Article
Engineering, Environmental
Jinrong Yang, Weijie Chi, Wen-Jing Shi, Lei Zhang, Jin-Wu Yan
Summary: An in situ-triggered and chemi-excited photooxygenation system (Lf@6-3) was developed by designing and synthesizing a photosensitizer (BD-6-3) and loading it into mesoporous silica nanoparticles. The system could be activated by the high concentration of H2O2 in the pathological microenvironment of AD and produce singlet oxygen (1O2) to photooxygenate A beta aggregates, inhibiting their neurotoxic effect.
CHEMICAL ENGINEERING JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Ryota Matsukawa, Mina Yamane, Motomu Kanai
Summary: This review provides a thorough overview of the chemistry, resulting products, mechanisms, and analytical techniques involved in histidine photooxygenation. It explores the practical implications of this transformation in fields such as materials science, biomedical research, and drug development. By bridging the existing gap in literature, it serves as a resource for understanding the intricacies of histidine photooxygenation and its diverse ramifications.
Article
Chemistry, Multidisciplinary
Yanhai Ni, Wangjian Fang, Kim K. Baldridge, Mark A. Olson
Summary: Polycyclic aromatic endoperoxides are important sources of singlet oxygen (O-1(2)) and the photooxygenation of anthracene carboxyimides has not been reported due to their competing photodimerization reaction. This study describes the reversible photo-oxidation of anthracene carboxyimides, revealing the formation of racemic mixture of chiral hydroperoxides instead of the expected endoperoxide. The photoproduct undergoes photo- and thermolysis to form O-1(2). The anthracene carboxyimide also exhibits high selectivity and sensitivity for nitrite anions in acidic aqueous media and possesses stimuli-responsive behavior.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Hua-Qiao Tan, Zhen-Hui Kang, Yang-Guang Li, Tian-Yu Qiu, Ying-Nan Zhao, Wen-Si Tang, Hui-Ying Sun, Xia Zhao
Summary: To conveniently control photocatalytic reactions, the design and development of smart photocatalysts that can be regulated by external stimuli has attracted interest. In this study, a smart imine covalent-organic-framework (COF) photocatalyst was prepared and demonstrated to have switchable photocatalytic properties and efficient sulfide oxidation via proton-initiated reactions.
Article
Chemistry, Organic
Michael G. Kallitsakis, Dimitra K. Gioftsidou, Marina A. Tzani, Panagiotis A. Angaridis, Michael A. Terzidis, Ioannis N. Lykakis
Summary: The newly developed photocatalyst [Cu(Xantphos)(neoc)]BF4 can effectively oxygenate cycloalkenes into allylic hydroperoxides or alcohols with high yields and chemoselectivity. This methodology has been successfully applied to the synthesis of various bioactive compounds and perfumery ingredients, showcasing fast and clean reaction processes.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Jieqing Wu, Jiwei Chen, Lei Wang, Hongjun Zhu, Rui Liu, Guangliang Song, Chao Feng, Yufeng Li
Summary: This study presents a Bronsted acid-promoted aerobic photo-oxygenation method for the efficient synthesis of aromatic acids and ketones. It eliminates the need for transition metal complexes or organic photosensitizers, which increases its potential for industrial applications.
Article
Chemistry, Multidisciplinary
Nian Zhang, Sylvain Trepout, Hui Chen, Min-Hui Li
Summary: Biocatalytic transformation has gained attention for its diversity of enzymes, high catalytic activities, and environmentally friendly conditions. The combination of photocatalysts and enzymes using solar energy offers a green and efficient process, although the degradation of enzymes by reactive oxygen species (ROS) has been a challenge. This study presents the design of core-shell polymer micelles and vesicles as visible-light-mediated photocatalysts for stable and recyclable photobiocatalysis. The polymer colloids effectively regenerate the cofactor NAD+ from NADH while protecting the enzyme material from photogenerated ROS. These findings have potential applications in industrially relevant photobiocatalytic systems.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Engineering, Chemical
Mohsin Pasha, Yuhan Wang, Saier Liu, Guozhi Qian, Xiao Xue, Minjing Shang, Yuanhai Su
Summary: This study presents a highly efficient, chromoselective, and wavelength-selective high-power LED-based photomicroreactor (HLPMR) for multikilogram ascaridole production through solvent-free α-terpinene photooxidation. By implementing various operating schemes, kinetically controlled and mass transfer limited zones were segregated. The perfluoroalkoxy alkane (PFA) microchannel design configurations and volume were varied to increase the irradiated area and improve productivity, yield, and photochemical yield.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Paul De Bonfils, Elise Verron, Pierrick Nun, Vincent Coeffard
Summary: The study found that singlet oxygen release can be achieved through a thermolysis reaction, forming the 1,2-dihydropyridine compound.
Article
Chemistry, Multidisciplinary
Wenxin Wei, Francesca Mazzotta, Ingo Lieberwirth, Katharina Landfester, Calum T. J. Ferguson, Kai A. Zhang
Summary: By designing core-shell structured porous nano-photoreactors, highly stable and recyclable photobiocatalysis is achieved. The core efficiently regenerates the enzymatic cofactor, while the shell traps and deactivates photogenerated active oxygen species, protecting the enzymatic material.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Suting Xie, Xinyu Zhao, Dongxiao Wang, Huawei Yang, Lixia Yang, Liangjiu Bai, Donglei Wei, Wenxiang Wang, Ying Liang, Hou Chen, Shaojun Guo
Summary: Photocatalytic aerobic oxidation desulfurization (PAODS) is a sustainable alternative for desulfurization, but current photocatalysts have limitations in generating reactive oxygen species and sulfide oxidation rate. Researchers have developed a MoOx nanocluster decorated Mo-doped TiO2 catalyst that efficiently promotes the photocatalytic oxidation of sulfides, achieving a record oxidation activity.
SCIENCE CHINA-CHEMISTRY
(2023)
Article
Chemistry, Physical
Zhiming Ma, Shiqiang Liu, Nanfang Tang, Tao Song, Ken Motokura, Zhemin Shen, Yong Yang
Summary: The coexistence of Fe nanoclusters and Fe single atoms in N-doped porous carbon can significantly enhance the catalytic performance in the aerobic oxidation of primary amines to imines.
Review
Nanoscience & Nanotechnology
Mohsen Tamtaji, Abhishek Tyagi, Chae Young You, Patrick Ryan Galligan, Hongwei Liu, Zhenjing Liu, Rezvan Karimi, Yuting Cai, Alexander Perez Roxas, Hoilun Wong, Zhengtang Luo
Summary: Singlet oxygen (O-1(2)) is widely produced using nanostructure-based photocatalysts. Rational design of heterogeneous photocatalysts is crucial for achieving a high O-1(2) quantum yield. Various materials and strategies, such as graphene-based photocatalysts, are explored for light-driven O-1(2) sensitization, with potential applications in PDT, wastewater treatment, and photo-oxygenation reactions.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Organic
Louis Peault, Aurelien Planchat, Pierrick Nun, Erwan Le Grognec, Vincent Coeffard
Summary: The study presents a novel multiple-bond-forming process that combines singlet oxygen-mediated dearomatization with diastereo- and regioselective epoxidation, using a transition metal-free multicatalytic system. Mechanistic investigations have been conducted to elucidate the key species involved in this transformation. The method efficiently forms functionalized epoxyquinol products under mild conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Lamprini-Panagiota Apostolina, Artemis Bosveli, Antonia Profyllidou, Tamsyn Montagnon, Vasileios Tsopanakis, Maria Kaloumenou, Dimitris Kalaitzakis, Georgios Vassilikogiannakis
Summary: High value oxygenated polycycles can be rapidly and efficiently accessed from simple precursors using a new and mild method for butenolide synthesis mediated by thiols. The combination of initial photooxygenation and butenolide synthesis with subsequent photoredox reactions allows for rare dual-photocatalyst cascades, leading to fused butyrolactones and substituted cyclopentanones.
Article
Chemistry, Organic
Valeriia Hutskalova, Christof Sparr
Summary: The study explores the aryne-imine-aryne coupling reaction combined with acridane oxidation for the efficient synthesis of various acridinium salts. The photophysical properties of the novel photocatalysts were investigated and their practical value was demonstrated by a cation-radical accelerated nucleophilic aromatic substitution reaction.
Article
Chemistry, Multidisciplinary
Xingxing Wu, Christof Sparr
Summary: This paper describes the feasibility of an intramolecular Friedel-Crafts 6 pi electrocyclization, which is stereocontrolled by contact ion pairs. Through the use of a disulfonimide catalyst, enantioenriched acridinium tetrafluoroborate salts can be selectively synthesized.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Daniel Moser, Christof Sparr
Summary: Control over the configuration of multiple stereocenters is achieved simultaneously by using catalytic methods, providing a reliable basis for synthesizing stereochemically complex targets. By using cinchona alkaloid-based ion-pairing catalysts, it is possible to differentiate four feasible reaction pathways from identical substrates under defined basic conditions without preactivation, allowing for complete stereodivergence.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Markus Jakobi, Bouthayna Zilate, Christof Sparr
Summary: Photostability is crucial for the overall performance of photocatalysts. This article presents a modular and flexible synthetic approach to incorporate diarylamino moieties into organic acridinium photocatalysts, resulting in tunable redox behavior and enhanced photostability.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Tanno A. Schmidt, Stephan Schumann, Andreas Ostertag, Christof Sparr
Summary: In this study, we report the stereoselective synthesis of triptycyl sulfones with atropisomerism using a chiral phosphoric acid catalyst. The oxidation of a stereodynamic thioether controlled by the catalyst allowed selective access to enantioenriched triptycyl sulfoxides. Subsequent enantiospecific and diastereoselective catalytic oxidation resulted in overall control over the stereogenic C-S axis, with a stereoselectivity of up to (-sc): (+sc) : (ap)=94 : 6 :<1.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Nora Jannsen, Cornelia Pribbenow, Carmen Selle, Hans-Joachim Drexler, Marc-Andre Mueller, Jonathan A. Medlock, Werner Bonrath, Detlef Heller
Summary: An efficient and highly selective semi-hydrogenation of terminal alkynes to alkenes has been achieved using neutral dimeric rhodium(I) complexes. The results show excellent selectivity and no deactivation or reduction in selectivity, indicating the potential industrial application of homogeneous rhodium complexes in the semi-hydrogenation of terminal alkynes.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Daniel Moser, Kalipada Jana, Christof Sparr
Summary: In this study, the feasibility of atroposelective P-III/P-V=O redox organocatalysis by the Staudinger-aza-Wittig reaction is described. The formation of isoquinoline heterocycles allows for the synthesis of a wide range of valuable atropisomers with high enantioselectivities. The reaction is catalyzed by a chiral phosphine catalyst, with stereocontrol achieved through a silane reductant and Bronsted acid co-catalysis. The products can be easily transformed into N-oxides, naphthol, and triaryl phosphine variants, providing access to diverse aromatic heterocycles with precise control over their configuration.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Nora Jannsen, Cornelia Pribbenow, Carmen Selle, Ralf Jackstell, Hans-Joachim Drexler, Marc-Andre Muller, Jonathan A. Medlock, Werner Bonrath, Detlef Heller
Summary: The study successfully achieved the selective reduction of terminal alkynes to alkenes using specific rhodium catalysts. Although catalyst deactivation occurs at high concentrations, several strategies were proposed to overcome this deactivation.
Article
Chemistry, Physical
Tobias Vornholt, Zlatko Joncev, Valerio Sabatino, Sven Panke, Thomas R. Ward, Christof Sparr, Markus Jeschek
Summary: This study presents a biocatalytic strategy using artificial metalloenzymes for achieving atroposelective synthesis of binaphthalene compounds through ring-closing metathesis in aqueous media. It demonstrates that atroposelectivity can be fine-tuned by engineering amino acid residues within the streptavidin host protein. The resulting artificial metalloenzymes promote product formation with high enantiomeric ratios, and this approach offers an attractive and sustainable synthesis route for drug molecules and other compounds of interest.
Review
Chemistry, Medicinal
Anne-Cecile. Bayne, Zdravka Misic, Rehe T. Stemmler, Marc Wittner, Margarita Frerichs, Julia K. Bird, Ahmed Besheer
Summary: N-nitrosamines are potential carcinogens, and there has been a regulatory framework established for risk assessment, testing, and mitigation of these contaminants in drug products. One approach to prevent the formation of N-nitrosamines during drug manufacturing and storage is to incorporate nitrite scavengers into the formulation. Various molecules, including antioxidant vitamins, amino acids, and other antioxidants used in food or drugs, have been tested for their potential to mitigate N-nitrosamine formation in drug products. This review article provides a comprehensive overview of key considerations for incorporating nitrite scavengers in oral drug formulations.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2023)
Article
Chemistry, Organic
Valeriia Hutskalova, Farhan Bou Hamdan, Christof Sparr
Summary: An efficient methodology for the photoredox- and nickel-catalyzed aminocarbonylation of (hetero)aryl bromides was developed using readily available oxamic acids and a widely used organic photoredox catalyst. This transformation provides an attractive alternative to classical amidation procedures, with mild reaction conditions.
Review
Chemistry, Applied
Werner Bonrath, Bo Gao, Peter Houston, Tom McClymont, Marc-Andrei Mu''ller, Christian Scha''fer, Christiane Schweiggert, Jan Schu''tz, Jonathan A. Medlock
Summary: In 1948, F. Hoffmann-La Roche successfully produced the first kilograms of synthetic vitamin A (acetate), eliminating the need for extraction from natural sources. This marked 75 years of successful production. Various chemical routes have been commercialized since then, with three processes standing the test of time. This review discusses both the historical and scientific developments in the production of vitamin A derivatives, including recent developments such as a fully catalytic process and successful pilot-scale production via fermentation. The development of formulation technologies, essential for stabilizing light and oxidation-sensitive vitamin A derivatives, is also described.
ORGANIC PROCESS RESEARCH & DEVELOPMENT
(2023)
Article
Chemistry, Multidisciplinary
Daniel Moser, Tanno A. Schmidt, Christof Sparr
Summary: This Perspective discusses the benefits and challenges of catalyst-controlled diastereodivergence in constructing carbon stereocenters, and extends these concepts to diastereodivergent catalysis for atropisomeric systems and E- and Z-configured alkenes.
Article
Chemistry, Multidisciplinary
Bjorn Pfund, Valeriia Hutskalova, Christof Sparr, Oliver S. Wenger
Summary: By modifying acridinium dyes, a new family of organic photocatalysts called isoacridones was obtained, which have both photoactive singlet- and triplet-excited states. These isoacridone dyes have high intersystem crossing efficiencies and can store significant amounts of energy. They can be used for parallel triplet-triplet energy transfer and photoinduced electron transfer, making them suitable for modern photocatalysis. In proof-of-principle experiments, the isoacridone dyes demonstrated their potential for applications such as arene reductions and C-C couplings. Additionally, by combining with an annihilator, sensitized triplet-triplet annihilation upconversion was achieved.
Article
Chemistry, Multidisciplinary
Kevinjeorjios Pellumbi, Leon Wickert, Julian T. Kleinhaus, Jonas Wolf, Allison Leonard, David Tetzlaff, Roman Goy, Jonathan A. Medlock, Kai Junge Puring, Rui Cao, Daniel Siegmund, Ulf-Peter Apfel
Summary: Electrosynthetic methods are crucial for the sustainable transformation of the chemical industry. This study discovered the promising activity of transition metal pentlandites as catalysts in electrochemical hydrogenation reactions, achieving high current densities, high Faraday efficiencies, and high alkene selectivity in the hydrogenation of alkynols. The successful integration of a sustainable catalyst into a scalable zero-gap electrolyser establishes the foundation for the practical application of electrosynthetic methods.
