1159-86-0Relevant articles and documents
Impact of photosensitizer orientation on the distance dependent photocatalytic activity in zinc phthalocyanine-nanoporous gold hybrid systems
Epp, Alexander,Klangnog, Khaetthariya,Kohr?de, Mathis,Schnurpfeil, Günter,Steinebrunner, David,Tapia Burgos, Jorge Adrian,W?hrle, Dieter,Wichmann, Andre,Wittstock, Arne
, p. 23203 - 23211 (2020)
Nanoporous gold powder was functionalized in a two-step approach by an azide terminated alkanethiol self-assembled monolayer (SAM) and a zinc(ii) phthalocyanine (ZnPc) derivative by copper catalyzed azide-alkyne cycloaddition (CuAAC). A series of different hybrid systems with systematic variation of the alkyl chain length on both positions, the alkanethiol SAM and the peripheral substituents of the ZnPc derivative, was prepared and studied in the photooxidation of diphenylisobenzofuran (DPBF). An enhancement by nearly one order of magnitude was observed for the photosensitized singlet oxygen (1O2) generation of the hybrid systems compared to the same amount of ZnPc in solution caused by the interaction of the npAu surface plasmon resonance and the excited state of the immobilized sensitizer. This interaction was shown to be distance dependent, with decreasing activity for short SAMs with alkyl chain lengths 8 methylene groups due to decreasing energy transfer for long distances. An unexpected distance dependent behaviour was observed for the variation of the peripheral alkyl chain on the photosensitizer revealing a planar orientation of the immobilized photosensitizer on the nanoporous gold surface by a penta-coordinated central zinc ion through interaction with free azide groups from the self-assembled monolayer.
Synthesis and application of near-infrared absorbing morpholino-containing aza-BODIPYs
Jiang, Xin-Dong,Jia, Lei,Su,Li, Chen,Sun, Changliang,Xiao, Linjiu
, p. 4556 - 4560 (2019)
Morpholino-containing aza-BODIPYs at 3,5-positions were synthesized. The maxima absorption and emission of these dyes locate at the near-infrared region. Aza-BODIPY 1 with the morpholino group as a pH-sensitive functionality could be used to be a pH probe, and the dramatic increase in fluorescence intensity at 675 nm by about 1500 folds. Moreover, the singlet oxygen generation of PS 2 with the dibromo groups at 2,6-positions was more effective than that of the parent dye 1.
OXIDATION OF DIENES BY TRIPHENYLPHOSPHINE PEROXOPALLADIUM
Dagonneau, M.,Fauvarque, J. F.
, p. 113 - 118 (1983)
Thermal reaction of 1,3-diphenylisobenzofuran and tetramethylcyclopentadienone with PdLO2 complex (L = PPh3) gives compounds identical to those produced by singlet molecular oxygen.Photochemical reaction of 1,9-diphenylanthracene with PdLO2 or PdL3 in the presence of oxygen gives the 9,10-endoperoxide adduct.
A new protocol for the synthesis of new thioaryl-porphyrins derived from 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin: Photophysical evaluation and DNA-binding interactive studies
Foletto, Patrícia,Correa, Fabiula,Dornelles, Luciano,Iglesias, Bernardo A.,Da Silveira, Carolina H.,Nogara, Pablo A.,Da Rocha, Jo?o B. T.,Faustino, Maria A. F.,Rodrigues, Oscar E. D.
, (2018)
A new protocol for the preparation of thioaryl-porphyrins is described. The compounds were prepared from different disulfides employing NaBH4 as a reducing agent. The methodology allowed the preparation of four different thioaryl-porphyrins in very-good to excellent yields under soft conditions, such as short reaction times and smooth heating. Additionally, the photophysical properties of new compounds were determined and experimental and theoretical DNA interactions were assessed.
Titanium-Carboxylate Metal-Organic Framework Based on an Unprecedented Ti-Oxo Chain Cluster
Keum, Yesub,Park, Seonghun,Chen, Ying-Pin,Park, Jinhee
, p. 14852 - 14856 (2018)
Titanium(IV)-based metal-organic frameworks (Ti-MOFs) have received significant attention in recent years due to their numerous photocatalytic applications. We herein prepare the single-crystalline Ti-carboxylate MOF (DGIST-1) composed of an unprecedented Ti-oxo chain cluster and the porphyrinic ligand, TCPP (tetrakis(4-carboxyphenyl)porphyrin). Preformed Ti-oxo clusters were used as Ti4+ sources to avoid the spontaneous hydrolysis and condensation reactions of traditional Ti-alkoxide precursors, thus, enabling the formation of the highly crystalline Ti-MOF. The successfully activated DGIST-1 exhibited a higher surface area (i.e., 1957.3 m2 g?1) than previously reported Ti-MOFs due to its high crystallinity. Furthermore, the visible-light-responsive photocatalytic activity of DGIST-1 was confirmed by the simultaneous generation of singlet oxygen (1O2) and superoxide (.O2?) species, in addition to the highly efficient and selective oxidation of benzyl alcohol to benzaldehyde.
The photochemistry of o-benzylbenzophenone: A pericyclic cornucopia
Sobczak, Martin,Wagner, Peter J.
, p. 2523 - 2526 (1998)
UV irradiation of the title compound produces cis-1,2- diphenylbenzocyclobutenol quantitatively. While stable at temperatures below 0°, at room temperature it establishes a high enough equilibrium population of its EE o-xylylenol precursor to undergo slow reversion to ketone and rapid reaction with maleic anhydride or oxygen, as well as photoinduced cyclization to the trans cyclobutenol.
N,N′-bicarbazole-benzothiadiazole-based conjugated porous organic polymer for reactive oxygen species generation in live cells
Behera, Biswajit,Giri, Arkaprabha,Kundu, Subhankar,Patra, Abhijit,Saha, Nitu
, p. 6875 - 6878 (2021)
A π-conjugated porous organic polymer (BCzBz) was fabricated employingN,N′-bicarbazole and benzothiadiazole as molecular building units exhibiting broad visible light absorption. The photostable, water-dispersible, and cytocompatible BCzBz was demonstrated as an efficient probe for intracellular reactive oxygen species generation under photoirradiation.
Self-Assembled PtII8Metallosupramolecular Tubular Cage as Dual Warhead Antibacterial Agent in Water
Bhattacharyya, Soumalya,De, Mrinmoy,Mukherjee, Partha Sarathi,Sahoo, Jagabandhu,Venkateswarulu, Mangili,Zangrando, Ennio
, p. 12690 - 12699 (2020)
Development of photosensitizer-based self-assembled metallosupramolecular architectures with important applications is an emerging trend in supramolecular chemistry. In this study, we report a new benzothiadiazole-based tetra-pyridyl ligand (L), which upon self-assembly with a cis-block 90° Pt(II) acceptor generated an unprecedented tetrafacial Pt(II)8 photoactive tubular molecular cage (PMB1). This cage could bring an extraordinary photosensitizer, benzothiadiazole, into water which is otherwise insoluble. PMB1 is fluorescent and shows photogeneration of singlet oxygen in an aqueous medium. These features make PMB1 a potent antimicrobial agent in water in both the presence and absence of light. In comparison to its building blocks and water-soluble alkylated charged ligand ([LMe4][4NO3]), the cage shows much enhanced photoinduced antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) as a representative of Gram-positive bacteria and Pseudomonas aeruginosa (PA) as a representative of Gram-negative bacteria. PMB1 is successful at inactivating the bacterial growth via both photoactivation of molecular oxygen and membrane depolarization mechanisms, thus proving to be a dual warhead. Inactivation of bacteria in water using such a supramolecular architecture is noteworthy and can shed light on the generation of new antimicrobial supramolecular systems.
Kinetic and mechanistic aspects of solid state, nanostructured porphyrin diacid photosensitizers in photooxidation of sulfides
Nasrollahi, Rahele,Heydari-Turkmani, Akram,Zakavi, Saeed
, p. 1260 - 1272 (2019)
In continuation of our studies on the photocatalytic performance of porphyrin diacids, the kinetics and mechanisms of the photooxidation of para-substituted phenyl methyl sulfides (para X = H, CH3, OCH3, Cl, and F) catalyzed by a series of meso-tetra(aryl)porphyrins (aryl = phenyl, 2-chlorophenyl, 2-methylphenyl, 4-chlorophenyl, 4-methylphenyl and 4-methoxyphenyl) immobilized on Amberlyst 15 nanostructures (nanoAmb), H2T(2 or 4-X)PP@nanoAmb, are reported. The immobilization of porphyrins on the polymer was confirmed by diffuse reflectance UV-vis spectroscopy and EDX analysis. While little or no catalyst degradation was observed for a reaction time of ca. 3 h, the electron-deficient porphyrins (pseudo-first-order rate constants, kobs = 0.0049-0.012 min-1) showed faster second-order kinetics than the electron-rich ones (kobs = 2.30 × 10-5-9.92 × 10-4 min-1). The order of photocatalytic activity of the porphyrins approximately correlates with the singlet oxygen quantum yield (φΔ) of the photosensitizers. Diffuse reflectance UV-vis spectra of the immobilized porphyrins demonstrated a large red shift of the Soret and Q bands of the porphyrins which was more dominant in the case of H2T(4-OMe)PP. The weak overlap between the emission spectrum of the light source and the absorption spectrum of the latter was used to explain the low photocatalytic activity of H2T(4-OMe)PP@nanoAmb. The observation of a slope (ρ) of -2.80 for the oxidation of methyl phenyl sulfide and para-substituted phenyl methyl sulfides is in accord with the involvement of an electrophilic oxidation mechanism mediated by singlet oxygen species. H2TPP@naoAmb was recovered and reused at least five times without significant loss of the catalytic activity and detectable catalyst degradation, giving a turnover number of 5 × 5000 for five successive reactions. The catalyst was successfully used for large-scale (up to 6.6 mmol of sulfide per batch, in a 1:10000 catalyst-to-sulfide molar ratio) photooxidation of a wide range of sulfides to the corresponding sulfoxide in a water/acetonitrile solvent mixture.
Investigation on Optical and Biological Properties of 2-(4-Dimethylaminophenyl)benzothiazole Based Cycloplatinated Complexes
Lara, Rebeca,Millán, Gonzalo,Moreno, M. Teresa,Lalinde, Elena,Alfaro-Arnedo, Elvira,López, Icíar P.,Larráyoz, Ignacio M.,Pichel, José G.
, p. 15757 - 15772 (2021)
The optical and biological properties of 2-(4-dimethylaminophenyl)benzothiazole cycloplatinated complexes featuring bioactive ligands ([{Pt(Me2N-pbt)(C6F5)}L] [L=Me2N-pbtH 1, p-dpbH (4-(diphenylphosphino)benzoic acid) 2, o-dpbH (2-(diphenylphosphino)benzoic acid) 3), [Pt(Me2N-pbt)(o-dpb)] 4, [{Pt(Me2N-pbt)(C6F5)}2(μ-PRnP)] [PR4P=O(CH2CH2OC(O)C6H4PPh2)2 5, PR12P=O{(CH2CH2O)3C(O)C6H4PPh2}2 6] are presented. Complexes 1–6 display 1ILCT and metal-perturbed 3ILCT dual emissions. The ratio between both bands is excitation dependent, accomplishing warm-white emissions for 2, 5 and 6. The phosphorescent emission is lost in aerated solutions owing to photoinduced electron transfer to 3O2 and the formation of 1O2, as confirmed in complexes 2 and 4. They also exhibit photoinduced phosphorescence enhancement in non-degassed DMSO due to local oxidation of DMSO by sensitized 1O2, which causes a local degassing. Me2N-pbtH and the complexes specifically accumulate in the Golgi apparatus, although only 2, 3 and 6 were active against A549 and HeLa cancer cell lines, 6 being highly selective in respect to nontumoral cells. The potential photodynamic property of these complexes was demonstrated with complex 4.
