Article
Chemistry, Organic
Prasoon Raj Singh, Pratibha Kalaramna, Shamsad Ali, Avijit Goswami
Summary: A simple protocol has been developed to access thio-/selenopyrrolines through a (3+2)-cycloaddition reaction using SnCl4 as a Lewis acid catalyst. Good chemoselectivity was observed when DACs were treated, indicating that thiocyanate is more reactive than nitrile moiety in such reactions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Grzegorz Mloston, Mateusz Kowalczyk, Andre U. Augustin, Peter G. Jones, Daniel B. Werz
Summary: The reactivity of donor-acceptor cyclopropanes towards thioketenes was investigated, leading to the formation of exocyclic thioenol ethers in moderate to good yields in a (3+2)-cycloaddition using Sc(OTf)(3) as a Lewis acidic catalyst. Unsymmetrical thioketenes provided E/Z mixtures at the double bond, with the Z isomer being preferred.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Yong Xia, Xiaohua Liu, Xiaoming Feng
Summary: The donor-acceptor (D-A) cyclopropanes, due to the synergistic push-pull effect of vicinal electron-donating and electron-withdrawing groups, are recognized as powerful building blocks for generating polyfunctional reactive intermediates. Enantioselective reactions of D-A cyclopropanes provide an efficient approach to enantioenriched acyclic and cyclic compounds. Chiral Lewis/Bronsted acids, transition metals, and organocatalysts have been designed for such transformations, including ring-openings, annulations, and rearrangements.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Nils L. Ahlburg, Oliver Hergert, Peter G. Jones, Daniel B. Werz
Summary: A novel class of highly activated donor-acceptor cyclopropanes with a single vinylogous acceptor is presented. These moieties undergo cycloaddition reactions with various substrates to form carbo- and heterocycles. The stereochemical outcome can be controlled by the choice of catalyst. Mechanistic and kinetic experiments were conducted to explain the catalytic cycle and stereoselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Stefano Nicolai, Jerome Waser
Summary: This study reports a Lewis acid catalyzed (4+3) annulative addition reaction for the efficient synthesis of densely substituted azepanes. The reaction achieved good yields and high diastereoselectivity under mild conditions using ytterbium triflate or copper triflate with a trisoxazoline ligand as the catalyst. The obtained cycloadducts were convenient substrates for further modifications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Nils L. Ahlburg, Tyll Freese, Simon Kolb, Sebastian Mummel, Andreas Schmidt, Daniel B. Werz
Summary: The paper describes a rare, low-temperature, transition metal-free, and functional group tolerant protocol for the late-stage functionalization of mesoionic compounds, which are emerging as important in catalysis and bio-orthogonal chemistry.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
David A. McLeod, Mathias Kirk Thogersen, Casper Larsen Barlose, Mette Louise Skipper, Erlaitz Basabe Obregon, Karl Anker Jorgensen
Summary: This study presents a novel enantioselective (8+3) cycloaddition reaction using a chiral bifunctional Bronsted base catalyst. The reaction leverages an anionic activation strategy and differs from typical Lewis-acid activation protocols. Experimental and computational results support the relevance of this reaction and its potential application in organic synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Ming Bao, Karlos Lopez, Raj Gurung, Hadi Arman, Michael P. Doyle
Summary: A highly enantioselective synthesis of chiral dihydro-3H-carbazole-2-carboxylate derivatives is achieved via a one-pot cascade reaction catalyzed by nickel(II) perchlorate hexahydrate and scandium(III) trifluoromethanesulfonate. The reaction proceeds under mild conditions and provides the desired products in high yields and enantioretention. Furthermore, these dihydro-3H-carbazole-2-carboxylates can be transformed into decarboxylated compounds through hydrolysis and decarboxylation under unexpectedly mild reaction conditions, giving moderate yields with high retention of enantiomeric purity.
Article
Chemistry, Multidisciplinary
Shintaro Takahashi, Manuel A. Ramos-Enriquez, Ekaterina Bellan, Antoine Baceiredo, Nathalie Saffon-Merceron, Norio Nakata, Daisuke Hashizume, Vicenc Branchadell, Tsuyoshi Kato
Summary: A novel stable donor/acceptor-supported Mn-I-metallasilanone 3 was synthesized, exhibiting high reactivity towards small molecules like H-2 or ethylene gas under mild conditions due to its highly strained three-membered cyclic structure induced by intramolecular silanone-Mn-I interaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
D. A. Denisov, R. A. Novikov, Yu. V. Tomilov
Summary: The diastereoselective synthesis of donor-acceptor bicyclopropyl, 8-phenyldispiro[2.3.2.0]-nonane-1,1-dicarboxylate, was successfully achieved, utilizing Lewis acids as synthetic equivalents of cis-1,6-zwitterionic intermediates. Different cyclization reactions were observed depending on the presence of GaCl3 or EtAlCl2, showcasing the versatile reactivity of the compound under different conditions. Additionally, the reaction with 4-phenyl-1,2,4-triazoline-3,5-dione in the presence of Yb(OTf)(3) resulted in the formation of an eight-membered heterocycle through an ionic [6+2] cycloaddition.
RUSSIAN CHEMICAL BULLETIN
(2021)
Article
Chemistry, Organic
Shiksha Deswal, Avishek Guin, Akkattu T. Biju
Summary: The use of benzotriazoles as nucleophilic triggers in the three-component Yb(OTf)(3)-catalyzed ring-opening 1,3-aminofunctionalization of donor-acceptor (D-A) cyclopropanes is described. The reaction yields 1,3-aminohalogenation products in up to 84% yield when N-halo succinimide (NXS) is used as the third component. Alkyl halides or Michael acceptors as the third components lead to the formation of 3,1-carboaminated products in up to 96% yield in a one-pot operation. Using Selectfluor as the electrophile, the reaction affords 1,3-aminofluorinated products in a 61% yield.
Article
Chemistry, Physical
Ming Bao, Karlos Lopez, Raj Gurung, Hadi Arman, Michael P. Doyle
Summary: A highly enantioselective synthesis of chiral dihydro-3H-carbazole-2-carboxylate derivatives is achieved via a one-pot cyclopentannulation-rearrangement cascade reaction. The reaction is catalyzed by nickel(II) perchlorate hexahydrate and scandium(III) trifluoromethanesulfonate, and involves the use of 3-methylindole and non-racemic donor-acceptor cyclopropanes. The resulting products show high yields and enantioretention under mild reaction conditions, and further transformation into decarboxylated compounds can be achieved with moderate yields and high enantiomeric purity.
Review
Chemistry, Physical
Ming Bao, Michael P. Doyle
Summary: The [3+n]-cycloaddition reactions using chiral catalysts and racemic cyclopropanes or achiral catalysts and chiral, non-racemic cyclopropanes have proven to be important transformations for the synthesis of carbocyclic and heterocyclic compounds, showing both mechanistic and structural advantages in ring formation.
Article
Chemistry, Multidisciplinary
Meifeng Hou, Jiajun Li, Fucai Rao, Zuliang Chen, Yingjing Wei
Summary: In this study, the construction of N-heterocyclic eight-membered rings using Lu(OTf)(3) as a catalyst is reported. A formal [4+4] cycloaddition reaction of cyclobutane 1,1-diesters with anthranils was used to deliver oxa-bridged eight-membered heterocycles, providing a potential method for building complex azocine compounds.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Gwyndaf A. Oliver, Maximilian N. Loch, Andre U. Augustin, Pit Steinbach, Mohammed Sharique, Uttam K. Tambar, Peter G. Jones, Christoph Bannwarth, Daniel B. Werz
Summary: The paper presents rare examples of cycloadditions involving D-A cyclopropanes and cyclobutanes with N-sulfinylamines and a sulfur diimide, leading to the formation of five- and six-membered rings containing adjacent heteroatoms. A one-pot, two-step strategy is introduced for the formal insertion of HNSO2 into D-A cyclopropanes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Physical
Tatyana Shabatina, Olga Vernaya, Aleksei Shumilkin, Alexander Semenov, Mikhail Melnikov
Summary: The increasing appearance of antibiotic-resistant strains of microorganisms is a pressing modern problem. Nanoparticles offer a potential solution as new antibacterial agents, as they can target pathogenic microorganisms using mechanisms different from antibiotics. These particles possess a wide spectrum of antibacterial activity and can be conjugated with drugs for targeted delivery systems.
Article
Biochemistry & Molecular Biology
Alexey N. Bilyachenko, Victor N. Khrustalev, Anna Y. Zueva, Ekaterina M. Titova, Grigorii S. Astakhov, Yan Zubavichus, Pavel Dorovatovskii, Alexander A. Korlyukov, Lidia S. Shul'pina, Elena S. Shubina, Yuriy N. Kozlov, Nikolay S. Ikonnikov, Dmitri Gelman, Georgiy B. Shul'pin
Summary: The first examples of metallasilsesquioxane complexes were synthesized and their structures and catalytic activities were studied. The characteristics of alkaline metal ions and variations in nitrogen ligands were found to be influential in the formation of supramolecular structures. Hydroxyl radicals were identified as playing a crucial role in the catalytic oxidation reactions studied.
Article
Biochemistry & Molecular Biology
Vladimir K. Osmanov, Evgeniy Chipinsky, Victor N. Khrustalev, Alexander S. Novikov, Rizvan Kamiloglu Askerov, Alexander O. Chizhov, Galina N. Borisova, Alexander Borisov, Maria M. Grishina, Margarita N. Kurasova, Anatoly A. Kirichuk, Alexander S. Peregudov, Andreii S. Kritchenkov, Alexander G. Tskhovrebov
Summary: A practical method for synthesizing 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinone was reported. Novel organoselenium derivatives were characterized using various techniques and exhibited multiple remarkable chalcogen bonding interactions in the solid state.
Article
Biochemistry & Molecular Biology
Alexey N. Bilyachenko, Ivan S. Arteev, Victor N. Khrustalev, Anna Y. Zueva, Lidia S. Shul'pina, Elena S. Shubina, Nikolay S. Ikonnikov, Georgiy B. Shul'pin
Summary: A family of octacopper cage methylsilsesquioxanes with prismatic structures has been synthesized and characterized. The distortion of the prismatic cages was found to be influenced by additional alkaline metal ions, solvating ligands, and encapsulating species. Opportunities for designing supramolecular 1D structures were identified, such as formate linkers between copper centers and crown ether-like contacts between cesium ions and siloxane cycles. The Cu8Cs2-based complex 4 exhibited high catalytic activity in alkane and alcohol oxidation reactions.
Article
Polymer Science
Ekaterina M. Zubanova, Tatiana A. Ivanova, Evgenii A. Ksendzov, Sergei Kostjuk, Peter S. Timashev, Mikhail Ya Melnikov, Elena N. Golubeva
Summary: This study investigated the coil-to-globule transition and dynamics of inhomogeneities in aqueous solutions of graft copolymers with different contents of oligolactide groups using EPR spectroscopy. It was found that an increase in oligolactide content leads to the formation of looser globules, allowing for the exchange of probe molecules between the globules and the external solution.
Article
Chemistry, Physical
Artem P. Dysin, Anton R. Egorov, Omar Khubiev, Roman Golubev, Anatoly A. Kirichuk, Victor N. Khrustalev, Nikolai N. Lobanov, Vasili V. Rubanik, Alexander G. Tskhovrebov, Andreii S. Kritchenkov
Summary: In this study, new Cu(II)/chitosan-based systems were designed and evaluated for their catalytic properties in various organic transformations. The use of different treatments and coatings resulted in efficient catalysts for different types of reactions. The reactions were conducted in water and the product was easily isolated from the catalyst.
Article
Chemistry, Organic
Vitaly V. Shorokhov, Danila S. Lebedev, Maksim A. Boichenko, Sergey S. Zhokhov, Igor V. Trushkov, Olga A. Ivanova
Summary: A method for the synthesis of isoindoline derivatives was developed by using a domino reaction with a donor-acceptor cyclopropane and various primary amines. Under the hydrogenolysis conditions, the resulting N-benzyl-1,3-dihydroisoindole underwent selective cleavage of the exocyclic N-CH2Ar bond and followed by lactamization to form benzo[b]pyrrolizidinone. The same product can also be obtained by starting with reduction of the azidomethyl group at the ortho position of the donor aromatic substituent. Similarly, the generation of the o-2-aminoethyl group led to the formation of benzo[e]indolizidinone through two successive cyclization reactions.
CHEMISTRY OF HETEROCYCLIC COMPOUNDS
(2023)
Article
Chemistry, Physical
Nina K. Ratmanova, Ivan A. Andreev, Vitaly A. Shcherbinin, Olga A. Ivanova, Irina I. Levina, Victor N. Khrustalev, Igor V. Trushkov
Summary: Triple-role thiocyanate-containing protic ionic liquids (PILs) were used as a regenerable solvent, a Bronsted acid catalyst, and a nucleophile source to achieve the ring-opening of 1,3-indanedione-based donor-acceptor cyclopropanes.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Review
Biochemistry & Molecular Biology
Tatyana I. Shabatina, Olga I. Vernaya, Mikhail Y. Melnikov
Summary: The appearance and increasing number of antibiotic-resistant microorganisms is a global problem. Nanoscale inorganic materials have the potential to combat this issue. This article discusses the mechanisms of microbial resistance to antibiotics, the actions of inorganic nanoparticles on bacterial cells, and the benefits of their combined use with antibacterial drugs. The prospects of using metal and metal oxide nanoparticles in targeted delivery systems for antibacterial compositions are also explored.
Review
Pharmacology & Pharmacy
Tatyana I. Shabatina, Olga I. Vernaya, Nikolay L. Shimanovskiy, Mikhail Ya. Melnikov
Summary: The development of antiviral treatment and anticancer theragnostic agents in recent decades has been closely associated with nanotechnologies, especially inorganic nanoparticles (INPs) made of metal and metal oxides. INPs, with their large specific surface area and high activity, can be easily functionalized for various applications such as targeted drug delivery, magnetic hyperthermia, and plasmonic photothermal therapies. The magnetic properties of iron oxide and ferrite nanoparticles make them ideal for magnetic resonance imaging and targeted cancer therapy. Moreover, gold and silver nanoparticles show promise in plasmonic photothermal and antiviral therapies, respectively.
Article
Chemistry, Organic
Olga A. A. Ivanova, Vitaly V. V. Shorokhov, Ivan A. A. Andreev, Nina K. K. Ratmanova, Victor B. B. Rybakov, Elena D. D. Strel'tsova, Igor V. V. Trushkov
Summary: A donor-acceptor cyclopropane, derived from 1,3-indanedione and bearing an ortho-ethoxymethyl-protected phenolic group at the donor aryl substituent, was synthesized through a reaction sequence involving Knoevenagel condensation and Corey-Chaykovsky cyclopropanation. The structure of the synthesized cyclopropane was confirmed by single-crystal X-ray diffraction analysis.
Article
Chemistry, Organic
Vitaly V. Shorokhov, Sergey S. Zhokhov, Victor B. Rybakov, Maksim A. Boichenko, Ivan A. Andreev, Nina K. Ratmanova, Igor V. Trushkov, Olga A. Ivanova
Summary: A Lewis acid-promoted domino ring-opening cyclization of readily available donor-acceptor cyclopropanes with a preinstalled electrophilic center, embedded in a donor group, to functionalized 1,2-dihydronaphthalenes is reported. The obtained compounds are transformed to pharmacologically attractive bridged tricyclic esters in a diastereospecific manner.
Article
Chemistry, Organic
Anna E. Vartanova, Irina I. Levina, Nina K. Ratmanova, Ivan A. Andreev, Olga A. Ivanova, Igor Trushkov
Summary: This study investigated the Lewis acid-catalysed reactions of donor-acceptor cyclopropanes with 1,3-disubstituted 5-aminopyrazoles. It was found that under the catalysis of gallium(iii) chloride, the nucleophilic attack of the exocyclic amino group led to the chemoselective three-membered ring opening. On the other hand, in the presence of scandium(iii) triflate, N-alkylation, C(4)-alkylation, or a mixture of both reactions occurred. The C(4)-alkylation products were further transformed into tetrahydropyrazolo[3,4-b]azepines, which have potential applications in medicinal chemistry and pharmacology.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
