Article
Chemistry, Organic
Sandip Bag, Shubham Ojha, Sreelakshmi Venugopalan, Basudev Sahoo
Summary: In this study, we present a visible-light photoredox-catalyzed alkylation/arylative cyclization reaction of N-acrylamides with ketone-derived dihydroquinazolinones. This method allows the formation of indolo- and benzimidazolo[2,1-a]isoquinolines or 2-oxindoles from 2-arylindoles, 2-arylbenzimidazoles, or N-substituted anilines. The reaction proceeds through the formal cleavage of ketone α-C-C and arene C-H bonds, leading to the incorporation of alkyl and aryl carbogenic motifs and the synthesis of cyclic structures with a quaternary stereocenter.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Chada Raji Reddy, Dattahari H. Kolgave, Uprety Ajaykumar, Remya Ramesh
Summary: A copper-catalyzed ipso-annulation reaction of N-(p-methoxyaryl)propiolamides with 1,3-diketones has been developed, enabling the synthesis of diketoalkylated spiro[4.5]trienones and spiro[5.5]trienones.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Uwe Osswald, Johannes Boneberg, Valentin Wittmann
Summary: Multivalent receptor-ligand binding is crucial in biological recognition processes. The incorporation of photoswitches into multivalent ligands enables the reversible change of spatial orientation, resulting in altered binding affinity and mode. This study presents a divalent ligand for wheat germ agglutinin (WGA) with an arylazopyrazole photoswitch, showing significant changes in lectin binding affinity and mode.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Franz-Lucas Haut, Riccardo S. Mega, Joan V. Estornell, Ruben Martin
Summary: We describe a catalytic intramolecular decarboxylative/desulfonylative sp(3) allylation triggered by sulfinate salts under light irradiation. The reaction likely proceeds through a non-classical, radical-polar crossover mechanism, providing a rapid and reliable method to access valuable allyl architectures from readily available precursors. The protocol is characterized by its simplicity, scalability, and the use of abundant, commercially available catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Alessandro Marotta, Hao Fang, Callum E. Adams, Kailey Sun Marcus, Constantin G. Daniliuc, John J. Molloy
Summary: Operationally simple strategies using visible light and a simple Lewis base are disclosed for the facile activation of α-halo boronic esters, leading to the construction of versatile E-allylic boronic esters via intermolecular addition to styrenes. This activation method can be strategically merged with selective energy transfer catalysis for the complimentary stereodivergent synthesis of Z-allylic boronic esters.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Zexian Li, Minyan Wang, Zhuangzhi Shi
Summary: An efficient method for photocatalytic perfluoroalkylation of vinyl-substituted all-carbon quaternary centers involving 1,2-aryl migration has been developed, generating valuable multisubstituted perfluoroalkylated compounds in a single step. Mechanistically, photoinduced alkyl radical addition to an alkene leads to migration of a vicinal aryl substituent from its adjacent all-carbon quaternary center, followed by generation of a C-radical bearing two electron-withdrawing groups and reduction by a hydrogen donor to complete the domino sequence.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Kosaku Tanaka, Mayumi Yoshida, Ayaka Yamamoto, Yoshimitsu Hashimoto, Nobuyoshi Morita, Osamu Tamura
Summary: Oximes undergo photo-promoted, copper-catalyzed N-selective arylation with diaryl iodonium salts to produce nitrones, which further undergo intra- or intermolecular 1,3-dipolar cyclization with olefins to form N-aryl isoxazolidines. The reaction proceeds via a radical/single electron transfer (SET) pathway and requires photoirradiation for activation.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Hongchao Yin, Yuan Tian, Chenxi Guo, Ran Song, Daoshan Yang, Jian Lv
Summary: A facile tandem oxa-Nazarov cyclization and dibromination has been developed, in which the combination of Cu(OTf)2 and diphenyl phosphate (DPP-H) synergistically promotes the coupling of conjugated 1,2-diketones and N-bromosuccinimide, leading to the formation of 2,4-dibromo-3(2H)-furanones in good yields.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Maximilian Scheruebl, Constantin G. Daniliuc, Armido Studer
Summary: The article introduces the application of arynes as radical acceptors, showing how the stable radical TEMPO can react with different ortho-substituted benzynes to generate aryl radicals for subsequent cyclizations, eventually being trapped by TEMPO. This method provides a novel approach for the convenient synthesis of various dihydrobenzofurans, oxindoles, and sultones.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Engineering, Environmental
Min Xie, Chengyang Zhang, Hongcen Zheng, Guoyang Zhang, Shujuan Zhang
Summary: This study investigated the effects of diketones (AcAc and BD) on the photochemical conversion of CBZ, compared with H2O2. The results showed that adding diketones enhanced the degradation of CBZ, particularly under simulated solar irradiation. Organic peroxyl radicals were found to play a dominant role in CBZ photodegradation. Furthermore, mutagenic acridine was identified as a major cumulative intermediate in the presence of diketones.
Article
Chemistry, Multidisciplinary
Remi Canterel, Jacques Lalevee, Elodie Bourgeat-Lami, Emmanuel Lacote, Muriel Lansalot
Summary: Polystyrene particles were successfully synthesized in a mixture of ethanol and water using visible light and an optimized photoinitiating system. The addition of a base and the use of a specific stabilizer significantly improved the reproducibility and allowed for the formation of larger, narrowly distributed particles.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Zhenda Tan, Shibo Zhu, Yangbin Liu, Xiaoming Feng
Summary: This article reports a photoinduced chemo-, site- and stereoselective alpha-C(sp(3))-H functionalization of sulfides using isatins as the photoredox reagent and coupling partner catalyzed by a chiral gallium(III)-N,N '-dioxide complex. The reaction proceeds through a verified single-electron transfer (SET) mechanism with high efficiency, excellent functional group tolerance, as well as a broad substrate scope. Importantly, this cross-coupling protocol is highly selective for the direct late-stage functionalization of methionine-related peptides, regardless of the inherent structural similarity and complexity of diverse residues.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Youkang Zhou, Lirong Zhao, Mingyou Hu, Xin-Hua Duan, Le Liu
Summary: In this study, a photoredox-catalyzed divergent 1,2-dicarbonylation and hydroacylation of alkenes with acid anhydride was presented. This approach provides a mild and efficient method for synthesizing 1,4-dicarbonyl compounds bearing all-carbon quaternary centers, demonstrating a broad substrate scope and high functional group compatibility. Hydrocarbonylation of alkenes can also be achieved by introducing a proton source to the reaction system. Mechanistic investigations support a radical addition/radical-polar crossover cascade.
Article
Chemistry, Multidisciplinary
Qiang Liu, Bei-Bei Zhang, He Sheng, Sen Qiao, Zhi-Xiang Wang, Xiang-Yu Chen
Summary: The visible-light-induced photoreduction of carborane phosphonium salts under blue light irradiation provides a simple and effective method for accessing carbon-centered carboranyl radicals without the use of transition metals and photocatalysts. The utility of this method is demonstrated by the successful preparation of carborane-oxindole-pharmaceutical hybrids through radical cascade reactions. Computational and experimental studies suggest that the carbon-centered carboranyl radicals are generated through single-electron transfer of photoactive charge-transfer complexes between the salts and the additive potassium acetate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
D. Sai Reddy, Ivan M. Novitskiy, Andrei G. Kutateladze
Summary: A novel photoinduced cascade reaction has been developed to access complex nitrogen polyheterocycles. This reaction involves excited state intramolecular proton transfer in aromatic amino ketones with tethered dual unsaturated pendants, leading to the formation of four sigma bonds and setting six new stereogenic centers in a single photochemical step with significant complexity increases of up to 220 mcbit.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Dimitri Alvarez Dorta, David Deniaud, Mathieu Mevel, Sebastien G. Gouin
CHEMISTRY-A EUROPEAN JOURNAL
(2020)
Article
Electrochemistry
Ranil C. T. Temgoua, Ugo Bussy, Dimitri Alvarez-Dorta, Nicolas Galland, Julie Hemez, Ignas K. Tonle, Mohammed Boujtita
ELECTROCHIMICA ACTA
(2020)
Article
Chemistry, Multidisciplinary
Coralie Assailly, Clarisse Bridot, Amelie Saumonneau, Paul Lottin, Benoit Roubinet, Eva-Maria Krammer, Francesca Francois, Federica Vena, Ludovic Landemarre, Dimitri Alvarez Dorta, David Deniaud, Cyrille Grandjean, Charles Tellier, Sagrario Pascual, Veronique Montembault, Laurent Fontaine, Franck Daligault, Julie Bouckaert, Sebastien G. Gouin
Summary: In this study, researchers developed multi- and polyvalent compounds capable of inhibiting bacterial sialidases. These compounds show a higher inhibitory potential than monovalent analogues, and exhibit a synergistic interaction in the catalytic domain. These results offer interesting perspectives for multivalent inhibition of other SA families lacking a carbohydrate-binding module.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Analytical
Ranil C. T. Temgoua, Ugo Bussy, Dimitri Alvarez-Dorta, Nicolas Galland, Julie Hemez, Christine Thobie-Gautier, Ignas Kenfack Tonle, Mohammed Boujtita
Summary: The study focuses on the electrochemical behavior/degradation of the carbendazim (CBZ) fungicide, with the use of EC-LC-MS and EC-MS analysis to identify new degradation products such as a quinone imine and a nitrenium ion. This hyphenated technique proved to be a rapid and reliable tool to elucidate the oxidative degradation of CBZ.
Article
Chemistry, Organic
Elisa Leon, Angeles Martin, Adrian S. Montes, Ines Perez-Martin, Maria del Sol Rodriguez, Ernesto Suarez
Summary: The study investigates a radical/polar sequence triggered by alkoxyl radicals in 1,5-HAT-1,2-(ester)alkyl radical migration, leading to the efficient construction of complex carbohydrate frameworks. Attention was given to the influence of stereochemistry on the reaction outcome. The addition of BF3·Et2O catalyst significantly increased the yields of desired bicyclic ketals.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Adrian S. Montes, Elisa Leon, Angeles Martin, Ines Perez-Martin, Ernesto Suarez
Summary: A simple method for the epimerization of C-(alpha-d-Glyp)methanol into C-(beta-l-Glyp)methanol compounds is described in this study. The reaction involves radical cleavage of the C5-H bond by 1,5-hydrogen atom transfer followed by hydride addition with inversion of configuration. This methodology allows the synthesis of rare C-(beta-l-Idop)-, C-(beta-l-Altp)-, C-(beta-l-Gulp)-, C-(beta-l-Allp)methanol glycosides starting from d-series carbohydrates. It can also be used to transform l-configured C-glycosyl compounds to d-configured ones. The synthesis of C-(beta-d-6dGulp)- and C-(beta-d-6dAltp)methanol from readily accessible l-rhamno and l-fuco analogs, respectively, demonstrates the applicability of this method. Furthermore, compounds with C-(beta-l-Araf)- and C-(beta-l-5dRibf)methanol structures have also been synthesized. The influence of sugar ring conformation and substituent electronegativity on the stereochemical outcome is discussed based on experimental results.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Dimitri Alvarez-Dorta, Elisa Leon, Angeles Martin, Alan R. Kennedy, Ines Perez-Martin, Kenneth Shankland, Ernesto Suarez
Summary: The research shows that the regioselectivity of the Norrish-Yang type II photocyclization dramatically increases in the crystalline state of both polymorphs of 3 beta-acetoxy-16,17-seco-17,20-dioxopregn-5-ene-16-nitrile. X-ray crystallography and molecular mechanics calculations reveal crystal structure-solid state photochemistry relationships.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Sebastien Depienne, Dimitri Alvarez-Dorta, Mikael Croyal, Ranil C. T. Temgoua, Cathy Charlier, David Deniaud, Mathieu Mevel, Mohammed Boujtita, Sebastien G. Gouin
Summary: This study evaluated the limitations, benefits, and relative efficiencies of eY-click conjugations using PhUr, NMePhUr, and NMeLum derivatives. NMeLum demonstrated high efficiency and complete Y-chemoselectivity on polypeptides and biologically relevant proteins after soft electrochemical activation. Side reactions on nucleophilic or heteroaromatic amino acids were never observed during mass spectrometry analysis.
Article
Chemistry, Analytical
Ranil Clement Tonleu Temgoua, Ugo Bussy, Dimitri Alvarez-Dorta, Nicolas Galland, Evangeline Njanja, Julie Hemez, Christine Thobie-Gautier, Ignas Kenfack Tonle, Mohammed Boujtita
Summary: In this study, an alternative non-enzymatic method using electrochemistry coupled to liquid chromatography-high resolution mass spectrometry-DFT theoretical calculations was proposed for simulating the environmental degradation of phenylurea herbicides and elucidating their mechanism. The main oxidation products were hydroxylated compounds obtained by substitution and addition reactions. This method successfully mimicked various reactions and provided useful insights for understanding and predicting the oxidative degradation pathways of pesticides in the environment.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2021)
