Article
Chemistry, Organic
Raquel Perez-Guevara, Luis A. A. Sarandeses, M. Montserrat Martinez, Jose Perez Sestelo
Summary: A novel indium-catalyzed synthesis of benzannulated spiroketals is reported in this study. The reaction proceeds under mild conditions using a low catalyst loading of indium triiodide, and produces a series of benzannulated spiroketals in good yields. The method involves indium(iii)-catalyzed electrophilic alkyne activation followed by regioselective intramolecular hydroalkoxylation reaction, representing an economical alternative to precious transition metals and providing a complementary strategy for the selective synthesis of spiroketals.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Multidisciplinary Sciences
Clement Jacob, Hajar Baguia, Amaury Dubart, Samuel Oger, Pierre Thilmany, Jerome Beaudelot, Christopher Deldaele, Stefano Perusko, Yohann Landrain, Bastien Michelet, Samuel Neale, Eugenie Romero, Cecile Moucheron, Veronique Van Speybroeck, Cedric Theunissen, Gwilherm Evano
Summary: This study reports a general anti-Baldwin radical 4-exo-dig cyclization from nitrogen-substituted alkynes. Under visible light irradiation in the presence of a heteroleptic copper complex and an amine, a range of ynamides smoothly cyclize to the corresponding azetidines. The cyclization reaction shows full control of the regioselectivity, allowing the synthesis of useful building blocks in natural product synthesis and medicinal chemistry.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Yu-Jiao Chen, Liang-Tao Wu, Tai-An Li, Meng-Qin Pu, Xiao-Li Sun, Hongli Bao, Wen-Ming Wan
Summary: A novel Ketyl Mediated Polymerization (KMP) is developed by introducing ketyl radical anion species, which enables radical polymerization at the carbon radical site and anionic ring-opening polymerization at the oxygen anion site. Through KMP, organic synthesis and polymerization can be achieved simultaneously in one pot, resulting in the successful preparation of small molecules and polymers with low molecular weight distribution. This work expands the reaction mode and method libraries of organic chemistry and polymer chemistry, saving time, labor, resources, and energy.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Materials Science, Multidisciplinary
Hiroki Ito, Akinori Takasu, Masahiro Higuchi
Summary: The pairing of tri-n-butyl phosphine and methylaluminum bis(2,6-di-tert-butyl-4-methyl-phenoxide) acts as a frustrated Lewis pair for the controlled anionic polymerization of ethyl sorbate. The use of dimethyl-phenylphosphine as the initiator enables the anionic polymerization of ethyl sorbate in toluene, with ring closure occurring at a higher temperature without the need for highly dilute conditions. This method allows for the synthesis of cyclic vinyl polymers using phosphine instead of expensive N-heterocyclic carbenes, expanding the research range of cyclic polymer science.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Chemistry, Organic
Qiang Zhang, Xiaojuan Li, Weigang Zhang, Yi Wang, Yi Pan
Summary: This work presents a sequential radical difunctionalization strategy for constructing fluorine-containing vinylboronates and alkylboronates using the integrated redox-active reagent N-trifluoromethylthiophthali-mide. This method offers a scalable and practical protocol for trifluoromethylthiolation-borylation of unsaturated hydrocarbons in a highly regio- and stereoselective manner, which can be further converted into valuable synthons through boryl migration.
Article
Chemistry, Organic
Yu Liu, Tengfei Pang, Weijun Yao, Fangrui Zhong, Guojiao Wu
Summary: A visible-light-induced radical gem-iodoallylation reaction was developed for the synthesis of alpha-CF3-substituted homoallylic iodide compounds from CF3CHN2. The reaction showed broad substrate scope, good compatibility with functional groups, and operational simplicity. This protocol provides a convenient and attractive tool for the introduction of CF3 group in radical synthetic chemistry.
Article
Biochemistry & Molecular Biology
Hongqiang Dong, Chunli Chen, Jinlei Zhao, Yigang Ji, Wenchao Yang
Summary: The focus of this investigation is a novel approach to synthesize sulfonylated heterocycles, which addresses the limitations of conventional methods by using an affordable sulfonylating agent and operating under metal-free and photocatalyst-free conditions.
Article
Chemistry, Multidisciplinary
Jiajia Yu, Xu Zhang, Xinxin Wu, Tao Liu, Zhi-Qi Zhang, Jie Wu, Chen Zhu
Summary: Due to its simplicity, ethylene, as the most abundant organic feedstock, has limited applications in fine chemical synthesis, leading to the formation of molecules with modest complexity. Ethylene difunctionalization allows for the synthesis of more complex chemicals, but it is rare and typically relies on transition-metal catalysis. In this study, a novel metal-free radical difunctionalization of ethylene through functional group migration strategy is reported. The use of sulfone-based bifunctional reagents enables straightforward access to a wide range of diheteroarylated compounds under mild conditions in a highly selective manner, facilitated by the precise modulation of radical polarity and kinetic preference arising from intramolecular functional group migration.
Article
Chemistry, Multidisciplinary
Seonghun Park, Juhyung Lee, Hwakyeung Jeong, Sangeun Bae, Joongoo Kang, Dohyun Moon, Jinhee Park
Summary: Understanding the dynamic structural changes accompanying radical formation provides detailed insights into the design of stimuli-responsive redox-active materials. In this study, a metal-organic framework (MOF) was developed, and the reduction of NDI moieties to the radical-anionic state was triggered by various stimuli, revealing multiple electron transfer pathways guided by structure.
Article
Chemistry, Multidisciplinary
Kensuke Suzuki, Naoki Sugihara, Yoshihiro Nishimoto, Makoto Yasuda
Summary: We have achieved the first anti-borylstannylation of alkynes by using (o-phenylenediaminato)borylstannanes. This reaction provides 1-boryl-2-stannylalkenes with excellent regio- and stereoselectivity through a radical mechanism. The mild reaction conditions allow for a wide range of substrates, and the products can be further used in cross- or homocoupling reactions to synthesize important compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Zhenfeng Cheng, Xiaodong Qiu, Biao Xiong, Yanan Zhang, Xiaobao Zeng
Summary: This study presents a TMSCN-enabled tandem reaction involving enamides and elemental selenium to access a diverse array of benzoselenophenes. The protocol offers several noteworthy features, including the absence of transition metals and strong oxidants, high reaction efficiency, broad substrate scopes, and the use of stable elemental selenium as a selenium source.
Article
Chemistry, Multidisciplinary
Martin Piesch, Stephan Reichl, Michael Seidl, Gabor Balazs, Manfred Scheer
Summary: A synthetic pathway was developed for the synthesis of novel anionic sandwich complexes with cyclo-E-3 (E=P, As) ligands, which were further utilized to obtain various types of complexes. The reaction pathway was elucidated using DFT calculations, leading to the successful isolation of heteroatomic complexes with unique structures.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Nantachai Inprung, Hon Eong Ho, James A. Rossi-Ashton, Ryan G. Epton, Adrian C. Whitwood, Jason M. Lynam, Richard J. K. Taylor, Michael J. James, William P. Unsworth
Summary: Indole-ynones have been established as versatile substrates for radical dearomatizing spirocyclization cascade reactions, and five different synthetic protocols have been developed. These simple and readily available compounds can rapidly generate diverse, densely functionalized spirocycles and offer new avenues for exploring radical reactivity.
Article
Polymer Science
Akhil Dev, Alexander Roesler, Helmut Schlaad
Summary: The acyclic monoterpene beta-myrcene is polymerized by anionic polymerization using sec-butyllithium as the initiator and DL-limonene as a solvent at room temperature. The polymerization process is living, producing polymyrcenes with narrow molar mass distribution and high content of 1,4 units, as well as block copolymers.
Article
Chemistry, Organic
Fuyu Xie, Jianghua He, Yuetao Zhang
Summary: This article presents a strategy for generating Frustrated radical pairs (FRP) using a Lewis acid and a Lewis base. The FRP can efficiently initiate atom-transfer radical addition (ATRA) reactions, resulting in high regioselectivity and high yields of fluoroalkylated compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
V. A. Balycheva, A. Ya Akyeva, E. A. Saverina, P. G. Shangin, I. Krylova, V. A. Korolev, M. P. Egorov, I. Alabugin, M. A. Syroeshkin
Summary: This study investigated the electroreduction of 4-phenyl-1,2,4-triazoline-3,5-dione under aprotic conditions and elucidated the reaction mechanism. The results showed that a chain reaction occurred during the reduction process, leading to the formation of triazolo[1,2-a]triazole-1,3,5,7-tetraone. Cyclic voltammetry was employed to analyze the detailed mechanism of this reaction.
RUSSIAN CHEMICAL BULLETIN
(2022)
Editorial Material
Chemistry, Physical
Lena Kersting, Leah Kuhn, Maksim Anokhin, Florian Schuster, Cecile Haberli, Shainy Sambyal, Halmuthur M. Sampath Kumar, Jennifer Keiser, Igor Alabugin, Svetlana B. Tsogoeva
Summary: An efficient metal-free visible-light-driven two-step domino reaction has been developed for synthesizing new bioactive compounds. The combination of fluorescein and thiourea proved to be the most effective promoter, with yields up to 97% and a broad substrate scope. Experimental and computational evidence supported the role of singlet oxygen in the reaction, and thiourea acted as an electron-transfer mediator and/or scavenger of reactive oxygen species. Furthermore, in vitro studies showed high antischistosomal and anti-cancer activities of the tetrahydroisoquinoline-butenolide hybrid compounds.
Article
Chemistry, Physical
Sumesh B. Krishnan, Ronald J. Clark, Xinsong Lin, Olga Dmitrenko, Edwin F. Hilinski, Leah R. Kuhn, Igor V. Alabugin, Jack Saltiel
Summary: This article discusses the differences in photochemical and photo-physical behavior between trans-alpha-methylstilbene and trans-stilbene, and presents their X-ray structures. The study found that methyl substitution leads to molecular nonplanarity and structural changes, which affect the lifetime of the trans excited states and the fluorescence quantum yield. Additionally, these findings are relevant to chirality issues in biological molecules.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Organic
Quintin Elliott, Igor V. Alabugin
Summary: AIBN is a convenient electrophilic cyanation reagent that can convert ArLi into ArCN under mild conditions. The addition/fragmentation cascade is controlled by Li...N chelation, with AIBN nitrogens assisting in the nearly barrierless fragmentation into the desired ArCN product. Acidic C-H bonds in the fragmented byproduct consume ArLi through protonation. Density functional theory calculations and isotopic labeling were used to study the mechanism and explain the switch to substituted hydrazones in reactions with BuLi.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Almir. S. S. Gazizov, Andrey. V. V. Smolobochkin, Tanzilya. S. S. Rizbayeva, Sergey. Z. Z. Vatsadze, Alexander. R. R. Burilov, Oleg. G. G. Sinyashin, Igor. V. V. Alabugin
Summary: Ureas are often considered to have similar reactivity as amides due to their structural similarity, but they can exhibit distinct differences in reactivity. Rotation of ureas can switch off the amide resonance and recover the nucleophilicity of one of the nitrogen atoms. This change in reactivity is an example of stereoelectronic deprotection and can be used for the synthesis of unusual compounds.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Vera A. Vil', Yana A. Barsegyan, Leah Kuhn, Alexander O. Terent'ev, Igor V. Alabugin
Summary: The reaction of Ni(II) acetate with diacyl peroxides produces high-valence Ni-species capable of catalytic oxidative acyloxylation of C(sp3)-H bonds in ethers, ketones, and alkanes. The desired esters were obtained in 20-82% yields. Computational and experimental analyses revealed various viable C-H activation patterns, with the spirocyclopropyl moiety playing a crucial role in preventing premature radical decarboxylation.
Review
Chemistry, Multidisciplinary
Chaowei Hu, Justice Mena, Igor V. V. Alabugin
Summary: The alkyne is a versatile organic functional group that can undergo cascade transformations to add up to three new bonds to each of its carbon atoms. However, the strong kinetic protection provided by p-orbital overlap makes the design of new alkyne transformations challenging, especially on multifunctional substrates. This Review explores the electronic properties of alkynes in radical cascades and discusses methods to control their selectivity and reactive intermediates to achieve diverse product outcomes.
NATURE REVIEWS CHEMISTRY
(2023)
Article
Chemistry, Applied
Ivan A. Yaremenko, Yulia Yu. Belyakova, Arina A. Demina, Peter S. Radulov, Igor V. Alabugin, Alexander O. Terent'ev
Summary: A selective reaction between bridged ozonides and Fe(II) salts has been found to proceed through O-O and C-C scissions and halogenation, leading to the formation of alpha-halogen substituted delta-ketoesters and delta-diketones in yields of 15-72%. This overall sequence demonstrates how a temporary peroxide functionality can be used to replace the acyl group within an acetoacetic ester unit with a halogen.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Biochemistry & Molecular Biology
Andrei V. Bogdanov, Margarita Neganova, Alexandra Voloshina, Anna Lyubina, Syumbelya Amerhanova, Igor A. Litvinov, Olga Tsivileva, Nurgali Akylbekov, Rakhmetulla Zhapparbergenov, Zulfiia Valiullina, Alexandr V. Samorodov, Igor Alabugin
Summary: A series of new fluorinated isatins were synthesized via a simple one-pot procedure. These new isatins exhibit antitumor activity, anti-aggregation activity, and antagonistic effect against plant pathogens.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Elmira Gibadullina, Margarita Neganova, Yulia Aleksandrova, Hoang Bao Tran Nguyen, Alexandra Voloshina, Mikhail Khrizanforov, Thi Thu Nguyen, Ekaterina Vinyukova, Konstantin Volcho, Dmitry Tsypyshev, Anna Lyubina, Syumbelya Amerhanova, Anna Strelnik, Julia Voronina, Daut Islamov, Rakhmetulla Zhapparbergenov, Nurbol Appazov, Beauty Chabuka, Kimberley Christopher, Alexander Burilov, Nariman Salakhutdinov, Oleg Sinyashin, Igor Alabugin
Summary: This study explores the biological activity of a family of new hybrid molecules that combine sterically hindered phenols (SHPs) with additional urea/thiourea fragments. It finds that these compounds exhibit cytotoxic activity against tumor cells and have dual properties of pronounced antioxidant activity and increased reactive oxygen species generation. Molecular docking analysis reveals a potential target for these compounds. The most promising compounds can induce apoptosis in cancer cells through the intrinsic mitochondrial pathway.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Organic
Ivan A. Yaremenko, Yulia Yu. Belyakova, Peter S. Radulov, Michael G. Medvedev, Nikolai V. Krivoshchapov, Igor V. Alabugin, Alexander O. Terent'ev
Summary: The relief of stereoelectronic frustration drives the acid-catalyzed three-component condensation, allowing the preparation of otherwise inaccessible compounds rapidly and selectively.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Beauty K. Chabuka, Igor V. Alabugin
Summary: In order to use holes as catalysts, the oxidation potential along the reaction path must increase, leading to hole upconversion. This study provides guidelines for the rational design of hole-catalyzed Diels-Alder (DA) reactions. The occurrence and magnitude of hole upconversion depend strongly on the placement and nature of substituents in the reactants, and stereoelectronic effects can activate or deactivate upconversion via conformational changes.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Elena Chugunova, Almir S. Gazizov, Daut Islamov, Victoria Matveeva, Alexander Burilov, Nurgali Akylbekov, Alexey Dobrynin, Rakhmetulla Zhapparbergenov, Nurbol Appazov, Beauty K. Chabuka, Kimberley Christopher, Daria I. Tonkoglazova, Igor V. Alabugin
Summary: This study reports an unusual transformation in which the transient formation of a nitrene moiety initiates a sequence of steps leading to remote oxidative C-H functionalization and nitrene reduction into an amino group. No external oxidants or reductants are required for this process, and detected intermediates and computational analysis suggest the involvement of pyrazole ring opening and recyclization.
Article
Biochemistry & Molecular Biology
Adam Campbell, Nikolas R. Dos Santos, Igor Alabugin
Summary: We utilized a cycloaromatization reaction to photouncage aldehydes and ketones by relieving excited state antiaromaticity. Several synthetic routes were developed to prepare photocaged carbonyls as allylically substituted 3-(2-(arylethynyl)phenyl)prop-2-en-1-ols. A library of photocaged aryl aldehydes and ketones was synthesized, including those with donors and acceptors, fragrances, and the steroid 5α-cholestan-3-one, showing good to excellent photouncaging yields.
Article
Chemistry, Multidisciplinary
Beauty K. Chabuka, Igor V. Alabugin
Summary: To use holes as catalysts, the oxidation potential along the reaction path must increase, leading to hole upconversion. This study provides guidelines for the rational design of hole-catalyzed Diels-Alder reactions by evaluating the effects of substituents on the occurrence and magnitude of hole upconversion. Stereoelectronic effects can also activate or deactivate upconversion via a conformational change.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)