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Lancel M, Lindgren M, Monnereau C, Amara Z. Kinetic effects in singlet oxygen mediated oxidations by immobilized photosensitizers on silica. Photochem Photobiol Sci 2024; 23:79-92. [PMID: 38066378 DOI: 10.1007/s43630-023-00502-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/04/2023] [Indexed: 02/02/2024]
Abstract
Singlet oxygen (1O2) mediated photo-oxidations are important reactions involved in numerous processes in chemical and biological sciences. While most of the current research works have aimed at improving the efficiencies of these transformations either by increasing 1O2 quantum yields or by enhancing its lifetime, we establish herein that immobilization of a molecular photosensitizer onto silica surfaces affords significant, substrate dependant, enhancement in the reactivity of 1O2. Probing a classical model reaction (oxidation of Anthracene-9, 10-dipropionic acid, ADPA or dimethylanthracene, DMA) with various spectrofluorimetric techniques, it is here proposed that an interaction between polar substrates and the silica surface is responsible for the observed phenomenon. This discovery could have a direct impact on the design of future photosensitized 1O2 processes in various applications ranging from organic photochemistry to photobiology.
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Affiliation(s)
- Maxime Lancel
- Equipe Chimie Moléculaire, Laboratoire de Génomique, Bioinformatique et Chimie Moléculaire, (GBCM), EA 7528, Conservatoire national des arts et metiers, HESAM université, 75003, Paris, France
| | - Mikaël Lindgren
- Faculty of Natural Sciences, Department of Physics, Norwegian University of Science and Technology, Gløshaugen, 7491, Trondheim, Norway
| | - Cyrille Monnereau
- ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, University of Lyon, 69364, Lyon, France.
| | - Zacharias Amara
- Equipe Chimie Moléculaire, Laboratoire de Génomique, Bioinformatique et Chimie Moléculaire, (GBCM), EA 7528, Conservatoire national des arts et metiers, HESAM université, 75003, Paris, France.
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2
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Heterogeneous Photoredox Catalysis Based on Silica Mesoporous Material and Eosin Y: Impact of Material Support on Selectivity of Radical Cyclization. MOLECULES (BASEL, SWITZERLAND) 2023; 28:molecules28020549. [PMID: 36677607 PMCID: PMC9865568 DOI: 10.3390/molecules28020549] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/16/2022] [Accepted: 12/23/2022] [Indexed: 01/09/2023]
Abstract
Heterogenization of the photocatalyst appears to be a valuable solution to reach sustainable processes. Rapid and efficient synthesis of supported photocatalyst is still a remaining challenge and the choice of the support material is crucial. The present study aims at preparing a new generation of hybrid inorganic/organic photocatalysts based on silica mesoporous material and Eosin Y. These results highlight the influence of non-covalent interactions between the material support and the reagent impacting the selectivity of the reaction.
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3
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Assaf M, Martin-Gassin G, Prelot B, Gassin PM. Driving Forces of Cationic Dye Adsorption, Confinement, and Long-Range Correlation in Zeolitic Materials. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:1296-1303. [PMID: 35026117 DOI: 10.1021/acs.langmuir.1c03280] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Zeolitic materials are commonly used to capture emergent contaminants in water or complex aqueous effluents. The efficiency of this adsorption depends strongly on the guest-host interactions and on the surrounding environment with possible coadsorption of the solvent. Only a few experimental techniques are available to probe in situ the sequestration processes at the solid/liquid interface. We propose in the present work to combine the second harmonic scattering technique with isothermal titration calorimetry in order to investigate the adsorption and the confinement of a hemicyanine dye adsorbed inside faujasite materials. The methodology described here permits the quantification of the correlations between the confined dyes in the material and thus gives local information about the organization at the nanometer scale. Various impacts, such as the effect of the solvent type and the silicon to aluminum ratio of the zeolitic adsorbent, are quantitatively estimated and discussed. This work highlights that the most correlated system matches the higher adsorption capacity associated with the lower entropic contribution.
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Affiliation(s)
- Marwa Assaf
- ICGM, Université de Montpellier, ENSCM, CNRS, 34095 Montpellier, France
| | | | - Benedicte Prelot
- ICGM, Université de Montpellier, ENSCM, CNRS, 34095 Montpellier, France
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4
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Sanmartín RA, Salum ML, Protti S, Mella M, Bonesi SM. The Photoinduced Electrocyclization Reaction of Triphenylamine (TPA) in Sustainable and Confined Micellar Solutions: A Steady‐State and Laser Flash Photolysis Approach. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202100247] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rocío A. Sanmartín
- Universidad de Buenos Aires Facultad de Ciencias Exactas y Naturales Departamento de Química Orgánica Buenos Aires C1428EGA Argentina
- CONICET – Universidad de Buenos Aires Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR) Buenos Aires C1428EGA Argentina
| | - María L. Salum
- Universidad de Buenos Aires Facultad de Ciencias Exactas y Naturales Departamento de Química Orgánica Buenos Aires C1428EGA Argentina
- CONICET – Universidad de Buenos Aires Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR) Buenos Aires C1428EGA Argentina
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry University of Pavia V.le Taramelli 12 27100 Pavia Italy
| | - Mariella Mella
- Department of Chemistry University of Pavia V.le Taramelli 12 27100 Pavia Italy
| | - Sergio M. Bonesi
- Universidad de Buenos Aires Facultad de Ciencias Exactas y Naturales Departamento de Química Orgánica Buenos Aires C1428EGA Argentina
- CONICET – Universidad de Buenos Aires Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR) Buenos Aires C1428EGA Argentina
- PhotoGreen Lab, Department of Chemistry University of Pavia V.le Taramelli 12 27100 Pavia Italy
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5
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Quindt MI, Gola GF, Rodriguez CR, Ramirez JA, Bonesi SM. Product selectivity in the photoreaction of aryl sulfonates and mesylate of estrone derivatives in sustainable and micellar media: a steady-state investigation. NEW J CHEM 2022. [DOI: 10.1039/d2nj02989h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photochemical reaction of sulfonate steroids in a sustainable environment was carried out successfully under steady-state conditions. Significant selectivity in photoproduct formation was also observed.
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Affiliation(s)
- Matías I. Quindt
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina
- CONICET–Universidad de Buenos Aires, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), Buenos Aires, Argentina
| | - Gabriel F. Gola
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina
- CONICET–Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos Aplicados a Química Orgánica (UMYMFOR), Buenos Aires, Argentina
| | - Cristian R. Rodriguez
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina
- CONICET–Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos Aplicados a Química Orgánica (UMYMFOR), Buenos Aires, Argentina
| | - Javier A. Ramirez
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina
- CONICET–Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos Aplicados a Química Orgánica (UMYMFOR), Buenos Aires, Argentina
| | - Sergio M. Bonesi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina
- CONICET–Universidad de Buenos Aires, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), Buenos Aires, Argentina
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Candela RG, Lazzara G, Piacente S, Bruno M, Cavallaro G, Badalamenti N. Conversion of Organic Dyes into Pigments: Extraction of Flavonoids from Blackberries ( Rubus ulmifolius) and Stabilization. Molecules 2021; 26:molecules26206278. [PMID: 34684859 PMCID: PMC8538118 DOI: 10.3390/molecules26206278] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/08/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022] Open
Abstract
The blackberry’s color is composed mainly of natural dyes called anthocyanins. Their color is red–purple, and they can be used as a natural colorant. Anthocyanins are flavonoids, which are products of plants, and their colors range from orange and red to various shades of blue, purple and green, according to pH. In this study, the chemical composition of an extract obtained from blackberries was defined by LC-ESI/LTQOrbitrap/MS in positive and negative ionization mode. Furthermore, we investigated the adsorption process of blackberry extract using several inorganic fillers, such as metakaolin, silica, Lipari pumice, white pozzolan and alumina. The pigments exhibit different colors as a function of their interactions with the fillers. The analysis of the absorption data allowed the estimation of the maximum adsorbing capacity of each individual filler tested. Through thermogravimetric measurements (TGA), the thermal stability and the real adsorption of the organic extract were determined.
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Affiliation(s)
- Rossella G. Candela
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy; (R.G.C.); (M.B.)
| | - Giuseppe Lazzara
- Physics and Chemistry Department (DiFC), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy;
| | - Sonia Piacente
- Department of Pharmacy, University of Salerno, 84084 Fisciano (SA), Italy;
| | - Maurizio Bruno
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy; (R.G.C.); (M.B.)
| | - Giuseppe Cavallaro
- Physics and Chemistry Department (DiFC), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy;
- Correspondence: (G.C.); (N.B.)
| | - Natale Badalamenti
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy; (R.G.C.); (M.B.)
- Correspondence: (G.C.); (N.B.)
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7
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Induced selectivity in the photochemistry of estrone derivatives in sustainable and micellar environment: preparative and mechanistic studies. Photochem Photobiol Sci 2021; 21:625-644. [PMID: 34599462 DOI: 10.1007/s43630-021-00107-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/16/2021] [Indexed: 12/16/2022]
Abstract
In this study, we carried out preparative and mechanistic studies on the photochemical reaction of a series of 3-acylestrone derivatives in confined and sustainable micellar environment under steady-state conditions and the results were compared with those obtained in cyclohexane solution. The aim of this work is mainly focused to show whether the nature of the surfactant (cationic, neutral and anionic) leads to noticeable selectivity in the photoproduct formation. The 3-acylestrone derivatives underwent the photo-Fries rearrangement, with concomitant homolytic fragmentation of the ester group and [1;3]-acyl migration. This pathway afforded the ortho-acyl estrone derivatives, the main photoproducts together with estrone. However, epimerization of the ortho regioisomer 2-acetylestrone and estrone through Norrish Type I photoreaction occurred involving the fragmentation of the C-α at the carbonyl group (C-17) of the steroid. UV-visible and 2D-NMR (NOESY) spectroscopies have been employed to measure the binding constant Kb and the location of the steroids within the hydrophobic core of the micelle.
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8
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Siano G, Crespi S, Bonesi SM. Substituent and Surfactant Effects on the Photochemical Reaction of Some Aryl Benzoates in Micellar Green Environment †. Photochem Photobiol 2021; 97:1298-1309. [PMID: 33860538 DOI: 10.1111/php.13431] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 04/09/2021] [Indexed: 11/28/2022]
Abstract
In this study, we carried out preparative and mechanistic studies on the photochemical reaction of a series of p-substituted phenyl benzoates in confined and sustainable micellar environment. The aim of this work is mainly focused to show whether the nature of the surfactant (ionic or nonionic) leads to noticeable selectivity in the photoproduct formation and whether the electronic effects of the substituents affect the chemical yields and the rate of formation of the 5-substituted-2-hydroxybenzophenone derivatives. Application of the Hammett linear free energy relationship (LFER) on the rate of formation of benzophenone derivatives, on the lower energy band of the UV-visible absorption spectra of the aryl benzoates and 5-substituted-2-hydroxybenzophenone derivatives allows a satisfactory quantification of the substituent effects. Furthermore, UV-visible and 2D-NMR (NOESY) spectroscopies have been employed to measure the binding constant Kb and the location of the aryl benzoates within the hydrophobic core of the micelle. Finally, TD-DFT calculations have been carried out to estimate the energies of the absorption bands of p-substituted phenyl benzoates and 5-substituted-2-hydroxybenzophenone derivatives providing good linear correlation with those values measured experimentally.
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Affiliation(s)
- Gastón Siano
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Stefano Crespi
- Stratingh Institute for Chemistry, University of Groningen, Groningen, The Netherlands
| | - Sergio M Bonesi
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
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9
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Achiral Zeolites as Reaction Media for Chiral Photochemistry. Molecules 2019; 24:molecules24193570. [PMID: 31581744 PMCID: PMC6804131 DOI: 10.3390/molecules24193570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 11/17/2022] Open
Abstract
Obtaining enantiomerically-enriched photoproducts from achiral reactants has been a long-sought goal. The various methods developed to achieve chiral induction in photoproducts during the last fifty years still suffer from a lack of predictability, generality, and simplicity. With the current emphasis on green chemistry, obtaining enantiomerically enriched products via photochemistry is a likely viable alternative for the future. Of the various approaches developed during the last three decades, the one pioneered in the author's laboratory involved the use of commercially-available and inexpensive achiral zeolites as the media. This approach does not use any solvent for the reaction. Examples from these studies are highlighted in this article. Since no chiral zeolites were available, when the work was initiated in the author's laboratory, commercially-available zeolites X and Y were modified with chiral inductors so that the reaction space becomes chiral. The results obtained established the value of chirally-modified, commercial zeolites as media for achieving chiral induction in photochemical reactions. A recent report of the synthesis of a chiral zeolite is likely to stimulate zeolite-based chiral photochemistry in synthesizing enantiomerically-pure organic molecules. The availability of chiral zeolites in future is likely to energize research in this area. Our earlier observations on this topic, we believe, would be valuable for progress of the field. Keeping this in mind, I have summarized the work carried out in our laboratory on chiral photochemistry on chirally-modified zeolites. This review does not include examples where high chiral induction has been obtained via a strategy that examines molecules appended with chiral auxiliary within achiral and chirally-modified zeolites. The latter approach yields products with diastereomeric excess >80%.
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10
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Ioele G, De Luca M, Garofalo A, Ragno G. Photosensitive drugs: a review on their photoprotection by liposomes and cyclodextrins. Drug Deliv 2017; 24:33-44. [PMID: 29069944 PMCID: PMC8812581 DOI: 10.1080/10717544.2017.1386733] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Affiliation(s)
- Giuseppina Ioele
- Department of Pharmacy and Health and Nutrition Sciences, University of Calabria, Rende (CS), Italy
| | - Michele De Luca
- Department of Pharmacy and Health and Nutrition Sciences, University of Calabria, Rende (CS), Italy
| | - Antonio Garofalo
- Department of Pharmacy and Health and Nutrition Sciences, University of Calabria, Rende (CS), Italy
| | - Gaetano Ragno
- Department of Pharmacy and Health and Nutrition Sciences, University of Calabria, Rende (CS), Italy
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11
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Photoactive Nanomaterials Inspired by Nature: LTL Zeolite Doped with Laser Dyes as Artificial Light Harvesting Systems. MATERIALS 2017; 10:ma10050495. [PMID: 28772856 PMCID: PMC5459014 DOI: 10.3390/ma10050495] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 11/27/2022]
Abstract
The herein reported work describes the development of hierarchically-organized fluorescent nanomaterials inspired by plant antenna systems. These hybrid materials are based on nanostructured zeolitic materials (LTL zeolite) doped with laser dyes, which implies a synergism between organic and inorganic moieties. The non-interconnected channeled structure and pore dimensions (7.1 Å) of the inorganic host are ideal to order and align the allocated fluorophores inside, inferring also high thermal and chemical stability. These artificial antennae harvest a broad range of chromatic radiation and convert it into predominant red-edge or alternatively white-light emission, just choosing the right dye combination and concentration ratio to modulate the efficiency of the ongoing energy transfer hops. A further degree of organization can be achieved by functionalizing the channel entrances of LTL zeolite with specific tailor-made (stopcock) molecules via a covalent linkage. These molecules plug the channels to avoid the leakage of the guest molecules absorbed inside, as well as connect the inner space of the zeolite with the outside thanks to energy transfer processes, making the coupling of the material with external devices easier.
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12
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Morimoto D, Sato K, Saito K, Yagi M, Takagi S, Yui T. Color tuning of cationic pyrene derivatives on a clay nanosheet: Retardation of gradual redshift on clay. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.01.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Yu X, Wang L, Cohen SM. Photocatalytic metal–organic frameworks for organic transformations. CrystEngComm 2017. [DOI: 10.1039/c7ce00398f] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal–organic frameworks (MOFs) have attracted increasing attention for applications in heterogeneous photocatalysis.
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Affiliation(s)
- Xiao Yu
- Department of Nanoengineering
- University of California
- San Diego
- USA
- Department of Chemistry and Biochemistry
| | - Le Wang
- Department of Chemistry and Biochemistry
- University of California
- San Diego
- USA
| | - Seth M. Cohen
- Department of Chemistry and Biochemistry
- University of California
- San Diego
- USA
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14
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Iguchi D, Erra-Balsells R, Bonesi SM. Photo-Fries rearrangement of aryl acetamides: regioselectivity induced by the aqueous micellar green environment. Photochem Photobiol Sci 2016; 15:105-16. [DOI: 10.1039/c5pp00349k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NMR spectroscopy shows the location of acetanilides within the shells and hydrophobic cores in micellar solutions. Irradiation of acetanilides in aqueous micellar solutions involves C–N homolytic cleavage to yield singlet radical pairs that selectively provide 2-aminoacetophenone derivatives.
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Affiliation(s)
- Daniela Iguchi
- CIHIDECAR – CONICET
- Departamento de Química Orgánica
- FCEyN
- University of Buenos Aires
- Pabellón 2
| | - Rosa Erra-Balsells
- CIHIDECAR – CONICET
- Departamento de Química Orgánica
- FCEyN
- University of Buenos Aires
- Pabellón 2
| | - Sergio M. Bonesi
- CIHIDECAR – CONICET
- Departamento de Química Orgánica
- FCEyN
- University of Buenos Aires
- Pabellón 2
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15
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Ramamurthy V, Mondal B. Supramolecular photochemistry concepts highlighted with select examples. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2015. [DOI: 10.1016/j.jphotochemrev.2015.04.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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16
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Sato K, Matsubara K, Hagiwara S, Saito K, Yagi M, Takagi S, Yui T. Remarkable stimulation of emission quenching on a clay surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:27-31. [PMID: 25540843 DOI: 10.1021/la504597t] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Tetra-cationic pyrene derivative (Py(4+)) and tris(bipyridine)ruthenium(II) (Ru(2+)) were hybridized onto the surface of a synthesized clay. We observed the remarkable stimulation of excited Py(4+) emission quenching on the clay surface, with a very large apparent quenching rate constant (kq = 7.4 ± 0.7 × 10(15) L mol(-1) s(-1)).
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Affiliation(s)
- Keita Sato
- Department of Material Science and Technology, Faculty of Engineering, and Center for Transdisciplinary Research, Niigata University , 8050 Ikarashi-2, Niigata 950-2181, Japan
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17
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Douhal A, Alarcos N, Cohen B. Photodynamics of a Proton-Transfer Dye in Solutions and Confined Within NaX and NaY Zeolites. J Phys Chem B 2014; 118:19431-19443. [PMID: 25060093 DOI: 10.1021/jp505591k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on steady-state, picosecond and femtosecond time-resolved emission studies of 2-(2'-hydroxyphenyl)benzoxazole (HBO) in solutions and interacting with NaX and NaY zeolites. In solutions, an ultrafast (less than 150 fs) excited-state intramolecular proton-transfer (ESIPT) reaction takes place in syn-enol form, and leads to keto-type tautomer. We also observed a torsional motion in the keto form (~20 ps in dichloromethane, DCM). For NaX and NaY DCM suspensions, anionic forms interacting with the zeolites at S0 and S1 states are generated. They show two fluorescence lifetimes in both zeolites (720 ps and 2.4 ns for NaY and 960 ps and 2.7 ns for NaX), while those of the enol bonded to the zeolite framework and of the free keto forms are ~100 and 250 ps, respectively. The ultrafast dynamics of the anion in alkaline solutions reveals two deactivation pathways: an intramolecular charge transfer (ICT, 1.2 ps) and a twisting motion, affected by the viscosity of the solvent (12 and 20 ps for MeOH and ethylene glycol). When HBO is interacting with NaX and NaY the twisting motion is cancelled, while the ICT becomes slower as a result of a combination of several environment effects. HBO anions within the faujasite framework show also a ~ 30 ps decay associated to a non-fluorescent (n, π*) state. Our results demonstrate how intermolecular H-bonds, the confinement and the electrostatic interactions of HBO with the used materials, affect its ground as well as its excited state properties. Our findings add new knowledge on the interactions of silica-based nanomaterials containing the H-bonding guests.
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18
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Nguyen TT, Ersen O, Serp P. Selective Confinement of Ruthenium Nanoparticles in Silica Nanotubes. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T. Trang Nguyen
- Laboratoire de Chimie de Coordination UPR CNRS 8241, composante ENSIACET, Université de Toulouse UPS‐INP‐LCC 4 allée Emile Monso, BP 44362, 31030 Toulouse Cedex 4, France, http://www.lcc‐toulouse.fr/lcc/spip.php?article265
| | - Ovidiu Ersen
- IPCMS – Groupe Surfaces et Interfaces, CNRS – ULP UMR 7504, 23 Rue du Loess, BP 43, 67034 Strasbourg, France
| | - Philippe Serp
- Laboratoire de Chimie de Coordination UPR CNRS 8241, composante ENSIACET, Université de Toulouse UPS‐INP‐LCC 4 allée Emile Monso, BP 44362, 31030 Toulouse Cedex 4, France, http://www.lcc‐toulouse.fr/lcc/spip.php?article265
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19
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Hallett-Tapley GL, Schepp NP, Cozens FL. The reactivity of diarylmethyl carbocations within non-protic zeolites. CAN J CHEM 2011. [DOI: 10.1139/v10-150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The generation of diarylmethyl carbocations within non-protic zeolites (LiY, NaY, KY, RbY, CsY, and NaX) was carried out via laser excitation (266 nm or 266 nm / 308 nm) of diarylacetic acids. Rapid loss of CO2, followed by photochemical oxidation of the diarylmethyl radicals resulted in the formation of the diarylmethyl carbocations. The reactivity of the diarylmethyl carbocations was found to be highly dependent on the alkali metal counterion and the Si/Al ratio of the zeolite framework. Furthermore, the effect of various para-electron donating substituents (4-H, 3-CH3, 4-CH3, 4,4′-CH3, and 4-OCH3) on the diarylmethyl carbocation reactivity was investigated. Comparison of the Hammett plots constructed for the reactivity of the diarylmethyl carbocations in zeolites with those in solution (CH3CN–H2O (1:2) and TFE) showed decreased sensitivity of the electrophilic species towards para-electron donating substituents in the heterogeneous media. The leveling effect observed in the zeolite Hammett plots has been attributed to the presence of an isokinetic relationship, specifically, a low isokinetic temperature for the reaction of diarylmethyl carbocations with the aluminosilicate zeolite framework.
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Affiliation(s)
| | - Norman P. Schepp
- Department of Chemistry, Dalhousie University, Halifax, NS B3H 4J3, Canada
| | - Frances L. Cozens
- Department of Chemistry, Dalhousie University, Halifax, NS B3H 4J3, Canada
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Park SY, Yu H, Park J, Jang DJ. Excited-state prototropic equilibrium dynamics of 6-hydroxyquinoline encapsulated in microporous catalytic faujasite zeolites. Chemistry 2011; 16:12609-15. [PMID: 20853278 DOI: 10.1002/chem.201000734] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The excited-state proton transfer and geminate recombination of 6-hydroxyquinoline (6HQ) encaged in catalytic Na(+)-exchanged faujasite zeolites X (NaX) and Y (NaY) have been explored by measuring steady-state and picosecond time-resolved spectra. The pathways and rate constants of proton transfer of excited 6HQ are determined by the microscopic environment of zeolitic hosts surrounding the guest molecules. The excited-state proton transfer of a 6HQ molecule encapsulated in a zeolitic nanocavity is initiated by deprotonation of the enolic group to form an anionic intermediate and completed by subsequent protonation of the imino group to form a zwitterionic tautomer. Geminate recombination occurs to compete with proton transfer at each tautomerization step of excited-state 6HQ because of the confined environment of dehydrated zeolitic supercages. Consequently, excited-state equilibria among three prototropic species of 6HQ are established in microporous catalytic faujasite zeolites. Kinetic differences in NaX and NaY are attributed to dissimilarities in acidity/basicity.
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Affiliation(s)
- Sun-Young Park
- School of Chemistry, Seoul National University, NS60, Seoul 151-742, Korea
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21
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Development of molecularly imprinted polymers as tailored templates for the solid-state [2+2] photodimerization. Biosens Bioelectron 2009; 25:640-6. [DOI: 10.1016/j.bios.2009.01.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 01/08/2009] [Accepted: 01/13/2009] [Indexed: 11/17/2022]
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22
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Yui T, Hirano T, Okazaki KI, Inoue H, Torimoto T, Takagi K. Photocatalytic electron flow through the interface of titania nanosheets and mesoporous silica hybrid films. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2008.12.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Asymmetric induction in an intramolecular [2+2] photocycloaddition within chirally modified zeolite supercages. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.02.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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25
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Exchanged zeolites with transition metals of the first period as photocatalyts for n-hexadecane degradation. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.molcata.2008.03.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Batonneau-Gener I, Moissette A, Brémard C, Buntinx G. Time resolved resonance Raman, transient diffuse reflectance and kinetic studies of species generated by UV laser photolysis of biphenyl occluded within dehydrated Y-faujasite zeolites. J Photochem Photobiol A Chem 2008. [DOI: 10.1016/j.jphotochem.2007.09.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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27
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Ricci A, Chrétien MN, Sayari A, Scaiano JC. Photophysical Properties of Methyl Triazone Included in MCM-41¶. Photochem Photobiol 2007. [DOI: 10.1111/j.1751-1097.2005.tb01468.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Moorthy JN, Koner AL, Samanta S, Singhal N, Nau WM, Weiss RG. Diastereomeric Discrimination in the Lifetimes of Norrish Type II Triplet 1,4-Biradicals and Stereocontrolled Partitioning of Their Reactivity (Yang Cyclization versus Type II Fragmentation). Chemistry 2006; 12:8744-9. [PMID: 16933349 DOI: 10.1002/chem.200600880] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The stereochemistry at C2 and C3 carbons controls the partitioning of triplet 1,4-biradicals of ketones 2 among various pathways. Differences in the major reaction pathways, for example, cyclization (syn) and fragmentation (anti), adopted by the diastereomeric 1,4-radicals of ketones 2 have permitted unprecedented diastereomeric discrimination in their lifetimes to be observed by nanosecond laser flash photolysis. From quantum yield measurements and transient lifetime data, the absolute rate constants for cyclization and fragmentation of a pair of diastereomeric triplet 1,4-biradicals have been determined for the first time.
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TAKAGI S, EGUCHI M, TRYK D, INOUE H. Porphyrin photochemistry in inorganic/organic hybrid materials: Clays, layered semiconductors, nanotubes, and mesoporous materials. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2006. [DOI: 10.1016/j.jphotochemrev.2006.04.002] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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30
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Matsuo Y, Fukutsuka T, Sugie Y. Monomeric Dispersion of Covalently Attached Pyrene Chromophores in Silylated Graphite Oxide. CHEM LETT 2006. [DOI: 10.1246/cl.2006.530] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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31
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Yui T, Tsuchino T, Akatsuka K, Yamauchi A, Kobayashi Y, Hattori T, Haga MA, Takagi K. Visible Light-Induced Electron Transfers in Titania Nanosheet and Mesoporous Silica Integrated Films. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.386] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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32
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Yui T, Kobayashi Y, Yamada Y, Tsuchino T, Yano K, Kajino T, Fukushima Y, Torimoto T, Inoue H, Takagi K. Photochemical electron transfer though the interface of hybrid films of titania nano-sheets and mono-dispersed spherical mesoporous silica particles. Phys Chem Chem Phys 2006; 8:4585-90. [PMID: 17047756 DOI: 10.1039/b609779k] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Photochemical Electron Transfer (ET) between an organic dye, the porphyrin derivative TMPyP, and an electron acceptor, methyl viologen MV2+, have been investigated at the interface of two different inorganic films, i.e., layered titania nano-sheets (TNS) and a monolayer film of spherical and mono-dispersed mesoporous silica (sMPS) particles (ca. 0.5 microm). TMPyP ions were intercalated within the sMPS nano-cavities to form (TMPyP-sMPS) while MV2+ ions were intercalated into the TNS interlayers to form (MV2+-TNS). The (TMPyP-sMPS) and (MV2+-TNS) films were then stacked on a silica substrate in this order to form a (MV2+-TNS)/(TMPyP-sMPS) film and, upon UV light irradiation, ET could be induced. However, when this film was stacked inversely, i.e., for the (TMPyP-sMPS)/(MV2+-TNS) films on a silica substrate, no photoinduced ET were observed. Interestingly, however, even for this photo-inactive inversely stacked film, ET could be generated by inserting a gold vapor-deposited layer between the (MV2+-TNS) and (TMPyP-sMPS) films. The conjugation conditions at the interface of the inversely stacked (TMPyP-sMPS)/(MV2+-TNS) hybrid film were, thus, confirmed to strongly affect the photoinduced electron transfers and their efficiencies.
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Affiliation(s)
- Tatsuto Yui
- Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya, 464-8603, Japan.
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Chen YZ, Wu LZ, Zhang LP, Tung CH. Confined Space-Controlled Hydroperoxidation of Trisubstituted Alkenes Adsorbed on Pentasil Zeolites. J Org Chem 2005; 70:4676-81. [PMID: 15932304 DOI: 10.1021/jo050081n] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photosensitized oxidation of trialkylalkenes 2-methyl-2-pentene (1), 1-methylcyclohexene (2), trans-3-methyl-2-pentene (3), cis-3-methyl-2-pentene (4), and 2-methyl-2-butene (5) included in the internal framework of Na-ZSM-5 zeolites was investigated. The zeolite samples having adsorbed the alkenes were suspended in isooctane, and the sensitizer, tetraphenylporphyrin (TPP), was dissolved in the solution. Singlet oxygen produced in the solution diffused into the internal framework of the zeolites and reacted with alkenes. For all the substrates studied, the ene-type allylic hydroperoxides were obtained in a highly regioselective manner. The regiochemistry for 1-4 in favor of the allylic hydrogen abstraction from the largest substituents is in contrast to their photooxidation within the dye-supported zeolite Na-Y, where the secondary hydroperoxides are preferentially produced. The tight confinement of the alkenes within the narrow channels of the ZSM-5 zeolites is likely to be responsible for this selectivity.
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Affiliation(s)
- Yu-Zhe Chen
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100101, China
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Aspée A, Maretti L, Scaiano JC. Monitoring photodecomposition of dibenzyl ketone within NaY zeolite with a pre-fluorescent nitroxide compound. Photochem Photobiol Sci 2005; 2:1125-9. [PMID: 14690224 DOI: 10.1039/b308638k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Benzyl radicals derived from photodecomposition of dibenzyl ketone have been monitored in NaY zeolite using the pre-fluorescent probe 4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidine-1-oxyl free radical (QT). The steady-state and time-resolved fluorescence show a strong interaction of QT within the zeolite cavities. Furthermore, the increase in the fluorescence with the irradiation time reveals the efficient trapping of benzyl radicals by QT under vacuum. Dispersion of the zeolite composites in liquid polymers results in an improvement in the fluorescence measurement and faster kinetics in comparison with the solid samples. These results are interpreted in terms of partial refractive index matching as a consequence of polymer reptation into the zeolite cavities. Analysis of the fluorescence lifetime distribution shows the presence of different fluorescence ensembles with different fluorescence quantum yields, depending on the microenvironment within the zeolite particle. Pre-fluorescent probes offer a novel and useful methodology for studying radical processes in zeolites.
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Affiliation(s)
- Alexis Aspée
- Department of Chemistry, University of Ottawa, 10 Mari-Curie, Ottawa, Ontario, Canada K1N 6N5
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35
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Pace A, Buscemi S, Vivona N. Heterocyclic Rearrangements in Constrained Media. A Zeolite-Directed Photorearrangement of 1,2,4-Oxadiazoles. J Org Chem 2005; 70:2322-4. [PMID: 15760221 DOI: 10.1021/jo047910+] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] The first intrazeolite-photoinduced rearrangement of a five-membered heterocycle is reported. A completely different behavior compared to solution irradiations has been observed. The zeolite's role in directing the photoreaction of 3-phenyl-1,2,4-oxadiazoles toward the formation of the corresponding 1,3,4-oxadiazoles in a ring contraction-ringexpansion route is discussed.
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Affiliation(s)
- Andrea Pace
- Dipartimento di Chimica Organica "E. Paterno", Università degli Studi di Palermo, Viale delle Scienze-Parco d'Orleans II, I-90128 Palermo, Italy.
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36
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Ricci A, Chrétien MN, Sayari A, Scaiano JC. Photophysical Properties of Methyl Triazone Included in MCM-41¶. Photochem Photobiol 2005. [DOI: 10.1562/2005-03-19-rn-466r.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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37
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Mori T, Izumi H, Inoue Y. Chiroptical Properties of Organic Radical Cations. The Electronic and Vibrational Circular Dichroism Spectra of α-Tocopherol Derivatives and Sterically Hindered Chiral Hydroquinone Ethers. J Phys Chem A 2004. [DOI: 10.1021/jp0463520] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tadashi Mori
- Department of Molecular Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba West, 16-1, Onogawa, Tsukuba, Ibaraki 305-8569, Japan, and Entropy Control Project, ICORP, JST, 4-6-3 Kamishinden, Toyonaka 560-0085, Japan
| | - Hiroshi Izumi
- Department of Molecular Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba West, 16-1, Onogawa, Tsukuba, Ibaraki 305-8569, Japan, and Entropy Control Project, ICORP, JST, 4-6-3 Kamishinden, Toyonaka 560-0085, Japan
| | - Yoshihisa Inoue
- Department of Molecular Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba West, 16-1, Onogawa, Tsukuba, Ibaraki 305-8569, Japan, and Entropy Control Project, ICORP, JST, 4-6-3 Kamishinden, Toyonaka 560-0085, Japan
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Maldotti A, Molinari A, Amadelli R. Photocatalysis with organized systems for the oxofunctionalization of hydrocarbons by O2. Chem Rev 2002; 102:3811-36. [PMID: 12371903 DOI: 10.1021/cr010364p] [Citation(s) in RCA: 398] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrea Maldotti
- Dipartimento di Chimica, Università degli Studi di Ferrara e ISOF CNR Sezione di Ferrara, Via Luigi Borsari 46, 44100 Ferrara, Italy.
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Ozer RR, Ferry JL. Photocatalytic Oxidation of Aqueous 1,2-Dichlorobenzene by Polyoxometalates Supported on the NaY Zeolite. J Phys Chem B 2002. [DOI: 10.1021/jp0138126] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ruya R. Ozer
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - John L. Ferry
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
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Chong KCW, Sivaguru J, Shichi T, Yoshimi Y, Ramamurthy V, Scheffer JR. Use of chirally modified zeolites and crystals in photochemical asymmetric synthesis. J Am Chem Soc 2002; 124:2858-9. [PMID: 11902861 DOI: 10.1021/ja016989m] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three different approaches to asymmetric induction in the cis-to-trans photoisomerization of a number of 1-benzoyl-2,3-diphenylcyclopropane derivatives are reported: the use of chiral inductors and covalent chiral auxiliaries in MY zeolites and the use of ionic chiral auxiliaries in crystals. High levels of asymmetric induction were achieved using the latter two methods-up to 71% through the use of covalent chiral auxiliaries in zeolites and a remarkable 99% via the solid state ionic chiral auxiliary approach. In the zeolite method, the diastereomeric excess was found to depend strongly on the nature of the zeolite cation, M(+), and in the ionic chiral auxiliary approach, evidence is presented that it is the fixed orientation of the benzoyl group with respect to the cyclopropane ring that controls enantioselectivity in the crystalline state-a finding that is directly relevant to theoretical work on this topic.
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Affiliation(s)
- Kenneth C W Chong
- Department of Chemistry, University of British Columbia, Vancouver, Canada V6T 1Z1
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