Journal articles: 'Tetra phenyl porphyrins'

1

Ion, R. M., A. Planner, K. Wiktorowicz, and D. Frackowiak. "The incorporation of various porphyrins into blood cells measured via flow cytometry, absorption and emission spectroscopy." Acta Biochimica Polonica 45, no. 3 (September 30, 1998): 833–45. http://dx.doi.org/10.18388/abp.1998_4279.

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The incorporation of the five following porphyrins: meso-tetra(4-phenyl)porphyrin (TPP); meso-tetra(4-sulfonato-phenyl)porphyrin (TPPS4); meso-tetra(4-naphthyl)porphyrin (TNP); tri-sulfo-tetra-phenyl porphyrin (TPPS3) and tetra-sulfonato-naphthyl porphyrin (TNPS4) into human blood cells was investigated using flow cytometry, and absorption and emission spectroscopy. The percentage of stained cells, measured in a fluorescence cytometer, provided information on the efficiency of incorporation of fluorescent dye molecules into different types of cells. The yield of the incorporation of a dye was dependent on the type of dye and the solvent used for cell incubation. The degree of dye aggregation and ionization varied with the incubation medium, but dye molecules incorporated into cells seemed to be restricted to those in the monomeric state, exhibiting similar fluorescence yield. Of the three sulfonated porphyrins investigated only TPPS4 was efficiently incorporated into leukocytes. In the incubation solvent, this dye was in monomeric and neutral form. TPPS3 which was also in monomeric form, practically was not incorporated into cells. TPP and TNP dissolved in 5% aqueous dimethyl sulfoxide were present mostly in aggregated forms but they penetrated the cells with a high efficiency.

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Scheldt, W. Robert, Beisong Cheng, Allen G. Oliver, and John A. Goodwin. "Solid-state porphyrin interactions with oppositely charged peripheral groups." Journal of Porphyrins and Phthalocyanines 19, no. 12 (December 2015): 1256–61. http://dx.doi.org/10.1142/s1088424615501084.

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The crystallization and the crystal and molecular structure of a very slightly soluble electrostatically interacting pair of porphyrins is described. The tetra-anion 5,10,15,20-tetrakis-(4-sulfonatophenyl)-21,23H-porphyrin [H2TPPSO3][Formula: see text] and the tetra-cation 5,10,15,20-tetra([Formula: see text]-methylpyridyl)21H,23H-porphyrin [H2TMePyP][Formula: see text] are found to form an alternating one-dimensional stack that is stabilized by electrostatic interactions between the porphyrin rings but also by [Formula: see text] interactions between all substituted phenyl rings in the ensemble. The resulting interactions between the porphyrins is exceptionally tight.

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ION, Chim Rodica-Mariana, and Cristina MANDRAVEL. "THE PHOTODEGRADATION REACTION OF SOME PORPHYRINS." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 5, no. 5 (December 20, 1997): 111–29. http://dx.doi.org/10.48141/sbjchem.v5.n5.1997.109_1997.pdf.

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One of the most important but undesirable properties of the porphyrins is their oxidative photodegradation which can occur in non-polar solvents, under irradiation, and in the presence of molecular oxygen. The mechanism of this oxidative photodegradation implies singlet oxygen and different radical species. This paper is concerned with the mechanism of the photodegradation of some meso-tetra(4-X-phenyl)porphyrins(TXPP) and meso-tetra(4-X-1-naphtyl)porphyrins(TXNP), where X could have different organic structures (-NH2,-N02,-S03H,-OH,-OCH3,-CH3). Based on different spectral methods (UV-Vis and IR absorption spectroscopy, emission spectroscopy, X-ray diffraction, electronic microscopy, and mass spectrometry, we propose a photodegradation mechanism, and we evaluated the effect of some scavengers (2,6-di-tert-butyl-phenol (DTBF) for radical species, 1,3-diphenylisobenzofuran (DPBF) for singlet oxygen and nitro-blue tetrazolium (NBT) for superoxide anion) during the porphyrin photodegradation.

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George, Reama Chinedu, Nkem Torimiro, Oluwafemi Bamidele Daramola, and Afusat Ajoke Olajide. "Zinc, Tin and Silver Porphyrins (TPP, TCPP, TMPP, THPP, TPPS, TMPyP) as photosensitizers in antibacterial photodynamic therapy for chronic wounds: A screening study." Ethiopian Journal of Science and Technology 15, no. 2 (June 1, 2022): 187–207. http://dx.doi.org/10.4314/ejst.v15i2.6.

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Continuous proliferation of bacteria in a wound delays its healing process, and could further extend to becoming a chronic wound infection. The effectiveness of different porphyrins as a photosensitizer in antibacterial photodynamic therapy for the inactivation of some wound-colonizing bacteria was studied as a screening experiment. Meso-tetra(4-methoxyphenyl) porphyrin, (TMPP), meso-tetra(4-hydroxyphenyl) porphyrin (THPP), meso-tetra(4-carboxyphenyl) porphyrin, (TCPP), meso-tetra(N-methyl-4-pyridyl) porphyrin, (TMPyP) were synthesized, each complexed with zinc, tin and silver. The in-vitro and photo-toxicity properties of the porphyrins and their complexes were assessed on some selected wound colonizing multi-drug resistant bacterial strains (Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis, and Escherichia coli) using agar well diffusion method. Photo-toxicity of the compounds were investigated using a 100-Watt tungsten lamp while the in-vitro toxicity was carried out in the dark. The results were compared with previously reported work carried out by this group on meso-tetra(phenyl)porphyrin (TPP), meso-tetra(4-sulphonatophenyl) porphyrin, (TPPS) and their corresponding Zn, Sn and Ag complexes. Most of the porphyrins showed biocidal activities against three of the test isolates with an exception to Proteus sp. ZnTMPyP and ZnTHPP only showed photo-toxic activities against the four test isolates. While SnTHPP, ZnTPPS, ZnTCPP, and SnTCPP all exhibited both toxic and photo-toxic activities against all four bacterial isolates. The Ag-porphyrins had the poorest inactivation activity.

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Li, Yang, Hannah M. Rhoda, Anthony M. Wertish, and Victor N. Nemykin. "Organometallic pyrene-containing porphyrins: Synthesis, characterization, and non-covalent interactions with C60 fullerenes." Journal of Porphyrins and Phthalocyanines 20, no. 08n11 (August 2016): 1098–113. http://dx.doi.org/10.1142/s1088424616500735.

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A reaction between 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin and 1-bromopyrene resulted in the formation of 5,10,15,20-tetra[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (1), while cross-condensation between 4-(4-(pyrenyl-1)butoxy)benzaldehyde, ferrocenecaboxaldehyde, and pyrrole resulted in the formation of 5-ferrocenyl-10,15,20-tri[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (2), 5,10-diferrocenyl-15,20-di[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (3), and 5,15-diferrocenyl-10,20-di[4-(4-(pyrenyl-1)butoxy)phenyl]porphyrin (4). All pyrene-containing porphyrins were characterized by 1H NMR, UV-vis, MCD, and high-resolution ESI methods, while their electronic structures and the nature of the excited states were elucidated using density functional theory (DFT) and time-dependent DFT (TDDFT) calculations. The molecular structure of 1 and its fluorescence quenching upon the addition of C[Formula: see text] fullerene was also investigated using X-ray crystallography and steady-state fluorescence approaches.

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Alemohammad, Tahereh, Nasser Safari, and Samira Osati. "Effect of hydrogen bonding on catalytic activity of some manganese porphyrins in epoxidation reactions." Journal of Porphyrins and Phthalocyanines 15, no. 03 (March 2011): 181–87. http://dx.doi.org/10.1142/s1088424611003094.

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Mn (III)-tetra phenyl porphyrin-acetate (MnTPPOAc) and some kinds of meso-phenyl substituted porphyrins by hydroxyl groups and their Mn (III) complexes were synthesized. These Mn -porphyrins were used as catalyst in the epoxidation of various alkenes with tetra-n-butylammonium hydrogen monopersulfate (n- Bu4NHSO5 ) as oxidant and tetra-n-butylammonium acetate (n- Bu4NOAc ) as the axial ligand. The following order of catalytic activity was observed for cyclooctene: T(2,3-OHP)PMnOAc ≫ T(2,4,6-OHP)PMnOAc ≥ T(4-OHP)PMnOAc ≥ T(2,6-OHP)PMnOAc ≥ TPPMnOAc and T(2,3-OHP)PMnOAc ≫ TPPMnOAc > T(4-OHP)PMnOAc > T(2,4,6-OHP)PMnOAc > T(2,6-OHP)PMnOAc for other alkenes. Different activity and stability of the catalysts were interpreted based on the hydrogen bonding between hydroxyl groups with appropriate orientation on the meso-position of the phenyl groups and axial bases or oxidant. T(2,3-OHP)PMnOAc catalyst has shown optimal condition for effective hydrogen bonding. In the case of other catalysts, electronic and steric factors overcome the hydrogen bonding effect.

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HALVORSEN, INGAR, ERIK STEENE, and ABHIK GHOSH. "Resonance Raman marker bands of β-octahalogeno-meso-tetraarylmetalloporphyrins." Journal of Porphyrins and Phthalocyanines 05, no. 10 (October 2001): 721–30. http://dx.doi.org/10.1002/jpp.378.

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Soret-excited resonance Raman (RR) spectra are reported for some 40 nonplanar metalloporphyrin complexes. These include (i) copper β-octabromo-meso-tetra(para-X-phenyl)porphyrins, Cu [ Br 8 T (p- X - P ) P ] ( X = CH 3, H , F , CF 3, NO 2); (ii) copper β-octachloro-meso-tetra(para-X-phenyl)porphyrins, Cu [ Cl 8 T (p- X - P ) P ] ( X = H , CF 3); (iii) zinc β-octabromo-meso-tetraphenylporphyrin, Zn [ Br 8 TPP ], and zinc β-octasubstituted meso-tetrakis(pentafluorophenyl)porphyrins, Zn [ Y 8 TPFPP ] ( Y = CH 3, Cl , Br ); (iv) nickel β-octabromo-meso-tetra(para-X-phenyl)porphyrins, Ni [ Br 8 T (p- X - P ) P ] ( X = CH 3, H , F , Br , COOMe , CF 3, NO 2), with and without bis-ligated axial pyridine and imidazole ligands; (v) nickel β-octachloro-meso-tetra(para-X-phenyl)porphyrins, Ni [ Cl 8 T (p- X - P ) P ] ( X = CH 3, H , F , COOMe , CF 3, NO 2), again with and without bis-ligated axial pyridine ligands; and (vi) nickel octaethyltetraphenylporphyrin, Ni [ OETPP ], and palladium octaethyltetraphenylporphyrin, Pd [ OETPP ]. The spectra lead to the following conclusions. For a particular nonplanar porphyrin ligand, the high-frequency RR marker bands ν2 and ν4 downshift with increasing size of the coordinated metal ion, including a low- to high-spin transition for nickel porphyrins. In contrast, for a particular coordinated metal ion, these frequencies downshift with increasing nonplanarity of the porphyrin ligand, which in turn correlates with decreasing metal–nitrogen distances or the 'core size'. Similar results were also found for β-octaalkyl-meso-tetraphenylmetalloporphyrins by Shelnutt and coworkers. Thus, it appears that this complicated multiple-valued core size dependence of the high-frequency RR marker bands may be a generally shared property of all saddled metalloporphyrins. Variations in the electronic character of the metalloporphyrins resulting from variations in the para-substituents on meso-aryl groups do not result in significant shifts in the RR marker bands. The symmetric C meso – C phenyl stretching frequency (ν1) at approximately 1240 cm-1 is prominent in all the RR spectra except those of the low-spin Ni saddled porphyrins, for which they are relatively suppressed, and possible electronic-structural implications of this effect are discussed. In the low-frequency regions of the RR spectra of the compounds studied, the strongest band is roughly around 300 cm-1 and appears to be relatively safely assignable as γ16, a pyrrole tilting mode that strongly resembles the saddling mode in terms of atomic displacements.

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8

Shen, Liang, Xiaomei Wang, Bo Li, Wanli Jiang, Ping Yang, Shixiong Qian, Xutang Tao, and Minhua Jiang. "Two-photon absorption properties of substituted porphyrins." Journal of Porphyrins and Phthalocyanines 10, no. 03 (March 2006): 160–66. http://dx.doi.org/10.1142/s1088424606000193.

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The two-photon absorption (TPA) properties of two newly synthesized substituted porphyrins: 5,10,15,20-tetra-(4-pyrrolidinylphenyl)porphyrin (1) and 5,10,15,20-tetra-(4-diphenylamino-benzoic acid phenyl) porphyrin ester (3) were measured by the femtosecond Z-scan technique at 800 nm Ti : sapphire laser and by direct nonlinear optical transmission (NLT) using nanosecond Nd : YAG laser. The substituent effects, pumped wavelength and the environment upon the molecular TPA cross-section were investigated. It is found that the TPA cross-section for 3 is enhanced under excitation of 800 nm, relative to its precursor, 5,10,15,20-tetra(4-hydroxyphenyl) porphyrin (2), due to the former possessing extension conjugation of "D-A-core-A-D" molecular architecture. Also sample 3 obtained an increased TPA cross-section in rigid film relative to that in solution, suggesting that the enhancement is facilitated by the quasi-planar structure which allows direct interbranch conjugation throughout the molecule.

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Su, Qiwen, and Tamara D. Hamilton. "Extending mechanochemical porphyrin synthesis to bulkier aromatics: tetramesitylporphyrin." Beilstein Journal of Organic Chemistry 15 (May 22, 2019): 1149–53. http://dx.doi.org/10.3762/bjoc.15.111.

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Aldehydes with bulky substituents in the ortho-positions have been historically difficult in porphyrin synthesis, presumably owing to steric hindrance around the reactive site. We have used mechanochemistry for the simple, room-temperature synthesis of tetra-meso-substituted porphyrins. In the present study, mesitaldehyde undergoes acid-catalyzed mechanochemical condensation with pyrrole to give meso-tetrakis[2,4,6-(trimethyl)phenyl]porphyrin (TMP) after oxidation in solution. Yields are similar to those obtained using high-temperature porphyrin synthesis, although they remain significantly lower than some optimized room-temperature, solution-based methods. Yields of the mechanochemical synthesis were found to increase slightly upon longer exposure to an organic oxidizing agent in solution. This indicates that the mechanochemical condensation step may be more successful than initially realized. This work shows that mechanochemistry is a successful, simple, room-temperature method for producing tetra-meso-substituted porphyrins with bulky substituents.

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Nasrollahi, Rahele, and Saeed Zakavi. "Kinetics and mechanistic studies on the formation and reactivity of high valent MnO porphyrin species: mono-ortho or para-substituted porphyrins versus a di-ortho-substituted one." New Journal of Chemistry 42, no. 3 (2018): 1806–15. http://dx.doi.org/10.1039/c7nj04233g.

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High valent Mn(O) species of a series of electron-rich and -deficient meso-tetra(aryl)porphyrins (aryl = phenyl, 2-Cl-phenyl, 2-nitrophenyl, 2-Me-phenyl, 2-Br-phenyl, 2,6-di-Cl-phenyl 4-OMe-phenyl, 4-Me-phenyl, 4-Cl-phenyl and 4-pyridyl) were prepared at 273 K.

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Lopez, Marco A., and Martha A. De La Rosa. "Electronic effects on carbon monoxide dissociation from iron(II) tetraphenylporhyrins." Journal of Porphyrins and Phthalocyanines 09, no. 12 (December 2005): 821–29. http://dx.doi.org/10.1142/s1088424605000939.

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We report the kinetics of CO binding to a series of substituted ferrous tetra(4-X-phenyl)porphyrins ( X = CF 3, Cl , H , CH 3, OCH 3) in DMSO solvent using a mixture of 1,2-DMI/1-MeIm as proximal base. The CO dissociation rate constant increases with electron donation of the substituent X; the aggregate Hammett ρ value is -0.38. Using a Swain-Lupton analysis we determine the electronic effects to be transmitted 67% by through-bond or field effect and 33% by resonance. These results indicate that there is significant conjugation between the phenyl rings and the porphyrin core of iron tetraphenylporphyrin systems.

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Makarska-Bialokoz, Magdalena. "Spectroscopic study of associated systems formed between water-soluble cationic porphyrins or their copper (II) complexes and nucleic building blocks." Open Chemistry 11, no. 8 (August 1, 2013): 1360–67. http://dx.doi.org/10.2478/s11532-013-0267-7.

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AbstractThe association process between two water soluble cationic porphyrins, 5,10,15,20-tetrakis[4-(trimethyl-ammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H2TTMePP) and 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphine tetra-p-tosylate (H2TMePyP), as well as their Cu (II) complexes, with five series of nucleic agents has been studied using UV-VIS spectroscopy in aqueous solutions. During the titration with nucleic compounds the bathochromic effect of porphyrins absorption spectra can be observed as well as the hypochromicity of the Soret maximum. The association constants were calculated using a curve-fitting procedure (KAC of the order of magnitude of 103–105 mol−1). It has been shown that the interactions of H2TTMePP with nucleic agents are much stronger than interactions of H2TMePyP, which is most likely related to the kind and the size of the porphyrin substituent groups partaking in the process of stacking. The strength of the observed associated systems increases generally in a series: nucleic base

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Ou, Zhongping, Xueyan Chen, Lina Ye, Songlin Xue, Yuanyuan Fang, Xiaoqin Jiang, and Karl M. Kadish. "N-confusedmeso-tetraaryl-substituted free-base porphyrins: determination of protonation and deprotonation constants in nonaqueous media." Journal of Porphyrins and Phthalocyanines 19, no. 01-03 (January 2015): 251–60. http://dx.doi.org/10.1142/s1088424614501132.

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The protonation and deprotonation reactions for a series N-confused meso-tetraaryl-substituted free-base porphyrins containing electron-donating or electron-withdrawing substituents was monitored in CHCl3and DMF by UV-visible spectroscopy during titrations with trifluoroacetic acid or tetra-n-butylammonium hydroxide. The spectroscopic data was also used to calculate equilibrium constants for these reactions. The examined compounds are represented as (XPh)4NCPH2, where "NCP" represents the N-confused porphyrin π-conjugated macrocycle and X is a CH3O , CH3, H or Cl para-substituent on the four meso-phenyl rings (Ph) of the compound. The porphyrins can exist in two tautomeric forms depending upon the solvent and each tautomer undergoes two stepwise protonation reactions leading to formation of the mono- and bis-protonated porphyrins, [(XPh)4NCPH3]+and [(XPh)4NCPH4]2+. A single step deprotonation is observed for the same compounds in DMF and the product is assigned as [(XPh)4NCPH]-. Comparisons are made between UV-visible spectra of the protonated, neutral and deprotonated forms of the porphyrin and the effect of the porphyrin ring substituents and tautomeric form of the neutral porphyrin on the UV-visible spectra and protonation constants is discussed along with data from DFT calculations.

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Chen, Jian, Ji-Ming Hu, Zhi-San Xu, and Rong-Sheng Sheng. "Surface-Enhanced Resonance Raman Spectra Study of α,β,γ,δ-Tetra-(4-Trimethyl Ammonium Phenyl) Porphyrin." Applied Spectroscopy 47, no. 3 (March 1993): 292–95. http://dx.doi.org/10.1366/0003702934066659.

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In the present study, surface-enhanced resonance Raman scattering (SERRS) spectra of α,β,γ,δ-tetra-(4-trimethyl ammonium phenyl) porphyrin [T(4-TAP)P] were obtained. With increasing pH, the relative intensities of the bands at 890 and 1244 cm−1 decreased. These bands were attributed to γ(C-H) and δ(Cm-phenyl), respectively. The bands at 420 and 576 cm−1, which were assigned to γ(phenyl-ring), were enhanced. The molecular symmetry of T(4-TAP)P is discussed in terms of group theory. The bands at 1554 and 1496 cm−1 could be attributed to the vibrational modes of the porphyrin macrocycle; the bands at 1460, 1362, and 1330 cm−1 were assigned to ν(C-C) + δ(C-H), ν(C-N) + δ(C-H), and ν(C-N), respectively. All these bands change in band intensities, positions and widths, with the potential changing from +0.2 V to −0.2 V. It was concluded that the adsorbed porphyrins underwent partial incorporation with Ag from the electrode, and the adsorbate assumed a flat orientation on the silver electrode as well as the Ag colloid surface.

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Mojarrad, Aida G., and Saeed Zakavi. "Simple low cost porphyrinic photosensitizers for large scale chemoselective oxidation of sulfides to sulfoxides under green conditions: targeted protonation of porphyrins." Catalysis Science & Technology 8, no. 3 (2018): 768–81. http://dx.doi.org/10.1039/c7cy02308a.

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Pavanelli, André L. S., Leandro N. C. Máximo, Roberto S. da Silva, and Iouri E. Borissevitch. "Effect of Serum Albumin on Porphyrin-Quantum Dot Complex Formation, Characteristics and Spectroscopic Analysis." Nanomaterials 11, no. 7 (June 25, 2021): 1674. http://dx.doi.org/10.3390/nano11071674.

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The effect of bovine serum albumin (BSA) upon interaction between CdTe QD functionalized by 3-Mercaptopropionic Acid (CdTe-3-MPA QD) and two water soluble porphyrins: positively charged meso-tetra methyl pyridyl porphyrin (TMPyP) and negatively charged meso-tetrakis(p-sulfonato-phenyl) porphyrin (TPPS4), was studied in function of pH using the steady-state and time resolved optical absorption and fluorescence spectroscopies. It was shown that, depending on the charge state of the components, interaction with albumin could either prevent the formation of the QD…PPh complex, form a mixed QD…PPh…BSA complex or not affect PPh complexation with QD at all. The obtained results may be of interest for application in photomedicine.

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Sălăgeanu, Luminița, Delia Muntean, Horhat Florin George, Anca Lascu, Diana Anghel, Iulia Cristina Bagiu, and Eugenia Fagadar-Cosma. "Antimicrobial activity of different substituted meso-porphyrin derivatives." Revista Romana de Medicina de Laborator 28, no. 2 (April 1, 2020): 205–16. http://dx.doi.org/10.2478/rrlm-2020-0014.

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AbstractThe increasing resistance against classical antibiotic treatment forces the researchers to develop novel non-toxic antimicrobial agents. The aim of this study was to determine the antimicrobial properties of seven different porphyrins having distinctive hydrophobicity/hydrophilicity: P1 meso-tetra(4-methoxy-phenyl)porphyrin, P2 Zn(II)-meso-5,10,15,20-tetrapyridylporphyrin, P3 meso-tetra(p-tolyl)porphyrin, P4 5,10,15,20-tetraphenylporphyrin; P5 (5,10,15,20-tetraphenylporphinato) dichlorophosphorus(V) chloride, P6 5,10,15,20-tetrakis-(N-methyl-4-pyridyl) porphyrin-Zn(II) tetrachloride, P7 Zn(II)-5,10,15,20-meso-tetrakis-(4-aminophenyl)porphyrin. The meso-porphyrin derivatives were screened for their antimicrobial activity against six reference strains: Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, Pseudomonas aeruginosa ATCC27853 and Candida albicans ATCC 10231. The antimicrobial activity of these samples was evaluated by the agar disk diffusion method and dilution method, with the determination of the minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC). The most significant result is provided by the water-soluble P5 manifesting an obvious antimicrobial activity against Streptococcus pyogenes. On the other hand, P6 is a moderately active derivative against Streptococcus pyogenes and Escherichia coli and P7 presents moderate activity against Streptococcus pyogenes and Staphylococcus aureus. All the tested porphyrin bases, presenting hydrophobic character, have no antimicrobial activity under the investigated conditions. The common characteristics of the porphyrins that act as promising antimicrobial agents in the non-irradiated methods are: the cationic nature, the increased hydrophilicity and the presence of both amino functional groups grafted on the porphyrin ring and the coordination with Zn or phosphorus in the inner core.

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Ion, Rodica-Mariana. "Synthesis, photophysical properties and photocatalytic activity of tungsten porphyrin (TPPWCl4)." Journal of Porphyrins and Phthalocyanines 17, no. 06n07 (June 2013): 460–72. http://dx.doi.org/10.1142/s108842461350034x.

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Although tungsten porphyrins are known as mimicking models in biology, only a few papers about its chemical properties have been reported, the rarity of studies being attributed to the difficulties encountered in their synthesis due to their low stability. In this paper 5,10,15,20-tetra-p-phenyl-porphyrin tungsten(VI) chlorine (TPPWCl4) was studied, this metallo-porphyrin characterized by different analytical techniques: UV-vis, FTIR, ESR, mass spectrometry, including photophysical determination of its singlet oxygen quantum yield, too. Its photodegradation reaction with the mechanism and species involved into this destruction reaction processes is discussed, too. Also, in order to maintain its photostability, TPPWCl4has been incorporated into solid substrates, such as ZnO and TiO2, and these composites were subsequently tested in the photooxidation reaction of isoamylenes (2-methyl-2-butene and 2-methyl-1-butene mixture).

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Al-Shewiki, Rasha K., Carola Mende, Roy Buschbeck, Pablo F. Siles, Oliver G. Schmidt, Tobias Rüffer, and Heinrich Lang. "Synthesis, spectroscopic characterization and thermogravimetric analysis of two series of substituted (metallo)tetraphenylporphyrins." Beilstein Journal of Nanotechnology 8 (June 2, 2017): 1191–204. http://dx.doi.org/10.3762/bjnano.8.121.

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Subsequent treatment of H2TPP(CO2H)4 (tetra(p-carboxylic acid phenyl)porphyrin, 1) with an excess of oxalyl chloride and HNR2 afforded H2TPP(C(O)NR2)4 (R = Me, 2; iPr, 3) with yields exceeding 80%. The porphyrins 2 and 3 could be converted to the corresponding metalloporphyrins MTPP(C(O)NR2)4 (R = Me/iPr for M = Zn (2a, 3a); Cu (2b, 3b); Ni (2c, 3c); Co (2d, 3d)) by the addition of 3 equiv of anhydrous MCl2 (M = Zn, Cu, Ni, Co) to dimethylformamide solutions of 2 and 3 at elevated temperatures. Metalloporphyrins 2a–d and 3a–d were obtained in yields exceeding 60% and have been, as well as 2 and 3, characterized by elemental analysis, electrospray ionization mass spectrometry (ESIMS) and IR and UV–vis spectroscopy. Porphyrins 2, 2a–d and 3, 3a–d are not suitable for organic molecular beam deposition (OMBD), which is attributed to their comparatively low thermal stability as determined by thermogravimetric analysis (TG) of selected representatives.

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Wang, Bei-Bei, Huiping Zuo, John Mack, Poulomi Majumdar, Tebello Nyokong, Kin Shing Chan, and Zhen Shen. "Optical properties and electronic structures of axially-ligated group 9 porphyrins." Journal of Porphyrins and Phthalocyanines 19, no. 08 (August 2015): 973–82. http://dx.doi.org/10.1142/s108842461550073x.

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A series of group 9 metal tetra-(p-tolyl)-porphyrin ( M(ttp) , M = Co(II) , Rh(III) , Ir(III)) complexes with axial phenyl substituents have been synthesized and characterized. An aryl bromide cleavage reaction of transition metal complexes was used to prepare the complexes from Co(ttp) , Rh(ttp) Cl and Ir(ttp)COCl , respectively. Magnetic circular dichroism (MCD) spectroscopy and TD-DFT calculations have been used to study trends in the optical spectra and electronic structures. The effect of introducing different para-substituents on the phenyl substituents was examined. During fluorescence emission studies, phosphorescence was observed for the Ir(III) complexes in the near infrared (NIR) region.

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Guergueb, Mouhieddinne, Soumaya Nasri, Jihed Brahmi, Frédérique Loiseau, Florian Molton, Thierry Roisnel, Vincent Guerineau, Ilona Turowska-Tyrk, Kaïss Aouadi, and Habib Nasri. "Effect of the coordination of π-acceptor 4-cyanopyridine ligand on the structural and electronic properties of meso-tetra(para-methoxy) and meso-tetra(para-chlorophenyl) porphyrin cobalt(ii) coordination compounds. Application in the catalytic degradation of methylene blue dye." RSC Advances 10, no. 12 (2020): 6900–6918. http://dx.doi.org/10.1039/c9ra08504a.

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Preparation and UV/vis, IR, MS, ¹H NMR, cyclic voltammetry and molecular structures of two new Co(ii) complexes with para-methoxy-phenyl and para-chloro meso-porphyrins and 4-cyanopyridine ligand (1–2). Catalytic oxidation data of MB dye using 1–2.

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Albani, Guglielmo, Alberto Calloni, Madan S. Jagadeesh, Alberto Brambilla, Andrea Picone, Alessandro Lodesani, Lamberto Duò, Franco Ciccacci, Marco Finazzi, and Gianlorenzo Bussetti. "Ordered Porphyrin Arrays on Fe(001): An Enabling Technology for Future Spintronics." Proceedings 56, no. 1 (December 19, 2020): 25. http://dx.doi.org/10.3390/proceedings2020056025.

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We give evidence of the formation of an ordered array of tetra-phenyl porphyrins (TPP) when these molecules are deposited on top of oxygen-passivated Fe(001), namely the Fe(001)-p(1 × 1)O surface. We also prove that they are magnetically coupled with the substrate. The ordered molecular packing, together with the magnetic coupling, are fundamental conditions for application in organic spintronic devices. The system is studied by means of spin-resolved photoemission spectroscopies and scanning tunneling microscopy.

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Vicente, M. Graça H., Benjamin F. Edwards, Shankar J. Shetty, Yongjin Hou, and James E. Boggan. "Syntheses and preliminary biological studies of four meso-Tetra[(nido-carboranylmethyl)phenyl]porphyrins." Bioorganic & Medicinal Chemistry 10, no. 3 (March 2002): 481–92. http://dx.doi.org/10.1016/s0968-0896(01)00300-5.

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Srinivasan, Alagar, Bashyam Sridevi, Mereddy Venkat Ram Reddy, Seenichamy Jeyaprakash Narayanan, and Tavarekere K. Chandrashekar. "Improved synthesis of meso substituted 21-Oxa and 21-Thia tetra phenyl porphyrins." Tetrahedron Letters 38, no. 23 (June 1997): 4149–52. http://dx.doi.org/10.1016/s0040-4039(97)00807-1.

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Şen, Pınar, Catherine Hirel, Chantal Andraud, Christophe Aronica, Yann Bretonnière, Abdelsalam Mohammed, Hans Ågren, et al. "Fluorescence and FTIR Spectra Analysis of Trans-A2B2-Substituted Di- and Tetra-Phenyl Porphyrins." Materials 3, no. 8 (August 23, 2010): 4446–75. http://dx.doi.org/10.3390/ma3084446.

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Ang-Yang Yu. "Density Functional Theory Study of Meso-Tetra-Substituted Porphyrins: 3-Pyridyl Substitution for Phenyl." Russian Journal of Physical Chemistry A 94, no. 3 (March 2020): 604–7. http://dx.doi.org/10.1134/s0036024420030036.

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Dahal, Sanjay, and Israel Goldberg. "Solid-state supramolecular chemistry of porphyrins. Hydrogen-bonded networks and porous crystals ofmeso-tetra[4-(3,5-diaminotriazino)phenyl]porphyrin." Journal of Physical Organic Chemistry 13, no. 7 (2000): 382–87. http://dx.doi.org/10.1002/1099-1395(200007)13:7<382::aid-poc266>3.0.co;2-5.

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Albani, Guglielmo, Alberto Calloni, Andrea Picone, Alberto Brambilla, Michele Capra, Alessandro Lodesani, Lamberto Duò, Marco Finazzi, Franco Ciccacci, and Gianlorenzo Bussetti. "An In-Depth Assessment of the Electronic and Magnetic Properties of a Highly Ordered Hybrid Interface: The Case of Nickel Tetra-Phenyl-Porphyrins on Fe(001)–p(1 × 1)O." Micromachines 12, no. 2 (February 13, 2021): 191. http://dx.doi.org/10.3390/mi12020191.

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In this paper we focus on the structural, electronic, and magnetic properties of Ni tetra-phenyl-porphyrins (NiTPP) grown on top of Fe(001)–p(1 × 1)O. Ordered thin films of metal TPP molecules are potentially interesting for organic electronic and spintronic applications, especially when they are coupled to a ferromagnetic substrate. Unfortunately, porphyrin layers deposited on top of ferromagnetic substrates do not generally show long-range order. In this work, we provide evidence of an ordered disposition of the organic film above the iron surface and we prove that the thin layer of iron oxide decouples the molecules from the substrate, thus preserving the molecular electronic features, especially the HOMO-LUMO gap, even when just a few organic layers are deposited. The effect of the exposure to molecular oxygen is also investigated and an increased robustness against oxidation with respect to the bare substrate is detected. Finally, we present our results for the magnetic analysis performed by spin resolved spectroscopy, finding a null magnetic coupling between the molecules and the substrate.

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García-Pérez, César A., Carmina Menchaca-Campos, Miguel A. García-Sánchez, and Jorge Uruchurtu. "Electrochemical Capacitive Properties of Ny/PP/GO Electro-spun Composite Coating on Stainless Steel in Acid Media." European Journal of Engineering and Technology Research 7, no. 2 (March 30, 2022): 81–86. http://dx.doi.org/10.24018/ejeng.2022.7.2.2775.

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Composite materials were manufactured to obtain singular properties to be used as in electrochemical driven energy systems. An electrochemical evaluation was performed on electro-spun nylon 6,6 fibers (Ny), with different concentrations of tetra-para-amino-phenyl porphyrin (PP) and graphene oxide (GO) composite coating over stainless steel (SS), immersed in 1M H2SO4 aggressive sulfuric acid solution. Different film coatings behavior was obtained and compared using electrochemical impedance spectroscopy (EIS). Also, cyclic voltametry (CV) were performed on nylon/PP/GO composite coating system at different scan rates, and over film covered carbon cloth. For the electro-spun composite coating on stainless steel EIS, lower electro-spinning times present higher impedance, hence some corrosion protection. For greater electro-spinning times, larger capacitance values were observed. These were possibly due to thicker coating or mass transport adsorption-diffusion process through the composite film, respectively. For the composite coating, porphyrins, and graphene oxide interaction present ionic conductivity, reducing the impedance and promoting proton formation, property which could be used in charge storage systems.

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Aghabali, Amineh, and Nasser Safari. "Effects of methoxy-substituted metalloporphyrins in catalytic alkene epoxidation by n-Bu4NHSO5." Journal of Porphyrins and Phthalocyanines 14, no. 04 (April 2010): 335–42. http://dx.doi.org/10.1142/s1088424610002136.

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TPPMnOAc and four different kinds of manganese tetraphenylporphyrin acetates were synthesized using different numbers of methoxy substituents in various positions of the phenyl rings. These porphyrins were used as catalysts in the epoxidation of various alkenes with tetra-n-butylammonium hydrogen monopersulfate (n- Bu 4 NHSO 5) as the oxidant and imidazole as the axial base. The following order of catalytic activity was obtained: TPPMnOAc ≥ T (2,3- OMeP ) PMnOAc > T (4- OMeP ) PMnOAc > T (3,4- OMeP ) PMnOAc > T (2,4,6- OMeP ) PMnOAc . By studying the UV-vis spectra in the reaction solution, the stability of the applied methoxy porphyrins and the effect of this factor on obtained yields were investigated. Lower catalytic activity in some of the methoxy porphyrins emphasized steric effects and special hydrogen bonding among the reaction elements. However, the stability of T (2,3- OMeP ) PMnOAc under our reaction condition was considerable and high activity was observed. By adding small amounts of alcohol to the reaction solution, the effect of the solvent mixture was previewed and steps were taken to identify the active intermediate of the catalyst in these conditions.

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Li, Jianzhong, Tao Tang, Fan Li, and Min Li. "The synthesis and characterization of novel liquid crystalline, meso-tetra[4-(3,4,5-trialkoxybenzoate)phenyl]porphyrins." Dyes and Pigments 77, no. 2 (January 2008): 395–401. http://dx.doi.org/10.1016/j.dyepig.2007.07.008.

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32

Peng, Su-Hong, Li-Li Wang, Sha-Sha Cai, Hui-Qing Xiao, Xin-Tong Zhao, Hui Wang, and Hai-Yang Liu. "UV, FL and IR spectroscopic analysis of N-confused meso-tetra(methoxyphenyl)porphyrins." Journal of Porphyrins and Phthalocyanines 26, no. 03 (December 22, 2021): 195–202. http://dx.doi.org/10.1142/s1088424622500031.

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UV, FL and IR spectra of isomer A (in DCM) and isomer B (in DMAc) of N-confused 5,10,15,20-tetra([Formula: see text]-methoxyphenyl)porphyrin ([Formula: see text]-isomer, 1), N-confused 5,10,15,20-tetra([Formula: see text]-methoxyphenyl)porphyrin ([Formula: see text]-isomer, 2) and N-confused 5,10,15,20-tetra([Formula: see text]-methoxyphenyl)porphyrin ([Formula: see text]-isomer, 3) were investigated. Significant red shifts are observed from [Formula: see text]-isomer (1) to [Formula: see text]-isomer (3) in UV-vis absorption and fluorescence spectra. The fluorescence lifetime ([Formula: see text] of isomer A and isomer B of the samples (1, 2 and 3) are ca. 1.39[Formula: see text]1.79 ns and 1.68[Formula: see text]2.09 ns, respectively. In addition, the order of fluorescence quantum yield for isomer A is 1 >2 > 3, but for isomer B it is 1 < 3 <2. The isomer B of 2shows the strongest emission in accord with the strongest absorption. The isomer A of 1shows the strongest emission with the fluorescence quantum yield of 0.045, which is nearly double that of 3. The introduction of the methoxy group at the orthoposition increases steric hindrance, the molecular rigidity and the flow of [Formula: see text]-electron, thereby favourable to the fluorescence enhancement. The IR absorption peaks of 1, 2 and 3 were investigated and empirically assigned. The effects of the position of the substituents on the absorption frequency were also discussed. The absorption frequency of the C=C phenyl stretching in plane changed obviously by conjugative effect and steric effect when the methoxy group was at the orthoormetaposition in comparison with paraposition.

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33

Zolghadri, Samaneh, Hassan Yousefnia, Amir Reza Jalilian, and Yousef Fazaeli. "Production, quality control, biodistribution assessment and preliminary dose evaluation of [177Lu]-tetra phenyl porphyrin complex as a possible therapeutic agent." Brazilian Journal of Pharmaceutical Sciences 51, no. 2 (June 2015): 339–48. http://dx.doi.org/10.1590/s1984-82502015000200011.

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Due to interesting therapeutic properties of 177Lu and tumor avidity of tetraphenyl porphyrins (TPPs), 177Lu-tetraphenyl porphyrin was developed as a possible therapeutic compound. 177Lu of 2.6-3 GBq/mg specific activity was obtained by irradiation of natural Lu2O3sample with thermal neutron flux of 4 × 1013 n.cm-2.s-1. Tetraphenyl porphyrin was synthetized and labeled with 177Lu. Radiochemical purity of the complex was studied using Instant thin layer chromatography (ITLC) method. Stability of the complex was checked in final formulation and human serum for 48 h. The biodistribution of the labeled compound in vital organs of wild-type rats was studied up to 7 d. The absorbed dose of each human organ was calculated by medical internal radiation dose (MIRD) method. A detailed comparative pharmacokinetic study was performed for 177Lu cation and [177Lu]-TPP. The complex was prepared with a radiochemical purity: >97±1% and specific activity: 970-1000 MBq/mmol. Biodistribution data and dosimetric results showed that all tissues receive approximately an insignificant absorbed dose due to rapid excretion of the complex through the urinary tract. [177Lu]-TPP can be an interesting tumor targeting agent due to low liver uptake and very low absorbed dose of approximately 0.036 to the total body of human.

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Yun, Lin, Ling Zhen, Zikuan Wang, and Xuefeng Fu. "Aerobic oxidative N-dealkylation of secondary amines in aqueous solution catalyzed by rhodium porphyrins." Journal of Porphyrins and Phthalocyanines 18, no. 10n11 (October 2014): 937–43. http://dx.doi.org/10.1142/s108842461450076x.

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N-dealkylation demonstrates an important biochemical oxidation reaction by cytochrome P450 and other monooxygenases. In this article, catalytic oxidative N-dealkylation of secondary amines was achieved using rhodium(III) tetra (p-sulfonato-phenyl) porphyrin (( TSPP ) Rh III ) in aqueous solution with oxygen as the sole oxidant. Addition of benzaldehyde to trap primary amine product inhibited catalyst deactivation and dramatically increased reaction turnover numbers (TONs). Substrate scope examination suggested the reaction was performed with a preference for bulkier secondary amines. Kinetic study exhibited first-order kinetics with regard of ( TSPP ) Rh III catalyst. Results from the Hammett study gave a ρ value of -1.38, suggesting formation of an iminium ion intermediate in the rate determining step.

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35

Yu, Miao, Yu J. Zhang, Jian H. Shi, Guo F. Liu, and Hong J. Zhang. "Meso-tetra[(p-alkoxyl-m-ethyloxy)phenyl]porphyrins and their Transition Metal Complexes: Synthesis and Characterization." Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry 40, no. 6 (July 13, 2010): 404–9. http://dx.doi.org/10.1080/15533174.2010.492552.

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36

Wu, Ya-hong, Lin Chen, Jian Yu, Shan-ling Tong, and Yan Yan. "Synthesis and spectroscopic characterization of meso-tetra (Schiff-base substituted phenyl) porphyrins and their zinc complexes." Dyes and Pigments 97, no. 3 (June 2013): 423–28. http://dx.doi.org/10.1016/j.dyepig.2012.12.032.

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37

Kurochkin, Ivan Yu, Valentina A. Olshevskaya, Andrei V. Zaitsev, Nina I. Girichevac, and Georgy V. Girichev. "Vibrational Spectra of 5,10,15,20-Tetraphenylporphyrin (H2TPP) and Platinum(II) 5,10,15,20-Tetra(phenyl/pentafluorophenyl)porphyrins (PtTPP and PtTF5PP)." Macroheterocycles 14, no. 4 (2021): 334–41. http://dx.doi.org/10.6060/mhc224109g.

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38

Zheng, Wen Q., Wen Y. Liu, and Miao Yu. "Liquid-Crystalline Properties of Meso-tetra [(p-alkoxyl-m-ethyloxy)phenyl]Porphyrins and Their Transition Metal Complexes." Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry 43, no. 2 (December 28, 2012): 175–77. http://dx.doi.org/10.1080/15533174.2012.684254.

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Crusats, Joaquim, Josep Claret, Ismael Díez-Pérez, Zoubir El-Hachemi, Héctor García-Ortega, Raimon Rubires, Francesc Sagués, and Josep M. Ribó. "Chiral shape and enantioselective growth of colloidal particles of self-assembled meso-tetra(phenyl and 4-sulfonatophenyl)porphyrins." Chem. Commun., no. 13 (2003): 1588–89. http://dx.doi.org/10.1039/b303273f.

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SHE, Yuanbin, Lianshun FENG, Aixin WANG, and Xiuyan LI. "Synthesis of Substituted μ-Oxo-bis[tetra-phenyl porphyrinatoiron] Compounds from Free Base Porphyrins by a One-pot Method." Chinese Journal of Chemical Engineering 16, no. 3 (June 2008): 369–72. http://dx.doi.org/10.1016/s1004-9541(08)60090-7.

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41

Wang, Duo Yuan, Min Xue Hu, Ling Zhi Hu, Li Zheng Zhao, Zhen Zhong Lu, Yu Xin Nie, Kazuyuki Horie, and Shinjiro Machida. "Photophysical Properties of MESO-Phenyl-Tetra-Benzo-Porphyrins and Photon-Gated Spectral Hole Burning in Mixed Donor-Acceptor Systems at Low Temperature." Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals 291, no. 1 (December 1996): 223–33. http://dx.doi.org/10.1080/10587259608042751.

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42

Zuo, Guofang, Xiaoquan Lu, Zhonghua Xue, Baoqiang Lv, Yongsheng Wang, and Jingwan Kang. "Synthesis and Characterization of a Series of Thiol‐Derivatized Porphyrins and Electrocatalytic Reduction of Dioxygen by Cobalt(II)‐tetra‐[p‐(mercaptoprophyloxy)‐phenyl] Porphyrin (CoTMPP) on a Gold Support, Self‐Assembled Monolayers (SAMs)." Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry 36, no. 8 (September 1, 2006): 589–94. http://dx.doi.org/10.1080/15533170600908946.

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43

Desroches, Marie-Catherine, Sandrine Layac, Patrice Prognon, Philippe Maillard, David S. Grierson, Emmanuel Curis, Ioannis Nicolis, and Athena Kasselouri. "Speciation of New Tri- and Tetra-Glucoconjugated Tetrapyrrolic Macrocycles (Porphyrins and Chlorins): An Electronic Molecular Spectroscopy Study." Applied Spectroscopy 57, no. 8 (August 2003): 950–59. http://dx.doi.org/10.1366/000370203322258913.

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In this work, we study the physicochemical properties of some newly developed glycoconjugated photosensitizers that can be used in photodynamic therapy (PDT) of cancers: meso-tri-and tetra-( meta-O-β-d-glucosyloxyphenyl)porphyrins and meso-, tri-, and tetra-( meta-O-β-d-glucosyloxyphenyl)chlorins. Their properties are compared to the non-glycosylated hydroxylated parent compounds meso-tetra-( meta-hydroxyphenyl) porphyrin and meso-tetra-( meta-hydroxyphenyl)chlorin. It was found that at the ground state, all porphyrins present, independent of the substitution, have the same mean ionization constant (pKa = 2.7), corresponding to two indistiguishable steps of protonation of tetrapyrrolic nitrogens. On the other hand, in the case of chlorins, one proton process can be observed and the corresponding nitrogen exhibits a slightly superior basicity (pKa = 3.0) with respect to porphyrins. Hydroxylated compounds present a second transition at high pH corresponding to the ionization of phenol groups (pKa = 10.5). Consequently, all photosensitizers are not charged at physiological pH (≈7.4), and so the ionization process does not influence their activity in biological media. Ionization induces very important variations in photosensitizer absorption and emission spectra. For example, absorption in the red region (band V), one of the most important characteristics of a good photosensitizer, is only important for diprotonated porphyrins and neutral chlorins. As far as fluorescence emission is concerned, neutral chlorins are almost six times more fluorescent than the corresponding neutral porphyrins (Φchlorin/Φporphyrin ≈ 6). It should be emphasized that the spectra modifications induced by pH variations can find interesting applications in the optimization of visible and fluorescence detection in high-performance liquid chromatography (HPLC) as well as in the development of direct, rapid fluorimetric analytical methods.

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Plotnikova, Anna O., Yulia B. Ivanova, and Nugzar Zh Mamardashvili. "INVESTIGATION OF COORDINATION PROPERTIES OF 5,10,15,20-TETRA(4-OH-PHENYL) PORPHYRIN IN ACETONITRILE AND DIMETHYLFORMAMIDE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 60, no. 6 (July 19, 2017): 65. http://dx.doi.org/10.6060/tcct.2017606.5550.

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In the present work the reactions of basic interaction of 5,10,15,20-tetra(4-OH-phenyl) porphyrin in acetonitrile with the perchloric acid are studied by the method of spectrophotometric titration. And the chemical kinetics of ligand with zinc acetate in the dimethylformamide was carried out. The constant of the basic dissociation of the protonated acids of 5,10,15,20-tetra(4-OH-phenyl) porphyrin and kinetic parameters of the reaction of the formation of the zinc complex was obtained. The comparative analysis of our own obtained data and literature data according to the basic and coordination properties of 5,10,15,20-tetra(4-OH-phenyl) porphyrin and 5,10,15,20-tetrapheny porphyrin in acetonitrile and dimetilforamide in the range of 298-333K was carried out, which made it possible to draw a number of the interesting conclusions, which are concerned with the stabilization of the ionic forms of ligand in the acetonitrile and the dimethylformamide and the influence of solvent on the depth of the protonation of ligand and the kinetic rate of the formation of the corresponding zinc complexes. It is shown that the stabilization of the ionic forms of ligand upon transfer from the acetonitrile to dimethylformamide reduces the depth of the protonation of ligand, which is reflected in the decrease of the values of the dissociation constants of the cation forms of porphyrin, and the kinetic rate and the corresponding power expenditures for the reaction of the formation of ZnT(4-OH-Ph)P. It is shown that reactivity of ligand in the dipolar proton-free medium can be regulated by a change in the properties of this medium, which makes it possible to forecast the processes of the synthesis of compounds with the assigned properties.Forcitation:Plotnikova A.O., Ivanova Yu.B., Mamardashvili N.Zh. Investigation of coordination properties of 5,10,15,20-tetra(4-OH-phenyl) porphyrin in acetonitrile and dimethylformamide. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 6. P. 65-71.

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Sakthinathan, Subramanian, Subbiramaniyan Kubendhiran, Shen-Ming Chen, and P. Tamizhdurai. "Reduced graphene oxide/gold tetraphenyl porphyrin (RGO/Au–TPP) nanocomposite as an ultrasensitive amperometric sensor for environmentally toxic hydrazine." RSC Advances 6, no. 61 (2016): 56375–83. http://dx.doi.org/10.1039/c6ra09129f.

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Yu, Miao, Guo F. Liu, and Xiao L. Cui. "Synthesis, spectroscopy, surface photovoltage, and electrochemical properties of porphyrin compound liquid crystals." Journal of Porphyrins and Phthalocyanines 09, no. 04 (April 2005): 231–39. http://dx.doi.org/10.1142/s1088424605000290.

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Two series of porphyrin liquid crystalline compounds, meso-tetra-[(p-alkacyloxy-m-ethyloxy)phenyl]porphyrin ( TPAMEP ), and [5-(p-alkacyloxy) phenyl-10,15,20-tri-phenyl] porphyrin ( APTPP ) are synthesized and display a hexagonal columnar discotic columnar ( Col h ) phase. Their structure and properties were studied by elemental analysis, molar conductance, UV-visible and infrared spectra. Luminescence spectra of the compounds were discussed. Quantum yields of the Q band are in the region 0.007935-0.05847. The electrochemical studies show that the redox potentials do not change with the variation of the chain length. The surface photovoltage (SPV) response of the compounds was investigated by means of surface photovoltage spectroscopy (SPS) and field-induced surface photovoltage spectroscopy (FISPS), and the bands are analogous with the UV-visible absorption spectra.

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47

Checcoli, P., G. Conte, S. Salvatori, R. Paolesse, A. Bolognesi, M. Berliocchi, F. Brunetti, A. D’Amico, A. Di Carlo, and P. Lugli. "Tetra-phenyl porphyrin based thin film transistors." Synthetic Metals 138, no. 1-2 (June 2003): 261–66. http://dx.doi.org/10.1016/s0379-6779(02)01308-5.

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Reddy, D. Raghunath, and Bhaskar G. Maiya. "Bis(aryloxo) derivatives of tin(IV) porphyrins: synthesis, spectroscopy and redox activity." Journal of Porphyrins and Phthalocyanines 06, no. 01 (January 2002): 3–11. http://dx.doi.org/10.1142/s1088424602000026.

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Spectroscopic, electrochemical and fluorescence properties of five octahedral tin(IV) porphyrins ([( TpTP ) Sn ( O -m,p- C 6 H 3( CH 3)2)2] (1), [( TpTP ) Sn ( O -p- C 6 H 4( CH 3))2] (2), [( TpTP ) Sn ( O - C 6 H 5)2] (3), [( TpTP ) Sn ( O -p- C 6 H 4 O -o,p- C 6 H 3( NO 2)2)2] (4) and [( TpTP ) Sn ( O -p- C 6 H 4( NO 2))2] (5)) bearing electron donating/electron withdrawing aryloxo subunits as the axial ligands are investigated in detail. These complexes have been synthesized by the reaction of 5,10,15,20-tetra(4-methylphenyl)porphyrinato tin(IV) dihydroxide ([( TpTP ) Sn ( OH )2]) and either 3, 4-dimethylphenol, p-cresol, phenol, 4-(2,4-dinitrophenoxy)phenol or p-nitrophenol and were isolated in good-to-moderate yields. Analysis of the spectral data (FAB mass, IR, UV-vis and 1H NMR) of 1 - 5 suggests that the two trans axial aryloxo ligands are strongly bound in a symmetric manner at the tin center in these complexes. Specifically, the general symmetry observed in the 1H NMR spectra and the ring current effect experienced by the protons present on the axial ligands are revealing in this regard. Each porphyrin ring undergoes two successive, reversible/quasi-reversible, one-electron reductions in CH 2 Cl 2, 0.1 M TBAP. The bound nitroaromatic axial ligands of complexes 4 and 5 could also be reduced under the same set of experimental conditions. The wavelengths of maximum emission, the singlet energies and the Stokes’ shifts observed in the fluorescence spectra of 1 - 5 are close to the corresponding parameters of the reference porphyrin, [( TpTP ) Sn ( OH )2]. On the other hand, fluorescence intensities of complexes 1 - 4 are quenched in comparison with that of [( TpTP ) Sn ( OH )2] in three different solvents. A detailed analysis of the emission and redox potential data indicates that a photoinduced electron transfer from the axial aromatic subunit to singlet state of the basal tin(IV) porphyrin can, in principle, explain the fluorescence quenching observed in these donor-acceptor systems. The spectroscopic and redox features of these tin(IV) porphyrins are compared with those of the analogous phosphorus(V) porphyrins reported by us earlier.

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Zakavi, Saeed, Aida Ghanbelanie Mojarrad, and Saeed Rayati. "Substituent effects on the catalytic activity of a series of manganese meso-tetra(aryl)porphyrins: (2-, 3-, 4)-Pyridyl, 4-sulfonatophenyl and 3-sulfonato-4-methoxyphenyl groups compared to phenyl and 4-methoxyphenyl ones." Journal of Molecular Catalysis A: Chemical 363-364 (November 2012): 153–58. http://dx.doi.org/10.1016/j.molcata.2012.06.003.

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50

Calcavento, C., G. Conte, S. Salvatori, R. Paolesse, M. Berliocchi, A. Di Carlo, P. Lugli, and A. Sassella. "Charge injection and transport in tetra-phenyl-porphyrin." Synthetic Metals 138, no. 1-2 (June 2003): 255–60. http://dx.doi.org/10.1016/s0379-6779(02)01307-3.

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Journal articles on the topic 'Tetra phenyl porphyrins'

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