor for the Synthesis of Phthalocyanines.

Phthalonitirile-oxazol-5-ones (Pht-Ox), were synthesized with 4-(4-formylphenoxy) phthalonitrile and benzoylglycine derivatives. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1 H and 13 C NMR, UV-vis and MS spectral data. achieved. To obtain the photophysical data of the synthesized Pht-Ox derivatives were used spectrophotometric and spectrofluorimetric methods. Evaluation of the absorption and emission properties of the structures was carried out in three different solvents. Maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm- 1 M- 1 ) and Stoke's shifts (ΔλST; nm) of Pht-Ox derivatives were declared.

Tuning the Solid Phase Fluorescence Emission from Long Wavelength Visible to Near-Infrared in Oxazol-5-One Derivatives: Structure-Property Relationship, Theoretical and Experimental Studies.

Most of the fluorescent molecules among organic [Formula: see text]-conjugated materials show blue or green emission in the solid phase but few of them emit red-shifted visible and near-infrared light in the material science. To create molecules emitting for this feature, two π-conjugated oxazol-5-one derivatives containing donor (OCH3) and acceptor groups (NO2) were synthesized. Their optical and charge-transport properties were investigated through experimental and theoretical methods including the single crystal X-ray crystallography, Hirshfeld Surface Analysis, photophysical studies and Density Functional Theory (DFT), respectively. In addition, FT-IR, 1H-NMR, 13C-NMR spectroscopy, cyclic voltammetry (CV) measurements were performed. According to our results, both molecules may provide the significant pathway of development of long wavelength visible and red emissive features in solid phase with the aggregation induced enhanced emission (AIEE) properties particularly in the fields of OLEDs, optical communication, defence and bioimaging.

Phthalocyanines prepared from 4,5-dihexylthiophthalonitrile, a popular building block.

Phthalocyanines are tetrapyrrolic artificial porphyrinoids that play major roles in advanced biological and technological applications. Research on this family of dyes is particularly active in Türkiye, with many derivatives being prepared from 4,5-dihexylthiophthalonitrile DiSHexPN, which is one of the most popular noncommercially available building blocks for phthalocyanines. This review summarizes the phthalocyanines and their versatile properties and applications that have been published since 1994, when the synthesis of DiSHexPN was first described, to emphasize the importance of this building block in plentiful applications, all with biomedical or technological impact.

Synthesis and Characterization of Two Novel Oxazol-5-ones Derivatives and Their Multifunctional Properties; pH Sensitivity, Electropolymerizability and Antiproliferative Activity.

The aim of this study is to synthesize oxazol-5-one derivatives, which have multi-functional properties. Nomenclatures of newly synthesized molecules are 4-(4-N,N-diethylaminophenylmethylene)-2-(3-thienyl)oxazol-5-one (4a) and 4-(4-(1,4,7,10-tetraoxa-13-azacyclopentadecyl)phenylmethylene)-2-(3-thienyl)oxazol-5-one (4b). These two novel derivatives contain pH sensitive and polymerizable groups. 3-Thienyl group was attached to position-2 of the oxazol-5-one ring to provide electrochemical polymerization capability. pH sensing properties were provided by attaching p-N,N-diethylaminophenylmethylene and p-aza-15-crown-5-phenylmethylene groups to the arylmethylene moiety at position-4 of the ring. Target molecules were synthesized by classical process known as Erlenmeyer-Plöchl Azlactone Synthesis Erlenmeyer (Justus Liebigs Ann Chem 275:1-12, 1893), Rodrigues et al. (J Chem Educ 92:1543-1546, 2015) . After structural characterization of 4a and 4b, absorption and emission characteristics were determined in solvents that have different polarities. Difference in maximum absorption and emission wavelengths of the molecules related to solvent polarities were observed at around 6-7 nm and 35-36 nm respectively. In pH studies of the target derivatives in PVC polymer matrix, ratiometric changes were observed at isosbestic point around 398 nm. Polymeric depositions of the molecules (4a, 4b) were proved by using cyclic voltammetry, electrochemical impedance spectrometry studies and scanning electron microscope images. MTT assay studies showed significant results like, 4b derivative's strong cytotoxic activity on PC-3 (cancerous cell line) with IC50 value of 12.57 ± 0.41 µg/ml without exhibiting any cytotoxic effect on HEK293 (healthy cell line).

A Noble-Metal-Free Heterogeneous Photosensitizer-Relay Catalyst Triad That Catalyzes Water Oxidation under Visible Light.

An entirely earth-abundant chromophore-relay water oxidation catalyst triad system, which is robust and efficient at neutral pH, is presented. The synthesis involves the coordination of a porphyrin derivative to a bridging Fe(CN)5 group, which is then reacted with Co ions to prepare a covalently linked chromophore-Prussian blue analogue assembly. Light-driven water oxidation studies in the presence of an electron scavenger indicate that the triad is active and it maintains a steady activity for at least three hours. Transient absorption experiments and computational studies reveal that the Fe(CN)5 group is more than a linker as it takes part in electron-transfer and co-operates with porphyrin in the charge separation process.

Synthesis, Spectroscopic Characterization and Polymerization Abilities of Blue and Green Light Emitting Oxazol-5-one Fluorophores.

New fluorescent thiophenyl group containing oxazol-5-one fluorophores of 3a (4-(3-thiophenylmethylene)-2-phenyloxazol-5-one), 3b (4-(3-thiophenylmethylene)-2-(4-tolyl)oxazol-5-one) and 3c (4-(3-thiophenylmethylene)-2-(4-nitrophenyl)oxazol-5-one) were synthesized and characterized. The newly synthesized oxazol-5-ones absorption and fluorescence characteristics were studied in some solvents of varying polarities. The heterocyclic chromophores were fluorescent, with two of them, 3a and 3b, emitting blue light, whilst the other one, 3c, emitting green light. The emission maxima of the derivatives varied between 415 and 572 nm according as the extent of conjugation and solvent polarity. As solvent polarity increased, 3c derivatives emission spectra displayed a large bathochromic shift, which revealed the considerable change of the dipole moment of the fluorescent structure because of an intramolecular charge transfer interaction. Furthermore, oxazolones polymerization ability via the thiophenyl group linked to the oxazol-5-one heterocycle showed that copolymerization of 3a was achieved, but homopolymerization was not observed.

Spectroscopic, Structural and Density Functional Theory (DFT) Studies of Two Oxazol-5-one Derivatives.

In this study, two oxazol-5-one derivatives, C20H20N2O2 (1) and C21H22N2O2 (2), were synthesized by getting condensed p-N,N-diethylaminobenzaldehyde with two presented hippuric acid derivatives and in further studies they were analysed spectrochemically. Molecular and crystal structures of the compounds were determined by single-crystal X-ray diffraction and the results revealed that the molecular packing of the crystal structures were stabilized by weak intraand intermolecular interactions also with C-O∙∙∙π, C-H∙∙∙π and π∙∙∙π stacking interactions. Computational studies were also performed using DFT method at B3LYP/6-311G(d,p) level of theory. Vibrational modes and chemical shifts were calculated and compared with the experimental data. In addition, frontier molecular orbitals and molecular electrostatic potential surfaces were simulated. The calculated results show that the optimized geometries can well reproduce the crystal structure. Purpose of this study was to survey the effects of the reactants, which were condensed with each other to produce oxazol-5-one, upon the characteristic properties and crystal forms of the final oxazol-5-one.

New Chromophore Systems from Coumarin-Oxazol-5-one Combination.

Coumarin-oxazol-5-one (COX), 3a-d, were synthesized with 7-methoxy-2-oxo-2H-chromene-4-carbaldehyde and benzoylglycine derivatives. The characterizations of the COX derivatives by 1H NMR, FT-IR and elemental analysis were achieved. To obtain the photophysical data of the synthesized COX derivatives were used spectrophotometric and spectrofluorimetric methods. Evaluation of the absorption and emission properties of the structures was carried out in six different solvents. Maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm-1 M-1), Stoke's shifts (ΔλST; nm) and quantum yields (ϕF), of the COX derivatives were declared.

Axial binding and host-guest interactions of a phthalocyanine resorcinarene cavitand hybrid.

A Zn phthalocyanine-resorcinarene cavitand hybrid was prepared. The axial binding and host-guest interactions of this hybrid with a pyridinyl-pyrene were investigated by UV-vis and fluorescence spectroscopic means, revealing the encapsulation of the guest maintained by axial coordination to the Zn phthalocyanine. Energy transfer between the pyrene and the phthalocyanine was evidenced.

Emission-based optical carbon dioxide sensing with HPTS in green chemistry reagents: room-temperature ionic liquids.

We describe the characterization of a new optical CO(2) sensor based on the change in the fluorescence signal intensity of 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS) in green chemistry reagents--room-temperature ionic liquids (RTILs). As far as we are aware, this is the first time RTILs, 1-methyl-3-butylimidazolium tetrafluoroborate (RTIL-I) and 1-methyl-3-butylimidazolium bromide (RTIL-II), have been used as matrix materials with HPTS in an optical CO(2) sensor. It should be noted that the solubility of CO(2) in water-miscible ionic liquids is approximately 10 to 20 times that in conventional solvents, polymer matrices, or water. The response of the sensor to gaseous and dissolved CO(2) has been evaluated. The luminescence intensity of HPTS at 519 and 521 nm decreased with the increasing concentrations of CO(2) by 90 and 75% in RTIL-I and RTIL-II, respectively. The response times of the sensing reagents were in the range 1-2 min for switching from nitrogen to CO(2), and 7-10 min for switching from CO(2) to nitrogen. The signal changes were fully reversible and no significant hysteresis was observed during the measurements. The stability of HPTS in RTILs was excellent and when stored in the ambient air of the laboratory there was no significant drift in signal intensity after 7 months. Our stability tests are still in progress.