Articles de revues : « Extended porphyrin »

1

Yan, Jia Ying, Ya Qing Feng, Fang Qun Zhou, Yi Wen Chang et Bao Zhang. « Studies on Sonogashira Coupling Reaction of Dibenzoporphyrin ». Advanced Materials Research 581-582 (octobre 2012) : 317–21. http://dx.doi.org/10.4028/www.scientific.net/amr.581-582.317.

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Changing the proportion of NBS and porphyrin, dibromination of β, β’- π-extended porphyrins was found to selectively occur to the β and β’ position of the porphyrins which is antipotal to the fused aromatic ring. Subsequent Sonogashira coupling of the resultant dibromoporphyrin introduced a carboxylphenylethynyl group to the π-extended porphyrin and the π conjugation was thus further elongated. The coupling products have shown a broadening and a red-shift of the Soret band and Q bands in the UV-Vis absorption spectra compared with the π-extended porphyrin starting materials and the original unmodified porphyrins.

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Cheprakov, Andrei V., et Mikhail A. Filatov. « The dihydroisoindole approach to linearly annelated π-extended porphyrins ». Journal of Porphyrins and Phthalocyanines 13, n^o 03 (mars 2009) : 291–303. http://dx.doi.org/10.1142/s1088424609000383.

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The dihydroisoindole strategy for the synthesis of linearly annelated π-extended porphyrins is a common approach to tetrabenzo-, tetranaphtho-, and tetraanthraporphyrins with variable functionality and substitution patterns. This method implies the use of a common type of precursors involving the 4,7-dihydroisoindole moiety, which are the closest possible stable relatives of the unstable isoindole, benzoisoindole and naphthoisoindole. A key feature of this strategy is the unprecedented mildness of the final oxidative aromatization step, which accounts for synthetic versatility, better functional group tolerance and high purity of the products. Many new linearly annelated π-extended porphyrins of the tetrabenzo-, tetranaphtho-, and tetraanthraporphyrin families were produced and characterized for the first time, including soluble planar and highly emissive 5,15-diaryl derivatives. The double bond of the dihydroisoindole fragment can also be useful for further modification of the porphyrin by means of addition of cycloaddition reactions, leading to new, previously inaccessible porphyins bearing multiple halide, hydroxy, or acetoxy groups at the periphery.

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Brewer, Ashley, Matthew Lacey, John R. Owen, Iris Nandhakumar et Eugen Stulz. « Supramolecular hetero-porphyrin SWNT complexes ». Journal of Porphyrins and Phthalocyanines 15, n^o 04 (avril 2011) : 257–63. http://dx.doi.org/10.1142/s1088424611003227.

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The complexation of single walled carbon nanotubes (SWNTs) with neutral, anionic and cationic porphyrins has been investigated under identical complex forming conditions. The determination of the porphyrin loading reveals large differences depending on the nature of the porphyrin used. Combinations of different porphyrins to form mixed hetero-porphyrin complexes shows that the mixture of a cationic and anionic porphyrin results in loading which is an order of magnitude larger than in all other complexes. This complex also exhibits high adsorption and emission intensities and can be regarded as an extended co-operative binary ionic (CBI) solid. The complexes were further studied using Raman spectroscopy, elemental analysis, AFM and cyclic voltammetry.

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Wang, Hong, Yi Hu, Michael Thomas, Ajyal Alsaleh et Francis D'Souza. « (Invited) Pi-Extended Porphyrins : Synthesis, Functionalization and Applications in Dye-Sensitized Solar Cells ». ECS Meeting Abstracts MA2022-01, n^o 13 (7 juillet 2022) : 903. http://dx.doi.org/10.1149/ma2022-0113903mtgabs.

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pi-Extended porphyrins are of broad interest due to their unique combination of photophysical, optoelectronic, and physicochemical properties, and their potential applications in many areas ranging from biomedicine to organic electronics.1,2 In this talk, three series of beta-functionalized push-pull pi-extended porphyrins as sensitizers for dye-sensitized solar cells will be presented.3-5 Our studies show significant push-pull effects for these porphyrins. DFT calculations suggest that the inclusion of ethynylphenyl bridge between the donating group and the porphyrin core significantly segregate the frontier orbitals. It has also been found that dimethylaminophenyl group cause dye decomposition on solar cells. To solve the dye degradation problem, porphyrin dyes with tertiary arylamine groups serving as the donor groups were prepared. Our studies show that tertiary arylamine groups are able to stabilize the dyes adsorbed on the solar cells. Their photovoltaic performances were tested in dye-sensitized solar cells. In this talk, the synthesis and characterization of pentacene-fused (linearly conjugated) and pentaquinone-fused (cross-conjugated) porphyrin oligomers will also be presented.6 These pentacene-fused porphyrins are much more stable than their corresponding pentacene derivatives. The electronic absorption spectra and transit spectroscopy of these porphyrins indicate highly interactive multiple p-systems. The electronic and optical properties of these p-extended porphyrins were measured using UV-Vis spectroscopy, life-time and steady state fluorescence spectroscopy, and cyclic voltammetry. DFT calculations were also performed for these porphyrins.

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de Torres, Miriam, Sergey Semin, Ilya Razdolski, Jialiang Xu, Johannes A. A. W. Elemans, Theo Rasing, Alan E. Rowan et Roeland J. M. Nolte. « Extended π-conjugated ruthenium zinc–porphyrin complexes with enhanced nonlinear-optical properties ». Chemical Communications 51, n^o 14 (2015) : 2855–58. http://dx.doi.org/10.1039/c4cc09592h.

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Chevrier, Michèle, Sébastien Richeter, Olivier Coulembier, Mathieu Surin, Ahmad Mehdi, Roberto Lazzaroni, Rachel C. Evans, Philippe Dubois et Sébastien Clément. « Expanding the light absorption of poly(3-hexylthiophene) by end-functionalization with π-extended porphyrins ». Chemical Communications 52, n^o 1 (2016) : 171–74. http://dx.doi.org/10.1039/c5cc06290j.

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Thomas, Michael B., R. G. Waruna Jindasa, Yi Hu, Benjamin Schmitz, Hong Wang et Francis D’Souza. « Investigation of the push–pull effects on β-functionalized zinc porphyrin coordinated to C60 donor–acceptor conjugates ». Canadian Journal of Chemistry 96, n^o 9 (septembre 2018) : 881–89. http://dx.doi.org/10.1139/cjc-2017-0416.

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Two novel β-functionalized push–pull zinc porphyrins with amine or phenyl push-groups and cyclic imide or carboxylic esters pull-groups have been newly synthesized for light energy harvesting applications. The ethynylphenyl spacers extended the conjugation of the porphyrin π-systems, as reflected by their red-shifted absorbance and fluorescence spectra. Computational studies performed at the B3LYP/6-31G* level indicated no steric hindrance between the porphyrin π-system and the substituents. The calculated HOMO and LUMO orbitals displayed significant delocalization in 1, where the electron density in the HOMO was localized over the push groups, whereas the LUMO was extended over the porphyrin π- and pull-groups. On the other hand, 2 did not display significant orbital segregation, which is attributed to its weaker push–pull character. Electrochemical studies revealed smaller HOMO–LUMO gaps for the push–pull zinc porphyrins. As a consequence of the push–pull effects, reduction in fluorescence intensity and lifetime was observed. Femtosecond transient absorption spectral studies revealed successful formation of singlet excited state in both of the push–pull porphyrins. Donor–acceptor conjugates were subsequently built and characterized by coordinating an electron acceptor, C60Im, via metal–ligand axial coordination. Efficient photo-induced charge separation in both donor–acceptor conjugates was witnessed wherein the charge-separated states persisted tens of nanoseconds prior returning to the ground state.

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Warrener, Ronald N., Hongsui Sun et Martin R. Johnston. « Position-Addressable Nano-Scaffolds. II. The Introduction of One, Two, or Three Addressable Succinimide Linkage Points onto the Under-Surface of ‘Southern’ Cavity Bis-Porphyrins ». Australian Journal of Chemistry 56, n^o 4 (2003) : 269. http://dx.doi.org/10.1071/ch02219.

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Cavity bis-porphyrins containing up to three addressable succinimide rings on the underface are reported for the first time. This is achieved by site-selective addition of o-chloranil to the 7-oxanorbornene π-bond of O-bridged sesquinorbornadienosuccinimide (1a) to form a scaffold α-dione, followed by condensation with porphyrindiamine (12) to produce a porphyrin-containing norbornene BLOCK (13) incorporated a succinimide ring fused to the underside. Dual 1,3-dipolar coupling of (13) with alicyclic bis-epoxides (15) formed the cavity bis-porphyrins (16) containing two succinimide rings while similar 1,3-dipolar coupling with succinimide-containing bis-epoxide (17) gave the extended cavity bis-porphyrin (18) having three succinimide rings within the cavity section. A similar cycloaddition/condensation strategy provides the shortest route to cavity bis-porphyrins containing a single succinimide ring yet reported.

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Hamer, Mariana, Rolando M. Caraballo, Peter J. Eaton et Craig Medforth. « Nanoparticles as template for porphyrin nanostructure growth ». Journal of Porphyrins and Phthalocyanines 23, n^o 04n05 (avril 2019) : 526–33. http://dx.doi.org/10.1142/s1088424619500469.

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Porphyrins and metalloporphyrins are one of the most widely studied platforms for the construction of supramolecular structures. These compounds have an extended aromatic system that allows [Formula: see text]–[Formula: see text] stacking interactions which, together with hydrogen bonds, electrostatic forces and the formation of inter-metallic complexes arising from peripheral groups, offer a versatile platform to control the self-assembly mechanism. In this work, we present the study of nanostructures formed by self-assembly of the water-soluble porphyrins meso-tetra([Formula: see text]-methyl-4-pyridyl)porphyrin (TMPyP) and meso-tetra(4-sulfonatophenyl)porphyrin (TPPS) in the presence of hard nanotemplates. Different nanoparticles (silica, gold, and polystyrene), concentrations and synthetic procedures were explored. The obtained materials were characterized by SEM and AFM microscopies, UV-vis absorption spectroscopy and dynamic light scattering measurements. A clear modification of the SiO2 NP surface roughness using one-pot synthesis was observed. The results were variable depending on the porphyrin–surface interactions and concentrations used. At lower porphyrin concentrations, a shift of the Soret band was observed, while at higher concentrations, free NS were formed. This reflects a competition between surface and solution directed self-assembly.

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Vannelli, Tommaso A., et Timothy B. Karpishin. « Neocuproine-Extended Porphyrin Coordination Complexes ». Inorganic Chemistry 38, n^o 10 (mai 1999) : 2246–47. http://dx.doi.org/10.1021/ic9812914.

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Ou, Zhongping, Wenbo E, Jianguo Shao, Paul L. Burn, Craig S. Sheehan, Robin Walton, Karl M. Kadish et Maxwell J. Crossley. « Electrochemical and spectroelectrochemical properties of building blocks for molecular arrays : reactions of quinoxalino[2,3-b]porphyrins containing metal(II) ions ». Journal of Porphyrins and Phthalocyanines 09, n^o 02 (février 2005) : 142–51. http://dx.doi.org/10.1142/s1088424605000216.

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Quinoxalino[2,3-b]porphyrins are laterally-extended porphyrins with aromatic ring systems fused to the β,β'-positions of a pyrrolic ring of the macrocycle. They are building blocks for coplanar laterally-extended oligoporphyrins with applications in molecular electronics. The electrochemistry and spectroelectrochemistry of four such quinoxalinoporphyrins containing metal(II) ions and one free-base quinoxalinoporphyrin dissolved in nonaqueous media have been investigated and the data are compared to that seen for the same derivatives of the parent macrocycle lacking the fused quinoxaline ring. The investigated compounds are represented as (P)M and (PQ)M, where P = 5 ,10,15,20-tetrakis(3,5-di-tert-butylphenyl)porphyrin, PQ = 5,10,15,20-tetrakis(3,5-di-tert-butylphenyl)quinoxalino[2,3-b]porphyrin and M = 2 H , Zn , Cu , Ni or Pd . The complexes all undergo two ring-centered reductions and one or two ring-centered oxidations in PhCN , CH 2 Cl 2, pyridine or THF . Additional redox reactions are also seen for the quinoxaline group in THF . The fusion of an electroactive quinoxaline group to the porphyrin macrocycle results in an 80 to 270 mV shift of E 1/2 towards easier reductions and the appearance of a third reduction which is assigned as a quinoxaline-centered redox process. The average HOMO-LUMO gap for the ( P ) M and ( PQ ) M derivatives is 2.26 ± 0.09 V and 2.14 ± 0.08 V , respectively. Both values are smaller than the average separation of 2.33 ± 0.13 V for the corresponding derivatives of tetraphenylporphyrin. The electrochemistry and UV-visible spectroelectrochemcal data indicate that moderate communication exists between the quinoxaline unit and the porphyrin π-ring system.

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Poddutoori, Premaladha, Prashanth Kumar Poddutoori et Bhaskar G. Maiya. « Nucleobase (A, T, G and C) appended tri-cationic water-soluble porphyrins : synthesis, characterization, binding and photocleavage studies with DNA ». Journal of Porphyrins and Phthalocyanines 10, n^o 01 (janvier 2006) : 1–12. http://dx.doi.org/10.1142/s1088424606000028.

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A series of nucleobase appended tri-cationic porphyrins ( AT 4, TT 4, GT 4 and CT 4) have been synthesized and their binding and cleaving ability of DNA were investigated in this present study. UV-vis, fluorescence, circular dichroism and thermal melting studies were carried out to investigate binding of the porphyrin with calf thymus DNA (CTDNA). The apparent binding constant ( K app ) and the intrinsic binding constant ( K b) values calculated from UV-vis and fluorescence titrations, respectively, were comparable to 5,10,15,20-tetra(N-methylpyridinium-4-yl) porphyrin ( H 2 T 4) or slightly more for few compounds. Circular dichroism spectra of these porphyrins with DNA show variation in their mode of binding. Among the nucleobase appended tri-cationic porphyrins, the porphyrin in GT4 and TT4 exhibit strong intercalating ability in the DNA duplex whereas the porphyrin in AT 4 and CT 4 exhibit very less ability for intercalation. The intercalating efficiency of the porphyrin in GT 4 is even stronger than that of the H 2 T 4. The steric strain exists between the tri-cationic porphyrin moiety and the DNA may decrease depending on (a) the ease to exhibit keto-enol tautomerism due to the more acidic protons in guanine and thymine, (b) extended conjugation and (c) hydrogen bonding capability of the nucleobase moieties. Photocleavage proclivities with pBR322 DNA in the presence of light reveal that AT 4, TT 4 and CT 4 show same amount of cleavage but GT 4 shows more cleaving efficiency than H 2 T 4 due to the stacked guanine moieties those are more reducing than a single guanine residue. The singlet oxygen mechanism that is responsible for the photocleavage was confirmed with various inhibitors and interestingly with Tiron (disodium salt of 1,2-dihydroxy-3,5-benzenedisulfonic acid) the photocleaving efficiency increases due to the inhibition of superoxide formation.

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Chae, Seung Hyun, Kicheon Yoo, Yo Sub Lee, Min Ju Cho, Jong Hak Kim, Min Jae Ko, Suk Joong Lee et Dong Hoon Choi. « Novel π-extended porphyrin derivatives for use in dye-sensitized solar cells ». Journal of Porphyrins and Phthalocyanines 18, n^o 07 (juillet 2014) : 569–78. http://dx.doi.org/10.1142/s1088424614500308.

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Two novel donor-π-acceptor (D-π-A type) porphyrin dyes were successfully synthesized and use in a dye-sensitized solar cell (DSSC). The molecular structures of both porphyrins are composed of the same dialkyl-substituted diphenylamino unit acting as the donor part, and two bisalkoxyphenyl substituents at the 5,15-meso positions. The acceptor part is composed of different ethyne-linked π-extended bridges, and a cyanoacrylic acid (Dye I) or carboxyphenyl (Dye II) moiety acting as anchoring groups. In order to investigate the effects of including the π-extended bridge between the porphyrin and acceptor unit, two different π-extended bridges such as 2,2′-bithiophene and 2-(phenylethynyl)-thiophene, were employed. In particular, Dye II contains two triple bonds between donor substituted porphyrin and carboxylic acid group. These modifications could potentially reduce dye aggregation on the TiO 2 surface. The charge recombination resistance and diffusion length for the cells with Dye II were relatively higher for all the measured ranges of bias potentials, implying that electron recombination loss from injected electrons was highly suppressed when Dye II molecules were adsorbed on the TiO 2 surface. Eventually, Dye II containing a 2,2′-bithiophene π-spacer and anchored trough a carboxyphenyl group exhibited a superior power conversion efficiency of 6.7% under AM 1.5 illumination (100 mW.cm-2) in a photoactive area of 0.46 cm2 than Dye I with a 2-(phenylethynyl)thiophene (PCE = 3.5%) anchored through a cyanoacrylic group.

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Thomas, Michael B., Siddhartha Kumar, Timothy Esquivel, Hong Wang et Francis D’Souza. « Excited state electron transfer in A2 and A2B2 functionalized zinc porphyrins carrying rigid and flexible β-pyrrole π-extended substituents ». Journal of Porphyrins and Phthalocyanines 24, n^o 05n07 (mai 2020) : 904–19. http://dx.doi.org/10.1142/s1088424620500017.

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Optical absorption and emission, electrochemical, and photochemical properties of peripherally functionalized with flexible and rigid [Formula: see text]-extended substituents on A2 and A2B2 type zinc porphyrins is investigated. The significance of rigid [Formula: see text]-substituents over flexible ones in governing the spectral properties is unraveled. Flexible [Formula: see text]-substituents on the porphyrin ring caused appreciable spectral broadening compared to porphyrin carrying rigid [Formula: see text]-substituents. Further, supramolecular dyads are formed by coordinating phenyl imidazole functionalized fullerene, C[Formula: see text]Im. The calculated binding constants for the 1:1 complexes is in the order of 2–7 × 105 M[Formula: see text] suggesting stable complex formation. Free-energy calculations performed according to the Rehm–Weller approach suggested possibility of excited state electron transfer in these dyads. Femtosecond transient absorption studies of the dyads performed in [Formula: see text]-dichlorobenzene showed evidence of occurrence of electron transfer from the singlet-excited state that was in competition with the intersystem crossing process to populate the triplet-excited state of porphyrins.

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Yaseen, Muhammad, Muhammad A. Rashid, Muhammad A. Iqbal, Zahid Farooq, Muhammad Idrees, Muhammad A. Qayyum, Azeem Intisar, Mian HR Mahmood, Ibrahim Khan et Muhammad Latif. « Synthesis, photoinduced amination and topological indices of novel porphyrin dyads ». Journal of Porphyrins and Phthalocyanines 24, n^o 08 (août 2020) : 1054–65. http://dx.doi.org/10.1142/s1088424620500200.

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Transition-metal-catalyzed homo and hetero coupling is a rapidly growing area of research. This work refers to the nickel-catalyzed photoinduced amination study of [Formula: see text]-bromotetraarylporphyrin and its Ni(II), Zn(II) and Cu(II) complexes. The selective mono [Formula: see text]-bromination of 5,10,15,20-tetrakis(4[Formula: see text]-isopropylphenyl)porphyrin was achieved with [Formula: see text]-bromosuccinimide. Under similar conditions, [Formula: see text]-bromination of Ni(II), Zn(II) and Cu(II) complexes of 5,10,15,20-tetrakis(4[Formula: see text]-isopropylphenyl)porphyrin successfully afforded the corresponding 2-bromometalloporphyrins. The [Formula: see text]-bromoporphyrin/metalloporphyrins were coupled with three different amines through the creation of the C–N bond by using an economical and air-tolerant photoactive catalyst (NiBr[Formula: see text] · 3H2O) at room temperature under 365 nm radiations. Nickel-catalyzed amination yields are compared with the traditional Buchwald–Hartwig amination yields. Due to the low operational cost, photoinduced nickel-catalyzed C–N couplings were found to be more economical than the Buchwald–Hartwig amination procedure, although the latter afforded higher yields. The nickel-catalyzed photoamination reaction was also extended for the one-pot synthesis of pyridine-3,5-diamine bridged porphyrin dyad. The intramolecular cyclization of the pyridine-3,5-diamine-bridged porphyrin dyad afforded a novel quinolino-fused porphyrin dyad. Degree- and distance-based topological indices of the newly synthesized porphyrins were calculated and correlated with their molar refractivity. All newly synthesized porphyrins are characterized by UV-vis, FTIR, 1H NMR, elemental analysis and mass spectrometry.

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Baytaeva, D. A., et S. S. Bessmeltsev. « The metabolitic role of the iron porphyrin complex in the development of anemic syndrome in patients with minor form of β-thalassemia ». Kazan medical journal 93, n^o 1 (15 février 2012) : 7–11. http://dx.doi.org/10.17816/kmj2135.

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Aim. To determine the significance of the main indicators of metabolism of porphyrins and markers of iron metabolism in the development of anemic syndrome during β-thalassemia minor. Methods. Examined were 58 patients with β-thalassemia minor with a concomitant deficiency of the enzyme glucose-6-phosphate dehydrogenase and 150 patients β-thalassemia minor without the concomitant enzymopathy. Hemoglobin electrophoresis was used to verify the diagnosis of β-thalassemia. Evaluated were the main indicators of porphyrin metabolism in the erythrocytes and urine in comparison with the reserve pool of iron in the blood serum, bone marrow and liver. Results. It has been shown that the assessment of soluble transferrin receptors and zinc protoporphyrin - is an alternative to assessing serum iron. Changes in the metabolism of iron is not the only cause of hypochromic microcytic anemia in patients with β-thalassemia minor. A large role is played by the fluctuations of the concentration of free forms of porphyrins in erythrocytes. With their help developed were differential diagnostic criteria, which distinguish the minor form from other forms of β-thalassemia and other iron deficiency states. During β-thalassemia minor, regardless of concomitant enzymopathy present was the instability of the main indicators of metabolism of the iron porphyrin complex. Conclusion. Extended evaluation of indicators of iron metabolism in conjunction with the assessment of precursors of porphyrin metabolism and free erythrocyte porphyrins is of high diagnostic value in determining the severity of anemia.

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Barbe, Jean-Michel, Fabien Burdet, Enrique Espinosa, Claude P. Gros et Roger Guilard. « New insights into the synthesis of porphyrin-corrole and biscorrole systems ». Journal of Porphyrins and Phthalocyanines 07, n^o 05 (mai 2003) : 365–74. http://dx.doi.org/10.1142/s1088424603000471.

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As in the case of porphyrins, the relatively easier synthesis of meso-substituted corroles compared to that of β-pyrrole substituted ones greatly limits the use of these latter derivatives. Here we show, for the synthesis of β-substituted biscorrole and porphyrin-corrole dyads, that a simple replacement of sodium hydrogen carbonate by sodium acetate in the final cyclisation step of the a,c-biladiene to the corrole ring, increases the yield by at least a factor of 3. This reaction can be extended to the synthesis of β-substituted monocorroles. Moreover, when cobalt acetate is added instead of the reoxidation step, a 34 to 63% yield in porphyrin-spacer- Co ( III ) corrole is obtained, thus avoiding isolation of the free-base and further metalation of this latter derivative. This “cyclisation-oxidation-metalation” reaction is of particular interest in the preparation of heterobimetallic species in porphyrin-corrole series. Indeed, it leads to the formation of the monocobalt derivative with the cobalt atom inside the corrole moiety allowing for the further insertion of a large variety of metals into the porphyrin macrocycle. Crystals of the monocobalt complex of a biphenylene bridged porphyrin-corrole derivative were obtained in the presence of pyridine and the structure was determined by X-ray diffraction analysis. The structure shows that only one pyridine molecule is bound to the cobalt centre in an exo position, thus indicating a strong steric hindrance from the porphyrin counterpart.

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Otieno, Sebastian, Anabel E. Lanterna, John Mack, Solomon Derese, Edith K. Amuhaya, Tebello Nyokong et Juan C. Scaiano. « Solar Driven Photocatalytic Activity of Porphyrin Sensitized TiO2 : Experimental and Computational Studies ». Molecules 26, n^o 11 (24 mai 2021) : 3131. http://dx.doi.org/10.3390/molecules26113131.

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The absence of a secure long-term sustainable energy supply is recognized as a major worldwide technological challenge. The generation of H2 through photocatalysis is an environmentally friendly alternative that can help solve the energy problem. Thus, the development of semiconductor materials that can absorb solar light is an attractive approach. TiO2 has a wide bandgap that suffers from no activity in the visible spectrum, limiting its use of solar radiation. In this research, the semiconductor absorption profile was extended into the visible region of the solar spectrum by preparing porphyrin-TiO2 (P-TiO2) composites of meso-tetra(4-bromophenyl)porphyrin (PP1) and meso-tetra(5-bromo-2-thienyl)porphyrin (PP2) and their In(III), Zn(II) and Ga(III) metal complexes. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed on the porphyrins to gain insight into their electron injection capability. The results demonstrate that P-TiO2 systems merit further in-depth study for applications that require efficient photocatalytic H2 generation.

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Elliott, Rory, Aoife A. Ryan, Aviral Aggarwal, Nianyong Zhu, Friedrich W. Steuber, Mathias O. Senge et Wolfgang Schmitt. « 2D Porphyrinic Metal-Organic Frameworks Featuring Rod-Shaped Secondary Building Units ». Molecules 26, n^o 10 (16 mai 2021) : 2955. http://dx.doi.org/10.3390/molecules26102955.

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Metal-organic frameworks (MOFs) encompass a rapidly expanding class of materials with diverse potential applications including gas storage, molecular separation, sensing and catalysis. So-called ‘rod MOFs’, which comprise infinitely extended 1D secondary building units (SBUs), represent an underexplored subclass of MOF. Further, porphyrins are considered privileged ligands for MOF synthesis due to their tunable redox and photophysical properties. In this study, the CuII complex of 5,15-bis(4-carboxyphenyl)-10,20-diphenylporphyrin (H2L-CuII, where H2 refers to the ligand’s carboxyl H atoms) is used to prepare two new 2D porphyrinic rod MOFs PROD-1 and PROD-2. Single-crystal X-ray analysis reveals that these frameworks feature 1D MnII- or CoII-based rod-like SBUs that are coordinated by labile solvent molecules and photoactive porphyrin moieties. Both materials were characterised using infrared (IR) spectroscopy, powder X-ray diffraction (PXRD) spectroscopy and thermogravimetric analysis (TGA). The structural attributes of PROD-1 and PROD-2 render them promising materials for future photocatalytic investigations.

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Mongwaketsi, Nametso, Noluthando Mayedwa, Nolubabalo Matinise, Kasinathan Kaviyarasu, Raymond Sparrow et Malik Maaza. « Polymer matrices for porphyrin nanorods incorporation. Artificial light harvesting applications ». Journal of Porphyrins and Phthalocyanines 22, n^o 04 (avril 2018) : 303–17. http://dx.doi.org/10.1142/s1088424618500268.

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This contribution is focused on the supramolecular approach in exploration of aggregates formation by two different porphyrins wherein self-assembly plays an important role. Spectroscopic and microscopic studies usually provide information on investigations regarding the effects of various parameters on the fabrication of porphyrin aggregates by ionic self- assembly. Various properties of ionic self-assembled porphyrin nanorods have been investigated, including nonlinear optical (NLO) properties, and these studies were influenced by the fact that porphyrins have great thermal stability and extended [Formula: see text]conjugated macro cyclic rings which give them large nonlinear optical effects. The major reasons limiting porphyrin nanorods photonic applications include the difficulty of handling them in liquid solutions and their degradation with long exposure to light. This necessitates the use of appropriate solid matrices to host the nanorods. Inspired by the precise organization and orientation of the chromophores in natural systems, attention has been on the design of nanometer sized chromophoric assemblies, which may find applications in the field of molecular photonics. However, it is challenging to design multicomponent systems with controlled structural arrangement at the molecular level. A lack of precise arrangement may have a negative impact on the construction of an efficient artificial light harvesting system. This review is focused on exploring the possibility of incorporating nanorods into polymer matrices to overcome the limiting factors of applications of these materials in photonic devices.

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Crossley, Maxwell J., Craig S. Sheehan, Tony Khoury, Jeffery R. Reimers et Paul J. Sintic. « Construction of building blocks for extended porphyrin arrays by nitration of porphyrin-2,3-diones and quinoxalino[2,3-b]porphyrins ». New J. Chem. 32, n^o 2 (2008) : 340–52. http://dx.doi.org/10.1039/b712643c.

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Matlachowski, Corinna, et Matthias Schwalbe. « Photochemical CO2-reduction catalyzed by mono- and dinuclear phenanthroline-extended tetramesityl porphyrin complexes ». Dalton Transactions 44, n^o 14 (2015) : 6480–89. http://dx.doi.org/10.1039/c4dt03846k.

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The conversion of CO₂ into CO is catalyzed by mono- and dinuclear phenanthroline-extended porphyrin complexes. The influence of the central metal center in the porphyrin cavity as well as of an attached ruthenium fragment at the phenanthroline moiety was investigated in wavelength-dependent photolysis experiments.

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Shiu, Jia-Wei, Yen-Cheng Chang, Chien-Yi Chan, Hui-Ping Wu, Hung-Yu Hsu, Chin-Li Wang, Ching-Yao Lin et Eric Wei-Guang Diau. « Panchromatic co-sensitization of porphyrin-sensitized solar cells to harvest near-infrared light beyond 900 nm ». Journal of Materials Chemistry A 3, n^o 4 (2015) : 1417–20. http://dx.doi.org/10.1039/c4ta06589a.

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We designed a dimeric porphyrin dye based on an efficient push–pull zinc porphyrin with extended π-conjugation so that the light-harvesting ability exhibits a panchromatic feature covering a broad spectral region from 400 nm to 900 nm.

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Nalaoh, Phattananawee, Sareeya Bureekaew, Vinich Promarak et Jonathan S. Lindsey. « Fourfold alkyl wrapping of a copper(II) porphyrin thwarts macrocycle π–π stacking in a compact supramolecular package ». Acta Crystallographica Section C Structural Chemistry 76, n^o 7 (5 juin 2020) : 647–54. http://dx.doi.org/10.1107/s2053229620007172.

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Porphyrins are valuable constituents in optoelectronic, catalytic, and other applications, yet control of intermolecular π–π stacking is invariably essential to attain the desired properties. Superstructures built onto the porphyrin, often via meso-aryl groups, can afford facial encumbrance that suppresses π–π stacking, although some molecular designs have provided insufficient facial coverage and many have entailed cumbersome syntheses. In this study, a copper(II) porphyrin bearing four meso substituents, namely, {10,20-bis[2,6-bis(octyloxy)phenyl]-5,15-dibromoporphinato}copper(II), [Cu(C64H82Br2N4O4)], was prepared by metalation of the corresponding free-base porphyrin and was characterized by single-crystal X-ray diffraction. The crystal structure reveals a dihedral angle of 111.1 (2)° for the plane of the meso-aryl group relative to the plane of the porphyrin, with both aryl groups tilted in the same direction. Each of the four octyloxy groups exhibits a gauche conformation for the –OCH2CH2– unit but is extended with four or five anti (–CH2CH2–/H) conformations thereafter, causing each octyl group to span the dimension of the macrocycle. In a global frame of reference where the two Br atoms define the north/south poles and the two aryl groups are at antipodes on the equator, two octyl groups of one aryl unit project over the northern hemisphere (covering pyrroles A and B), whereas those of the other aryl unit project over the southern hemisphere (covering pyrroles C and D). Together, the four octyl groups ensheath the two faces of the porphyrin in a self-wrapped assembly. The closest approach of the Cu atom to an octyl methylene C atom (position 6) is 3.5817 (18) Å, the mean separations of neighboring porphyrin planes are 8.059 (4) and 4.693 (8) Å along the a and c axes, respectively, and the center-to-center distances between the Cu atoms of neighboring porphyrins are 10.2725 (4), 12.2540 (6), and 12.7472 (6) Å along the a, b, and c axes, respectively. The Hirshfeld surface analysis and two-dimensional (2D) fingerprint plots provide information concerning contact interactions in the supramolecular assembly of the solid crystal.

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Satake, Akiharu, Toshimasa Sugimura et Yoshiaki Kobuke. « Coordination-induced sliding motion of a complementary porphyrin-phthalocyanine dimer : fluorescence-based molecular switch ». Journal of Porphyrins and Phthalocyanines 13, n^o 03 (mars 2009) : 326–35. http://dx.doi.org/10.1142/s1088424609000450.

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The reversible control of dual (or multiple) states of molecules and supramolecules has attracted much attention for molecular switch, sensor, memory, logic gate, and molecular machine applications. In this paper, a ligand-induced sliding system using a complementary porphyrin-phthalocyanine dimer accompanied by a large fluorescence change is described. An imidazole-appended porphyrinatozinc-phthalocyaninatomagnesium complex 5 was synthesized by the palladium-catalyzed coupling reaction of the corresponding porphyrin and phthalocyanine moieties. The imidazole group of 5 coordinated to the magnesium ion of another 5 was formed spontaneously and dominantly to give a stacked dimer 5ST in non-coordinating solvents, such as chloroform, even at submicromolar concentration (< 10-6 M). When an appropriate amount of dimethyl sulfoxide (DMSO) was added to the 5ST solution, the stacked dimer was transformed almost quantitatively into the extended dimer 5Ex. This transformation was monitored by UV-vis and fluorescence spectroscopies. In the UV-vis spectra, the porphyrin's Soret band is split characteristically because of excitonic coupling between the two closely located porphyrins in 5Ex. At the same time, the fluorescence intensity of 5Ex at 700 nm (ex. 414 nm) increased by a factor of 28 compared with that of 5ST. Removal of the DMSO molecules by extraction with water from the system regenerated 5ST almost completely from 5Ex, and the fluorescence was quenched again. The reversible system can be repeated by cycles of addition and removal of DMSO. The present system can be classified as a coordination-induced sliding system accompanied by a large fluorescence change, and may be applied as a fluorescence-based molecular switch.

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Hooper, Riley W., Angel Zhang, Dominik Koszelewski, Jan P. Lewtak, Beata Koszarna, Christopher J. Levy, Daniel T. Gryko et Martin J. Stillman. « Differential quenching of the angular momentum of the B and Q bands of a porphyrin as a result of extended ring π-conjugation ». Journal of Porphyrins and Phthalocyanines 22, n^o 12 (décembre 2018) : 1111–28. http://dx.doi.org/10.1142/s1088424618501110.

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A novel porphyrin, whose [Formula: see text]-system has been extended via the presence of two additional carbon–carbon triple bonds on opposite meso-positions and by fusion of a single naphthalene unit simultaneously bridging the third meso-position and the [Formula: see text]-carbon of one of the pyrroles, has been synthesized in good yield. Absorption, magnetic circular dichroism, emission, and theoretical spectra are reported for the fused and unfused trans-naphthalene free base and zinc porphyrins. The fusing of one of the naphthalene moieties results in significant changes to the absorption spectrum and, very unusually, the bridged meso-[Formula: see text]-pyrrole fusion results in quenching of the MCD Faraday pseudo-A term in the porphyrin’s B band (S2). This unique effect was interpreted as resulting from the origin of the electronic structure of the second excited state (the B state). The [Formula: see text] and [Formula: see text] polarizations are completely mixed by the electronic effects of the non-symmetric extended conjugation of the [Formula: see text] ring. Analysis of the origin of the MCD signal indicates that the presence of this novel mixed polarization leads to negligible angular momentum in the important B state. To our knowledge, this is the first report in which the magnetic moment in a porphyrin’s intensely absorbing B band has been quenched while the angular momentum in the Q band, the first excited state, remains as normal. This implies that the photophysical properties of the B state are likely very different than those of the Q state, which has novel and significant implications for applications, especially in non-linear spectroscopy.

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Gonzalez, Monica C., et Alan C. Weedon. « Preparation and properties of a linked porphyrin–cyclodextrin ». Canadian Journal of Chemistry 63, n^o 3 (1 mars 1985) : 602–8. http://dx.doi.org/10.1139/v85-099.

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The synthesis of the linked porphyrin–cyclodextrin 3 and its zinc complex 4 is described and their characterization by 1H nmr, l3C nmr, circular dichroism, ultraviolet, and infrared spectroscopy is reported. The linked porphyrin–cyclodextrin compounds exhibited perturbed electronic absorption and emission spectra which are consistent with their adopting two conformations, one extended with little interaction between the porphyrin and cyclodextrin, and the other folded with the cyclodextrin weakly complexed to the porphyrin. Quenching of the porphyrin excited state of 3 by benzoquinone was examined by measurement of the fluorescence lifetime as a function of quinone concentration; the results suggest that the porphyrin excited state can be quenched intermolecularly by benzoquinone and also intramolecularly by quinone complexed within the cyclodextrin cavity.

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Pijeat, Joffrey, Milos Baljozovic, Raphael Lamare, Karl-Heinz Ernst et Stephane Campidelli. « On-Surface Synthesis of Fused Anthracenyl Porphyrin Derivatives ». ECS Meeting Abstracts MA2022-01, n^o 14 (7 juillet 2022) : 968. http://dx.doi.org/10.1149/ma2022-0114968mtgabs.

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For the last fifteen years, on-surface synthesis became an extremely popular and powerful method to fabricate nanostructures which otherwise would not have been accessible by conventional wet organic syntheses. The syntheses, realized in the chamber of high vacuum scanning tunneling microscope (STM), permitted the fabrication and the characterization of atomically defined nanostructures such as polycyclic aromatic hydrocarbons (PAH), graphene nanoribbons or 2D covalent networks.1 Among the organic molecules studied by STM, porphyrins are of particular importance because of their electronic and optical properties. Initial studies were mainly devoted to the supramolecular organization of porphyrins and porphyrin derivatives on surface and it is only in 2004 that noble metal surfaces were used as catalytic surface to perform reactions on the porphyrin cores.2 Since then, examples of open-shell porphyrin derivatives3 and conjugated oligomers4 were reported. While the synthesis of fused bis- and tetra-4,5-bis-(2,4,6-trimethylphenoxy)anthracen-9-yl porphyrins containing Ni(II) was reported by Anderson about 10 years ago,5 the formation π-extended porphyrin bearing unsubstituted anthracenyl moieties were never achieved. The formation of such compounds became possible by on-surface synthesis. Herein, we report on the synthesis of fused bis- and tetra-anthracenylporphyrin derivatives via the cyclodehydrogenation the parent meso-substituted molecules on a catalytic Au(111) surface.6 Depending on the annealing temperature, anthracenylporphyrins with the four anthracene fully linked to the porphyrin core or over-oxidized porphyrin in which the anthracene are connected two by two in 2-2’ position were observed by STM (Figure 1). Figure 1. STM images of the fused tetra-anthracenylporphyrins and related porphyrin structures References Clair, S.; de Oteyza, D. G. Chem. Rev. 2019, 119, 4717-4776. Fox, S.; Boyle, R. W. Chem. Commun. 2004, 1322-1323. a) Sun, Q.; Mateo, L. M.; Robles, R.; Ruffieux, P.; Lorente, N.; Bottari, G.; Torres, T.; Fasel, R. J. Am. Chem. Soc. 2020, 142, 18109-18117; b) Zhao, Y.; Jiang, K.; Li, C.; Liu, Y.; Xu, C.; Zheng, W.; Guan, D.; Li, Y.; Zheng, H.; Liu, C.; Luo, W.; Jia, J.; Zhuang, X.; Wang, S. J. Am. Chem. Soc. 2020, 142, 18532-18540. a) Mateo, L. M.; Sun, Q.; Liu, S.-X.; Bergkamp, J. J.; Eimre, K.; Pignedoli, C. A.; Ruffieux, P.; Decurtins, S.; Bottari, G.; Fasel, R.; Torres, T. Angew. Chem., Int. Ed. 2020, 59, 1334-1339; b) Mateo, L. M.; Sun, Q.; Eimre, K.; Pignedoli, C. A.; Torres, T.; Fasel, R.; Bottari, G. Chem. Sci. 2021, 12, 247-252. a) Davis, N. K. S.; Thompson, A. L.; Anderson, H. L. Org. Lett. 2010, 12, 2124-2127; b) Davis, N. K. S.; Thompson, A. L.; Anderson, H. L. J. Am. Chem. Soc. 2011, 133, 30-31. Baljozović, M. et al., in preparation Figure 1

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Chumakov, Denis, Anna Moiseeva, Alexander Anisimov, Boris Uzhinov et Andrey Khoroshutin. « Regioselective bromination of palladium tetraphenyltetrabenzoporphyrin to benzo-rings : Synthesis of mono- and octabromotetrabenzoporphyrins and their properties ». Journal of Porphyrins and Phthalocyanines 14, n^o 09 (septembre 2010) : 815–24. http://dx.doi.org/10.1142/s1088424610002653.

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Bromination of palladium meso-tetraphenyl tetrabenzoporphyrin ( Pd Ph4TBP, 1) by Me4NBr3 or Me4NBr/Br2 was shown to proceed regioselectively to the benzo-rings annelated to main porphyrin macrocycle. Conditions for preferential mono- and octa-bromination have been established. The respective mono- and octa-bromide ( Pd Ph4TBP( Br ), 2 and Pd Ph4TBP( Br )8, 3) have been isolated and characterized by UV-vis, NMR and LDI-TOF spectroscopy. Changes of electrochemical properties of tetrabenzoporphyrins induced by Br atoms were found to follow the same trends as the changes in analogous non-extended porphyrins. Room temperature phosphorescence is not substantially influenced by the substitution.

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Thomas, James O., Jakub K. Sowa, Bart Limburg, Xinya Bian, Charalambos Evangeli, Jacob L. Swett, Sumit Tewari et al. « Charge transport through extended molecular wires with strongly correlated electrons ». Chemical Science 12, n^o 33 (2021) : 11121–29. http://dx.doi.org/10.1039/d1sc03050g.

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Takagi, Shigeru, Yoshio Kato, Hiroyuki Furuta, Satoru Onaka et T. Ken Miyamoto. « Metal-metal bonds extended over a porphyrin ring ». Journal of Organometallic Chemistry 429, n^o 3 (mai 1992) : 287–99. http://dx.doi.org/10.1016/0022-328x(92)83180-p.

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Rubio-Magnieto, Jenifer, Florent Di Meo, Mamadou Lo, Cécile Delcourt, Sébastien Clément, Patrick Norman, Sébastien Richeter, Mathieu Linares et Mathieu Surin. « Binding modes of a core-extended metalloporphyrin to human telomeric DNA G-quadruplexes ». Organic & ; Biomolecular Chemistry 13, n^o 8 (2015) : 2453–63. http://dx.doi.org/10.1039/c4ob02097a.

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Epuran, Camelia, Ion Fratilescu, Ana-Maria Macsim, Anca Lascu, Catalin Ianasi, Mihaela Birdeanu et Eugenia Fagadar-Cosma. « Excellent Cooperation between Carboxyl-Substituted Porphyrins, k-Carrageenan and AuNPs for Extended Application in CO2 Capture and Manganese Ion Detection ». Chemosensors 10, n^o 4 (1 avril 2022) : 133. http://dx.doi.org/10.3390/chemosensors10040133.

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Significant tasks of the presented research are the development of multifunctional materials capable both to detect/capture carbon dioxide and to monitor toxic metal ions from waters, thus contributing to maintaining a sustainable and clean environment. The purpose of this work was to synthesize, characterize (NMR, FT-IR, UV-Vis, Fluorescence, AFM) and exploit the optical and emission properties of a carboxyl-substituted A3B porphyrin, 5-(4-carboxy-phenyl)-10,15,20-tris-(4-methyl-phenyl)–porphyrin, and based on it, to develop novel composite material able to adsorb carbon dioxide. This porphyrin-k-carrageenan composite material can capture CO2 in ambient conditions with a performance of 6.97 mmol/1 g adsorbent. Another aim of our research was to extend this porphyrin- k-carrageenan material’s functionality toward Mn2+ detection from polluted waters and from medical samples, relying on its synergistic partnership with gold nanoparticles (AuNPs). The plasmonic porphyrin-k-carrageenan-AuNPs material detected Mn2+ in the range of concentration of 4.56 × 10−5 M to 9.39 × 10−5 M (5–11 mg/L), which can be useful for monitoring health of humans exposed to polluted water sources or those who ingested high dietary manganese.

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Filatov, Mikhail A., Ernesta Heinrich, Katharina Landfester et Stanislav Baluschev. « meso-Tetraphenylporphyrin with a pi-system extended by fusion with anthraquinone ». Organic & ; Biomolecular Chemistry 13, n^o 25 (2015) : 6977–83. http://dx.doi.org/10.1039/c5ob00884k.

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Fusion of a porphyrin with anthraquinone through the synthesis of a suitably substituted pyrrole that can be cyclotetramerized and the optical properties of the resulting molecular system are described.

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Zurita, Adrián, Anna Duran, Josep M. Ribó, Zoubir El-Hachemi et Joaquim Crusats. « Hyperporphyrin effects extended into a J-aggregate supramolecular structure in water ». RSC Advances 7, n^o 6 (2017) : 3353–57. http://dx.doi.org/10.1039/c6ra27441b.

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Satrialdi, Reina Munechika, Vasudevanpillai Biju, Yuta Takano, Hideyoshi Harashima et Yuma Yamada. « The optimization of cancer photodynamic therapy by utilization of a pi-extended porphyrin-type photosensitizer in combination with MITO-Porter ». Chemical Communications 56, n^o 7 (2020) : 1145–48. http://dx.doi.org/10.1039/c9cc08563g.

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Lee, Chang Yeon, Chunxing She, Nak Cheon Jeong et Joseph T. Hupp. « Porphyrin sensitized solar cells : TiO2 sensitization with a π-extended porphyrin possessing two anchoring groups ». Chemical Communications 46, n^o 33 (2010) : 6090. http://dx.doi.org/10.1039/c0cc00257g.

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Sarabando, Sofia N., Cristina J. Dias, Cátia Vieira, Maria Bartolomeu, Maria G. P. M. S. Neves, Adelaide Almeida, Carlos J. P. Monteiro et Maria Amparo F. Faustino. « Sulfonamide Porphyrins as Potent Photosensitizers against Multidrug-Resistant Staphylococcus aureus (MRSA) : The Role of Co-Adjuvants ». Molecules 28, n^o 5 (22 février 2023) : 2067. http://dx.doi.org/10.3390/molecules28052067.

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Sulfonamides are a conventional class of antibiotics that are well-suited to combat infections. However, their overuse leads to antimicrobial resistance. Porphyrins and analogs have demonstrated excellent photosensitizing properties and have been used as antimicrobial agents to photoinactivate microorganisms, including multiresistant Staphylococcus aureus (MRSA) strains. It is well recognized that the combination of different therapeutic agents might improve the biological outcome. In this present work, a novel meso-arylporphyrin and its Zn(II) complex functionalized with sulfonamide groups were synthesized and characterized and the antibacterial activity towards MRSA with and without the presence of the adjuvant KI was evaluated. For comparison, the studies were also extended to the corresponding sulfonated porphyrin TPP(SO3H)4. Photodynamic studies revealed that all porphyrin derivatives were effective in photoinactivating MRSA (>99.9% of reduction) at a concentration of 5.0 μM upon white light radiation with an irradiance of 25 mW cm−2 and a total light dose of 15 J cm−2. The combination of the porphyrin photosensitizers with the co-adjuvant KI during the photodynamic treatment proved to be very promising allowing a significant reduction in the treatment time and photosensitizer concentration by six times and at least five times, respectively. The combined effect observed for TPP(SO2NHEt)4 and ZnTPP(SO2NHEt)4 with KI seems to be due to the formation of reactive iodine radicals. In the photodynamic studies with TPP(SO3H)4 plus KI, the cooperative action was mainly due to the formation of free iodine (I2).

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Ventura, Barbara, Fabien Durola, Julien Frey, Valérie Heitz, Jean-Pierre Sauvage et Lucia Flamigni. « Near-infrared dual luminescence from an extended zinc porphyrin ». Chem. Commun. 48, n^o 7 (2012) : 1021–23. http://dx.doi.org/10.1039/c1cc16739a.

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Finikova, Olga S., Andrei V. Cheprakov, Patrick J. Carroll, Sergio Dalosto et Sergei A. Vinogradov. « Influence of Nonplanarity and Extended Conjugation on Porphyrin Basicity ». Inorganic Chemistry 41, n^o 26 (décembre 2002) : 6944–46. http://dx.doi.org/10.1021/ic0260522.

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Pasternack, Robert F., Cavan Fleming, Stephanie Herring, Peter J. Collings, Julio dePaula, Gerard DeCastro et Esther J. Gibbs. « Aggregation Kinetics of Extended Porphyrin and Cyanine Dye Assemblies ». Biophysical Journal 79, n^o 1 (juillet 2000) : 550–60. http://dx.doi.org/10.1016/s0006-3495(00)76316-8.

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Bossa, Mario, Elena Cervone, Carmine Garzillo et Giuseppe Del Re. « On the electronic states of the extended porphyrin family ». Journal of Molecular Structure : THEOCHEM 342 (octobre 1995) : 73–86. http://dx.doi.org/10.1016/0166-1280(95)90087-x.

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Feixas, Ferran, Miquel Solà et Marcel Swart. « Chemical bonding and aromaticity in metalloporphyrins »,. Canadian Journal of Chemistry 87, n^o 7 (juillet 2009) : 1063–73. http://dx.doi.org/10.1139/v09-037.

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We report here the chemical bonding and aromaticity patterns in metalloporphyrins, which were obtained with density functional theory (DFT) calculations at the OPBE/TZP level. This level of theory was previously shown to be very accurate for determining spin-state splittings [J. Chem. Theory Comput. 2008, 4, 2057] of transition-metal complexes. We considered metalloporphyrins along the first-row transition metals (Sc–Zn) extended with alkaline-earth metals (Mg, Ca) and several second-row transition metals (Ru, Pd, Ag, Cd). An energy decomposition analysis was performed to study the metal–ligand interactions, which showed that almost all complexes are significantly stabilized through (covalent) orbital interactions. The only exception is with calcium as the central metal, which interacts with the porphyrin mainly through electrostatic interactions. Furthermore, we studied aromaticity patterns for these complexes by looking at a number of (structural and electronic) aromaticity descriptors, for both the inner-ring and outer-ring of the porphyrin and of the pyrroles. The inner-ring (N16) aromaticity is shown to be unaffected by metal complexation, while the outer-ring (N20) and the pyrrole (N5) aromaticities are found to increase significantly in the metal coordinated porphyrins.

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Krishna, Jonnadula Venkata Suman, Devulapally Koteshwar, Towhid H. Chowdhury, Surya Prakash Singh, Idriss Bedja, Ashraful Islam et Lingamallu Giribabu. « Efficient near IR porphyrins containing a triphenylamine-substituted anthryl donating group for dye sensitized solar cells ». Journal of Materials Chemistry C 7, n^o 43 (2019) : 13594–605. http://dx.doi.org/10.1039/c9tc03943k.

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Alam, Md M., F. Bolze, C. Daniel, L. Flamigni, C. Gourlaouen, V. Heitz, S. Jenni, J. Schmitt, A. Sour et B. Ventura. « π-Extended diketopyrrolopyrrole–porphyrin arrays : one- and two-photon photophysical investigations and theoretical studies ». Physical Chemistry Chemical Physics 18, n^o 31 (2016) : 21954–65. http://dx.doi.org/10.1039/c6cp01844k.

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Takano, Yuta, Kazuaki Miyake, Jeladhara Sobhanan, Vasudevanpillai Biju, Nikolai V. Tkachenko et Hiroshi Imahori. « Near-infrared light control of membrane potential by an electron donor–acceptor linked molecule ». Chemical Communications 56, n^o 83 (2020) : 12562–65. http://dx.doi.org/10.1039/d0cc05326k.

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(π-Extended porphyrin)–fullerene linked molecules are synthesized to utilize the molecular excited states induced by near-infrared light. One of the molecules successfully alters the membrane potential.

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Koner, Rajesh, et Israel Goldberg. « Square-grid coordination networks of (5,10,15,20-tetra-4-pyridylporphyrinato)zinc(II) in its clathrate with two guest molecules of 1,2-dichlorobenzene : supramolecular isomerism of the porphyrin self-assembly ». Acta Crystallographica Section C Crystal Structure Communications 65, n^o 3 (25 février 2009) : m139—m142. http://dx.doi.org/10.1107/s0108270109005691.

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The title compound, (5,10,15,20-tetra-4-pyridylporphyrinato)zinc(II) 1,2-dichlorobenzene disolvate, [Zn(C40H24N8)]·2C6H4Cl2, contains a clathrate-type structure. It is composed of two-dimensional square-grid coordination networks of the self-assembled porphyrin moiety, which are stacked one on top of the other in a parallel manner. The interporphyrin cavities of the overlapping networks combine into channel voids accommodated by the dichlorobenzene solvent. Molecules of the porphyrin complex are located on crystallographic inversion centres. The observed two-dimensional assembly mode of the porphyrin units represents a supramolecular isomer of the unique three-dimensional coordination frameworks of the same porphyrin building block observed earlier. The significance of this study lies in the discovery of an additional supramolecular isomer of the rarely observed structures of metalloporphyrins self-assembled directly into extended coordination polymers without the use of external ligand or metal ion auxiliaries.

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Diskin-Posner, Yael, et Israel Goldberg. « Porphyrin sieves. Designing open networks of tetra(carboxyphenyl)porphyrins by extended coordination through sodium ion auxiliaries ». New Journal of Chemistry 25, n^o 7 (2001) : 899–904. http://dx.doi.org/10.1039/b100580b.

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Babu, Balaji, John Mack et Tebello Nyokong. « A heavy-atom-free π-extended N-confused porphyrin as a photosensitizer for photodynamic therapy ». New Journal of Chemistry 45, n^o 12 (2021) : 5654–58. http://dx.doi.org/10.1039/d1nj00112d.

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Crossley, Maxwell J., Linda J. Govenlock et Jognandan K. Prashar. « Synthesis of porphyrin-2,3,12,13- and -2,3,7,8-tetraones : building blocks for the synthesis of extended porphyrin arrays ». Journal of the Chemical Society, Chemical Communications, n^o 23 (1995) : 2379. http://dx.doi.org/10.1039/c39950002379.

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