References of "Mendoza Gallego, Carlos"
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See detailHeterogeneous singlet oxygen generation: in-operando visible light EPR spectroscopy
Mendoza Gallego, Carlos ULiege; Désert, Anthony; Khrouz, Lhoussain et al

in Environmental Science and Pollution Research (2019)

The use of photosensitizers immobilized on mesoporous materials to produce singlet oxygen (1O2) has opened a new way to synthetic and environmental applications due to the fast development of flow ... [more ▼]

The use of photosensitizers immobilized on mesoporous materials to produce singlet oxygen (1O2) has opened a new way to synthetic and environmental applications due to the fast development of flow photochemistry and continuous-flow microreactors. 1O2-based photosensitized processes can be employed for the degradation of organic pollutants in aqueous medium and the photosensitizer can be covalently attached to the support and separated from the effluent reducing the environmental impact. The aim of the present paper is to evaluate the 1O2 generation of Rose Bengal (RB) in homogeneous and heterogeneous systems using in-operando evaluation. Mesoporous SiO2 nanoparticles (MSNs) were successfully conjugated with RB (MSN-RB) and Electron Paramagnetic Resonance (EPR) spectroscopy in combination with the spin trap TEMP was employed to obtain paramagnetic TEMPO via generated 1O2 when RB or MSN-RB are exposed to visible light. Additionally, EPR/DMPO was used to exclude the possible generation of other reactive oxygen species (ROS) by the functionalized nanoparticles. We found that in situ 1O2 generation was enhanced when the same amount of RB is immobilized inside of mesoporous SiO2. [less ▲]

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See detailImproving Continuous Flow Singlet Oxygen Photooxygenations with Functionalized Mesoporous Silica Nanoparticles
Mendoza Gallego, Carlos ULiege; Emmanuel, Noémie ULiege; Pàez Martinez, Carlos ULiege et al

in ChemPhotoChem (2018)

Continuous flow photochemistry relying on photosensitizers faces two main challenges: the photodegradation (bleaching) and the downstream removal of the photosensitizer. Rose Bengal (RB) is a common ... [more ▼]

Continuous flow photochemistry relying on photosensitizers faces two main challenges: the photodegradation (bleaching) and the downstream removal of the photosensitizer. Rose Bengal (RB) is a common photosensitizer utilized for photooxygenations with singlet oxygen (1O2), but is notoriously sensitive to photobleaching and difficult to remove from reactor effluents. The heterogenization of photosensitizers on mesoporous silica nanoparticles (MSNs) is arguably a viable option for such applications. Herein, we report on the use of RB covalently incorporated into MSNs (RB@MSNs) for photooxygenations under continuous flow conditions. RB@MSNs enable the 1O2 photooxygenation of various organic substrates upon irradiation with 540 nm LEDs. A series of organic substrates were evaluated including methionine, α‐terpinene, 2‐furoic acid, triphenylphosphine, citronellol and cyclopentadiene. These results emphasize an improved resistance to photobleaching, and the possibility to use RB@MSNs as easily recoverable catalyst, which could be removed from the reactor effluent either (a) by centrifugation or (b) in‐line membrane filtration. [less ▲]

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See detailAu bipyramids/mSiO2 core-shell nanoparticles and their metal-enhanced generation of singlet oxygen – Application in photooxygenations
Mendoza Gallego, Carlos ULiege; Château, Denis; Désert, Anthony et al

Conference (2018, July 24)

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit ... [more ▼]

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit intense and well-defined plasmon resonance, easily tunable with the aspect ratio and synergy between Au NPs and chromophores can enhance the photophysical properties of nearby molecules. In Rose Bengal-NPs systems for the production of singlet oxygen (1O2), it is now well established that the control of the dye-to-NP distance ranging from 10 to 20 nm is crucial to achieve the proper coupling between plasmon resonance and the dye1. We have developed AuBPs@mesoporous SiO2 core-shell nanostructures to control the distance between metallic surface and photosensitizers in order to increase the production of 1O2 through metal-enhanced fluorescence (MEF). An enhancement of 1O2 generation has been shown with the obtained anisotropic AuBPs and AuBPs@mSiO2 in presence of RB using different methods of 1O2 quantification. They are of interest to the application in photooxygenation reactions e.g. α –terpinene to ascaridole. [less ▲]

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See detailFrom well-defined plasmonic nanoparticles to hybrid materials for photonic and catalytic applications
Mendoza Gallego, Carlos ULiege; Heinrichs, Benoît ULiege; Désert, Anthony et al

Conference (2018, July 19)

Our team develops research on hybrid materials devoted to optical applications, especially in the fields of optical protection, bioimaging, photocatalysis. In particular the expertise lies in the design ... [more ▼]

Our team develops research on hybrid materials devoted to optical applications, especially in the fields of optical protection, bioimaging, photocatalysis. In particular the expertise lies in the design of original molecular systems, coupled with inorganic materials like plasmonic nanostructures and the characterization of optical interactions and responses (absorption, emission, nonlinear responses…). In this context and through various studies, we will see the benefits and the way to use gold nanoparticles, from their well-controlled synthesis, and also their functionalization and incorporation in hybrid materials, to their impact on the optical and catalytic properties. Among numerous classes of nanoparticles like spheres, hollow spheres or nanorods, we have particularly investigated gold nano-bipyramids (AuBPs) for several years. Indeed, these AuBPs exhibit intense and well-defined plasmon resonance, easily tunable with the aspect ratio, and also strong localized electromagnetic field in the vicinity of the tips. Currently, our optimized synthesis method leads to well-designed AuBPs in high yield and in high concentration, with a sharp plasmon band tunable from 650 nm up to 2000 nm. We have recently developed an easy and general gold surface modification by a functional thiolated silicon polymer. In addition to be an alternative to the use of surfactants or long-chain polymers in order to provide efficient colloidal stabilization in a wide range of solvent, this surface modification allows us to prepare homogeneous hybrid materials like gold-doped sol-gel silica presenting clear plasmon band. Association with various photoactive compounds have been explored and positive impact such as enhancement have been shown for photocatalytic properties of SiO2/TiO2 films, or for non-linear optical absorption of dye-doped glasses. Finally, we will present in particular our current efforts to synthetize core-shell AuBP@SiO2 NPs combining with rose Bengal for catalysis based on singlet oxygen generation. [less ▲]

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See detailRB@Au/mSiO2 core-shell nanobipyramids for the enhanced-production of singlet oxygen
Mendoza Gallego, Carlos ULiege; Désert, Anthony; Château, Denis et al

Conference (2018, July 16)

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle. The size and geometry of Au NPs can be ... [more ▼]

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle. The size and geometry of Au NPs can be tuned by simply changing the experimental parameters in order to obtain different shapes tuning the wavelength where the maximum plasmon is located. Au bipyramids exhibit intense and well-defined plasmon resonance, easily tunable with the aspect ratio, and also strong localized electromagnetic field in the vicinity of the tips. Currently, our synthesis method leads to well-designed AuBPs in high yield and in high concentration, with a plasmon band located at 650 nm. Combining the ability to modulate the optical response of these NPs and to functionalize their surface with photosensitizers opens the way to new families of luminescent organic-inorganic materials. Synergy between Au NPs and chromophores has become a feasible way to control and modify optical effects. This control and understanding of PS-NP interactions have attracted many scientists and a wide range of publications report the fluorescence quenching or enhancement of the photophysical properties of nearby molecules. The presence of a dye in the vicinity of a metallic surface can lead to the limitation in the dye photobleaching. Rose Bengal (RB) is a metal-free, non-toxic, and popular PS that shows intense absorption bands in the green region of the visible spectrum (480-550 nm), and is renowned for its high quantum yield (ϕΔ = 0.76) for the generation of 1O2. In RB-NPs systems, it is now well established that the control of the dye-to-nanoparticle distance at the surface of the NPs is crucial to achieve the proper coupling between the plasmon resonance and the dye. RB needs to be located in a suitable distance ranging from 10 to 20 nm to achieve optimum emission enhancement according to literature. We have developed an easy method to control the distance between metallic surface and the photosensitizer with the SiO2 thickness in order to increase the production of singlet oxygen. An enhancement has been shown for the obtained anisotropic RB@Au/mSiO2 during photooxygenation model reactions in comparison with previous works. [less ▲]

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See detailFunctionalization of mesoporous silica nanoparticles with Rose Bengal for heterogeneous photooxygenation reactions in microfluidic systems
Mendoza Gallego, Carlos ULiege; Emmanuel, Noémie ULiege; Pàez Martinez, Carlos ULiege et al

Poster (2018, July 09)

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules[1]. There are various methodologies for the production of ... [more ▼]

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules[1]. There are various methodologies for the production of singlet oxygen, among which the most popular involves a photoinduced electronic energy transfer from an excited state of a catalytic photosensitizer (PS) to triplet oxygen (3O2)[2]. The amino acids tyrosine, tryptophan, methionine, histidine and cysteine constitute one of the most relevant families among the photooxidizable biological substrates due to their areas of high electron density because of double bonds or sulfur moieties. Of particular interest is the photooxidation of methionine (Met) to methionine sulfoxide (MetO). In general, sulfoxides are frequently used in organic synthesis, pharmaceutical science, biochemistry and material science. However, the classical methods to oxidize sulfides to sulfoxides present a high risk of overoxidation to sulfones. In particular, MetO is a particularly valuable synthetic intermediate with applications ranging from peptide sciences, material sciences, to organic synthesis. PSs are commonly organic dyes bearing a (hetero)aromatic core such as Rose Bengal, Methylene Blue, Erythrosin B, porphyrins, phtalocyanines, and related tetrapyrroles. Rose Bengal (RB) is a popular photosensitizer that has been widely utilized for the production of 1O2 upon visible light aerobic irradiation[3]. The functionalization of mesoporous silica nanoparticles (MSNs) with PSs has attracted great research attention during last years to design efficient nanoplatforms to be used in nanomedicine as drug delivery systems or in targeted photodynamic cancer therapy (PDT) owing to their biocompatibility, high RB loading capacity and ease of surface functionalization, but its use as catalyst support in photooxygenation reactions is still a challenge. Regarding the use of RB under continuous-flow photocatalytic conditions and the configuration of the flow setup, three main strategies emerge from the literature based on the use of (a) homogeneous PSs, (b) packed-bed photoreactors with heterogeneous PSs embedded on the packing material and (c) heterogeneous PSs concomitantly fed with the substrate. Although each strategy comes with assets and drawbacks, the use of free flowing heterogeneous PSs is supposedly the most interesting option, as far as, besides their efficiency, (a) they (a) are readily prepared, (b) do not accumulate within the micro/mesoreactor channels or cause clogging and (c) are easily removed downstream. RB can be protected from photobleaching during important light exposures by a mesoporous SiO2 structure[4]. Synthesis of MSNs was made following well-known methods and the immobilization of RB at the surface of SiO2 by a covalent bond was carried out by two coupling agents: 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and (1-[Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate) (HATU). A complete characterization of RB@MSNs was made by BET, Tg-MS, UV-Vis and TEM. Finally, the influence of key parameters like RB concentration and the liquid flow were studied as a function of the coupling agent used in a microfluidic system. The efficiency of methionine photooxygenation as well as the photobleaching of the dye was followed by Proton Nuclear Magnetic Resonance (1H NMR). This work converts MSNs in interesting support for new and clean heterogeneous continuous-flow photooxygenations. Taken together, our results show that heterogenization of PS for 1O2 production in microreactors is possible by grafting RB into MSNs by a covalent bond. This attachment is able to avoid the photobleaching of the dye and allows separating the solid support with the PS from the reactor effluent and reutilizing the PS. The potential of these NPs to be used as heterogeneous catalyst for photooxygenation of methionine has been demonstrated. [less ▲]

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See detailRose Bengal@MSNs as heterogeneous photocatalysts in photooxygenation reactions
Mendoza Gallego, Carlos ULiege; Emmanuel, Noémie ULiege; Pàez Martinez, Carlos ULiege et al

Conference (2018, June 19)

The functionalization of mesoporous silica nanoparticles (MSNs) with photosensitizers e.g. Rose Bengal (RB) has attracted great research attention during last years to design efficient nanoplatforms to be ... [more ▼]

The functionalization of mesoporous silica nanoparticles (MSNs) with photosensitizers e.g. Rose Bengal (RB) has attracted great research attention during last years to design efficient nanoplatforms to be used in nanomedicine as drug delivery systems or in targeted photodynamic cancer therapy (PDT) owing to their biocompatibility, high loading capacity and ease of surface functionalization. Additionally, its use as catalyst support in photooxygenation reactions via singlet oxygen (1O2) can produce high-value added organic molecules in continuous-flow microreactors decreasing the environmental impact due to the possibility to recover the solid catalyst from the reactor effluent and reutilize the photosensitizer. Various model organic substrates were tested as previously reported for homogeneous photooxygenation reactions including bio-sourced methionine [1] and α-terpinene as well as 2-furoic acid, triphenylphosphine, citronellol and cyclopentadiene. The immobilization of the dye inside mesoporous silica nanoparticles plays a strategic role in preserving the chemical integrity of the photosensitizer as demonstrated by UV-Vis spectroscopy. The mechanism of photooxygenation by 1O2 could be influenced by the state of the dye, avoiding the ground state complexation between the amino acid and the photosensitizer as occurs in homogeneous systems. Moreover, heterogeneous photooxygenation of several substrates in order to obtain high-value added organic molecules. High conversions were achieved with methionine, α-terpinene in 72 s and triphenylphosphine in 300 s. However, the heterogeneous 1O2 photooxygenation of cyclopentadiene into cis-2-cyclopentadiene-1,4-diol provided a complete conversion in 51 s of residence time. Our results show that heterogenization of PS for 1O2 production in microreactors is possible by grafting RB into MSNs by a covalent bond. This attachment is able to avoid the photobleaching of the dye and allows separating the solid support with the PS from the reactor effluent and reutilizing the PS in different cycles. The potential of these NPs to be used as heterogeneous catalyst for photooxygenation of several organic substrates has been demonstrated. [less ▲]

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See detailTransitioning from conventional batch to microfluidic processes for the efficient singlet oxygen photooxygenation of methionine
Mendoza Gallego, Carlos ULiege; Emmanuel, Noémie ULiege; Pàez Martinez, Carlos ULiege et al

in Journal of Photochemistry and Photobiology A: Chemistry (2018), 356

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules. Among organic substrates, bio-sourced molecules such as ... [more ▼]

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules. Among organic substrates, bio-sourced molecules such as aminoacids or terpenes have a promising forecast as synthetic building blocks. A pseudo first-order kinetic study for the photocatalytic oxygenation of natural amino acid (L)-methionine was carried out in a macroscopic batch reactor. Various parameters were studied, including the effect of the photosensitizer (Rose Bengal, RB) concentration, the intensity of the light and the O2 flow in terms of apparent kinetic constants and space-time yields. The identification of important limiting parameters as pressure, gas flow or light efficiency during the photocatalytic oxygenation of methionine allowed its transition from macroscopic batch reactor to continuous-flow microreactor. [less ▲]

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See detailProtective nature of nano-TiN coatings shaped by EPD on Ti substrates
Mendoza Gallego, Carlos ULiege; Gonzalez, Zoilo; Gordo, Elena et al

in Journal of the European Ceramic Society (2018), 38(2), 495-500

The hardness and corrosion resistance of TiN coatings, processed by Electrophoretic Deposition (EPD) to cover polished and unpolished Ti substrates, have been evaluated. A deposition time of 5 min has ... [more ▼]

The hardness and corrosion resistance of TiN coatings, processed by Electrophoretic Deposition (EPD) to cover polished and unpolished Ti substrates, have been evaluated. A deposition time of 5 min has been enough to obtain a cohesive layer of 7–8 μm in thickness. The coatings were thermally treated in vacuum atmosphere at 1200 °C for 1 h with heating and cooling rates of 5 °C min−1. The surfaces have been covered homogeneously optimizing the properties of the Ti substrates. Uniform and dense TiN coatings have been obtained onto polished substrates, while on unpolished Ti the nitrogen diffuses toward the substrate, moderately dissolving TiN coating. The nanohardness values of the polished samples have been increased from 2.8–4.8 GPa up to 6.5–8.5 GPa. Besides, the corrosion current density has been reduced more than one order of magnitude obtaining a protective efficiency of 82%. These values have been compared with other works in literature where authors used complex and costly processing techniques, demonstrating the strong impact of the colloidal processing over the specific properties of the material. [less ▲]

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See detailIntegrated continuous flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Winter, Marc et al

Poster (2018, February 06)

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See detailGold bipyramids/SiO2 core-shell nanoparticles for an enhanced generation of singlet oxygen - Application in photocatalytic oxygenation
Mendoza Gallego, Carlos ULiege; Chateau, D.; Desert, Anthony et al

Conference (2018)

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit ... [more ▼]

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit intense and well-defined plasmon resonance, easily tunable with the aspect ratio and synergy between Au NPs and chromophores can enhance the photophysical properties of nearby molecules. In Rose Bengal (RB)-NPs systems for the production of singlet oxygen (1O2), it is now well established that the control of the dye-to-NP distance ranging from 10 to 20 nm is crucial to achieve the proper coupling between plasmon resonance and the dye1. We have developed AuBPs@mesoporous SiO2 core-shell nanostructures to control the distance between metallic surface and photosensitizers in order to increase the production of 1O2 through metal-enhanced fluorescence (MEF). An enhancement of 1O2 generation has been shown with the obtained anisotropic AuBPs and AuBPs@mSiO2 in presence of RB using different methods of 1O2 quantification. They are of interest to the application in photooxygenation reactions e.g. α-terpinene to ascaridole, an anthelmintic drug. [less ▲]

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See detailIntegrated continuous flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Lismont, Marjorie

Poster (2017, October 19)

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side ... [more ▼]

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side-reactions or product degradation due to overexposure. The recent implementation of photochemical processes in microreactors under continuous-flow conditions appeared to be much more powerful than its batch analogue in terms of irradiation efficiency and light penetration. Furthermore, the fine control of residence time ensures an accurate control of the irradiation time, avoiding side-reactions and degradation. The scalable photooxidation of (L)-methionine with singlet oxygen using Rose Bengal as a sensitizer was successfully implemented in a microreactor setup and led to total and selective conversion into methionine sulfoxide, an important building block for the organic synthesis of peptides or functionalized amino acid. The reaction was performed in less than 1 min while the same reaction in batch took 2 h. Other substrates as α-terpinene or citronellol were also photooxidized into high added value compounds using the same conditions. [less ▲]

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See detailSurface Modification of Powder Metallurgy Titanium by Colloidal Techniques and Diffusion Processes for Biomedical Applications
Ureña, Julia; Mendoza Gallego, Carlos ULiege; Ferrari, Begoña et al

in Advanced Engineering Materials (2017), 19(6),

This contribution focuses on modifying the composition and surface characteristics of powder metallurgy titanium substrates to improve their wear resistance and to reduce the surface Younǵs modulus, while ... [more ▼]

This contribution focuses on modifying the composition and surface characteristics of powder metallurgy titanium substrates to improve their wear resistance and to reduce the surface Younǵs modulus, while maintaining the corrosion resistance and biocompatibility. The modification consists of Mo and TiN coatings produced by colloidal techniques which are deposited by electrophoretic deposition (EPD) or spraying onto green or sintered titanium substrates. The final surface structures are formed during a heat treatment, during which diffusion and consolidation of the layers take place. The surfaces are characterised by XRD, SEM, and micro-indentation; showing diffusion areas of between 40 and 85 microns with clear microstructural changes as well as higher hardness values. [less ▲]

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See detailIntegrated continuous-flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Lismont, Marjorie et al

Poster (2017, March 31)

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side ... [more ▼]

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side-reactions or product degradation due to overexposure. The recent implementation of photochemical processes in microreactors under continuous-flow conditions appeared to be much more powerful than its batch analogue in terms of irradiation efficiency and light penetration. Furthermore, the fine control of residence time ensures an accurate control of the irradiation time, avoiding side-reactions and degradation. The photooxidation of (L)-methionine with singlet oxygen using Rose Bengal as a sensitizer was successfully implemented in a microreactor setup and led to total and selective conversion into methionine sulfoxide, an important building block for the organic synthesis of peptides or functionalized amino acid. The reaction was performed in 2 min while the same reaction in batch took 2 h. [less ▲]

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See detailScalable Photocatalytic Oxidation of Methionine under Continuous-Flow Conditions
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Winter, Marc et al

in Organic Process Research and Development (2017), 21

Highly efficient and chemoselective singlet oxygen oxidation of unprotected methionine was performed in water using a continuous mesofluidic reactor. Sustainable process engineering and conditions were ... [more ▼]

Highly efficient and chemoselective singlet oxygen oxidation of unprotected methionine was performed in water using a continuous mesofluidic reactor. Sustainable process engineering and conditions were combined to maximize process efficiency and atom-economy, with virtually no waste generation and safe operating conditions. Three water soluble metal-free photosensitizers (Rose Bengal, Methylene Blue, and tetrakis(4-carboxyphenyl)porphyrin) were assessed. The best results were obtained with Rose Bengal (0.1 mol%) at room temperature under white light irradiation and a slight excess of oxygen. Process and reaction parameters were monitored in real-time with in-line NMR. Other classical organic substrates (alpha-terpinene and citronellol) were oxidized under similar conditions with excellent performances. [less ▲]

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See detailIntegrated continuous flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Lismont, Marjorie ULiege et al

Poster (2016, December 08)

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side ... [more ▼]

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side-reactions or product degradation due to overexposure. The recent implementation of photochemical processes in microreactors under continuous-flow conditions appeared to be much more powerful than its batch analogue in terms of irradiation efficiency and light penetration. Furthermore, the fine control of residence time ensures an accurate control of the irradiation time, avoiding side-reactions and degradation. The photooxidation of (L)-methionine with singlet oxygen using Rose Bengal as a sensitizer was successfully implemented in a microreactor setup and led to total and selective conversion into methionine sulfoxide, an important building block for the organic synthesis of peptides or functionalized amino acid. The reaction was performed in 2 min while the same reaction in batch took 2h. [less ▲]

Detailed reference viewed: 61 (20 ULiège)