Article
Chemistry, Multidisciplinary
Hiroki Tashiro, Masahiro Terada, Itaru Nakamura
Summary: Gold-catalyzed reactions were used to synthesize 2H-azirines with sulfenyl and acyl groups at the 3-position, yielding good to excellent results. These reactions involved internal transfer of sulfinyl oxygen atom and carbene insertion into the N-S bond for ring construction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Pei-Pei Xu, Su-Ge Xin, Xue Li, Cui Liang, Dong-Liang Mo
Summary: We developed a copper(II)-catalyzed [3+2] cycloaddition reaction between N-aryl-alpha,beta-unsaturated nitrones and disubstituted allenoates to prepare a variety of [1,3]oxazino[3,2-a]indolines and dihydropyrido[1,2-a]indolines in moderate to excellent yields. Mechanistic studies revealed the kinetic preference for [1,3]oxazino[3,2-a]indoline and the thermodynamic preference for dihydropyrido[1,2-a]indoline. The reaction can be easily scaled up and chiral dihydropyrido[1,2-a]indoline can be obtained using a chiral auxiliary. The method demonstrates broad substrate scope, good functional group tolerance, and high diastereoselectivity, making it highly significant.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Fang Li, Chao Pei, Rene M. Koenigs
Summary: Our studies on the reaction of organoselenium compounds with triazoles reveal two different cascade reactions, shedding light on the multiple roles of organoselenium compounds in rearrangement reactions and mediating a free ylide reaction mechanism. Theoretical and experimental studies were conducted to provide an understanding of the reaction mechanism.
Review
Chemistry, Organic
Sishi Zhong, Lei Xu, Yunfei Cai
Summary: The Piancatelli reaction is a significant organic synthesis reaction, which can construct diversified functionalized cyclopentenones and polycyclic cyclopentanones. In addition, there have been developments in chiral catalytic reactions in this field.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Physical
Dongdong Wang, Mohammad Al-Mamun, Wanbing Gong, Yang Lv, Chun Chen, Yue Lin, Guozhong Wang, Haimin Zhang, Huijun Zhao
Summary: In this study, a new synthetic approach was demonstrated to fabricate N-doped carbon nanotube (N-CNTs) networks as high performance hydrogenation rearrangement (HR) catalyst to efficiently convert biomass-derived furanic aldehydes to cyclopentanones. The mechanism of Co-catalyzed bulk g-C3N4 decomposition/carbonization and formation of CNTs was unveiled, along with the discovery of a new HR pathway.
Article
Chemistry, Organic
Chih-Hao Luo, Pei-Ling Wang, Che-Chien Chang
Summary: Various N-(2-bromo-allyl) benzamides were used as starting materials for studying vinyl radical cyclization reactions, which produced beta-aryl-gamma-lactams without affecting the carbonyl group. The cascade radical reaction led to the synthesis of alpha,beta-unsaturated-beta-aryl-gamma-lactam derivatives, with the effects of substituents on the amino and aryl groups examined.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Liselle Atkin, Hannah J. Ross, Daniel L. Priebbenow
Summary: This study investigates the reactivity of acylsilanes and reveals the participation of light-induced siloxy carbenes in intramolecular reactions. Structural misassignments in previous studies are corrected.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Physical
Robert Francke, R. Daniel Little
Summary: Electrochemical catalysis is a valuable method for conducting redox-neutral reactions at mild conditions. It involves injecting electrons or holes into the reactant to induce chemical transformations. Recent advances have been made in understanding the mechanisms and developing new applications in this field. This contribution summarizes the recent progress in electrochemical catalysis.
CURRENT OPINION IN ELECTROCHEMISTRY
(2023)
Review
Chemistry, Organic
Scott Benz, Andrew S. Murkin
Summary: This review examines the use of alpha-ketol rearrangements in various synthetic applications such as asymmetric synthesis, tandem reactions, and the total synthesis and biosynthesis of natural products over the past two decades.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Feifei He, Rene M. Koenigs
Summary: In this study, the tris(pentafluorophenyl)borane-catalyzed reaction of carbazole heterocycles with aryldiazoacetates was reported. It was demonstrated that selective N-H or C-H functionalization could be achieved with good yields under different substrate conditions. The method showed promising application potential in 41 examples.
Article
Chemistry, Multidisciplinary
H. Surya Prakash Rao, Ahana Saha, Satish Vijjapu
Summary: Through research, it was found that the diol derived from allylated camphorquinone undergoes iodine or bromine mediated deep-seated skeletal rearrangement to provide an interesting tricyclic ring system, with the iodo group in the rearranged product offering convenient leverage for further functionalization.
Article
Chemistry, Organic
Someshwar Nagamalla, Ranjeet A. Dhokale, Frederick J. Seidl, Joel T. Mague, Shyam Sathyamoorthi
Summary: The first examples of rearrangement reactions of allylic silanol substrates into linear ketone and 5-membered cyclic silanediol organomercurial products are presented in this study. The reactions are mediated by Hg(OTf)(2) and show differences in the use of base, solvent, and temperature. Mechanistic studies suggest that these products result from a series of cascading transformations in one pot, with a DFT analysis providing insights into the rearrangement process.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Kosuke Yasui, Miharu Kamitani, Hayato Fujimoto, Mamoru Tobisu
Summary: This study reports on the N-heterocyclic carbene (NHC)-catalyzed Truce-Smiles rearrangement of aniline derivatives, where an unactivated C(aryl)-N bond is cleaved to form a new C(aryl)-C bond. The key to the success of this reaction lies in the utilization of highly nucleophilic NFIC, which enables the formation of a highly nucleophilic ylide intermediate generated from an alpha,beta-unsaturated amide.
Article
Chemistry, Multidisciplinary
Timon Kurzawa, Reinhold Zimmer, Ernst-Ulrich Wuerthwein, Hans-Ulrich Reissig
Summary: In this study, the acetic anhydride-promoted reaction of a model pyrimidine N-oxide to a 4-acetoxymethyl-substituted pyrimidine derivative was investigated. The experiments and quantum chemical calculations revealed that a (pyrimidin-4-yl)methyl radical is a key species in the rearrangement and that the reaction proceeds through radical intermediates. The calculations also showed that both concerted [3,3]-sigmatropic rearrangements and stepwise processes are energetically feasible.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Xiaoying Zou, Lvyin Zheng, Xiaoya Zhuo, Yumei Zhong, Yingying Wu, Beining Yang, Qifang He, Wei Guo
Summary: A copper-promoted aerobic oxidative [3+2] cyclo-addition reaction is developed for the synthesis of substituted pyrazoles from N,N-disubstituted hydrazines and alkynoates in the presence of bases. This work involves direct C(sp(3))-H functionalization and the formation of new C-C/C-N bonds. In this strategy, inexpensive and easily available Cu2O serves as the promoter and air acts as the green oxidant. The reaction exhibits the advantages of high atom and step economy, high regioselectivity, and easy operation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Anastasia A. Fadeeva, Sema L. Ioffe, Andrey A. Tabolin
SYNTHESIS-STUTTGART
(2020)
Article
Chemistry, Organic
Savva A. Ponomarev, Roman Larkovich, Alexander S. Aldoshin, Andrey A. Tabolin, Sema L. Ioffe, Jonathan Gross, Till Opatz, Valentine G. Nenajdenko
Summary: The Diels-Alder reaction of beta-fluoro-beta-nitrostyrenes with cyclic 1,3-dienes was studied, leading to the synthesis of a series of novel monofluorinated norbornenes with yields up to 97%. Activation parameters were calculated using kinetic data from reactions with 1,3-cyclopentadiene and 1,3-cyclohexadiene, demonstrating the synthetic utility of the cycloadducts obtained.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Pavel Yu. Ushakov, Alexey Yu. Sukhorukov, Sema L. Ioffe, Andrey A. Tabolin
Summary: The Suzuki-Miyaura cross-coupling reaction was suggested as the final C-C bond forming step in a convenient diastereoselective route to trisubstituted isoxazolines, with the synthetic utility of the obtained isoxazolines demonstrated through conversion into valuable products.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Yulia A. Antonova, Sema L. Ioffe, Alexey Yu. Sukhorukov, Andrey A. Tabolin
Summary: Sequential acylation-silylation of nitroalkanes leads to high yields of O-silylated alpha-acyloxyoximes. The reaction has a broad substrate scope for both nitroalkanes and acylating agents, with the ability to adjust reaction conditions based on the specific substrate. Additionally, the study demonstrates the application of the obtained oxime derivatives in organic synthesis.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Anastasia A. Fadeeva, Sema L. Ioffe, Andrey A. Tabolin
Summary: A new method for the synthesis of fully substituted 3-haloisoxazoles has been developed, involving the synthesis of isoxazoline N-oxides from alpha-halonitroalkenes followed by dehydration mediated by the silyl triflate/triethylamine system.
TETRAHEDRON LETTERS
(2021)
Article
Biochemistry & Molecular Biology
Alexander S. Aldoshin, Andrey A. Tabolin, Sema L. Ioffe, Valentine G. Nenajdenko
Summary: The study investigates catalyst-free conjugate addition of pyrroles to beta-Fluoro-beta-nitrostyrenes, resulting in the formation of target products under solvent-free conditions. The kinetics of the reaction are studied to reveal the reaction characteristics.
Article
Chemistry, Multidisciplinary
Vladimir A. Motornov, Andrey A. Tabolin, Sema L. Ioffe
Summary: A facile and versatile method for the synthesis of [5,5]-annulated N-fused heterocycles, pyrrolo[2,1-b]thiazoles and pyrrolo[1,2-b]indazoles, via oxidative [3+2] annulation of nitroalkenes and azolium ylides in the presence of copper(ii) has been developed. The reaction is performed under mild conditions using copper(ii) trifluoroacetate/2,6-lutidine system and gives moderate to good yields of the target N-fused heterocycles. Unique fluorinated derivatives can also be accessed using this methodology with alpha-fluoronitroalkenes.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Organic
Yana Lichtenstein, Ivan S. Golovanov, Sema L. Ioffe, Andrey A. Tabolin
Summary: The synthesis of substituted N-silyloxy aziridines through the reaction of silyl nitronates and enol diazo acetates is described. The process involves the in situ transformation of enol diazo acetates into donor acceptor cyclopropenes, their [3+2]-cycloaddition with nitronates, and subsequent rearrangement of fused isoxazolidine intermediates.
Article
Chemistry, Multidisciplinary
Vladimir A. Motornov, Andrey A. Tabolin, Valentine G. Nenajdenko, Sema L. Ioffe
Summary: The oxidative [3+2]-annulation reactions between nitroalkenes and pyridazinium ylides mediated by Cu(OAc)(2).H2O were explored, leading to functionalized pyrrolo[1,2-b]pyridazines and pyrrolo[1,2-a]phthalazines. Mechanistic features of the reaction were studied to support the stepwise [3+2]-cycloaddition/oxidation/HNO2 elimination mechanism, with partially saturated primary [3+2]-adducts identified as key intermediates.
Article
Chemistry, Organic
Alexander A. Lukoyanov, Andrey A. Tabolin, Yulia Nelyubina, Sema L. Ioffe, Alexey Yu. Sukhorukov
Summary: It has been discovered that six-membered cyclic nitronates can react with aryne to form a tricyclic nitroso acetal. This reaction involves the selective cleavage of the N-O bond of the isoxazoline ring, leading to the synthesis of compounds with potential synthetic value.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Anastasia A. Fadeeva, Sema L. Ioffe, Andrey A. Tabolin
Summary: A convenient method for the preparation of 4,5-disubstituted 3-halo- (chloro-, bromo-) isoxazolines has been developed. Acetyl bromide serves as a reducing agent, successfully converting 3-halosubstituted isoxazoline N-oxides into desired deoxygenated derivatives with high yields. This approach is regioselective and eliminates the need for hazardous phosgene oximes. The obtained products have demonstrated selective transformations.
Article
Biochemistry & Molecular Biology
Yulia A. Antonova, Yulia V. Nelyubina, Sema L. Ioffe, Andrey A. Tabolin
Summary: A Rh(II)-catalyzed reaction of cyclic nitronates with vinyl diazoacetates proceeds as an annulation reaction, producing bicyclic unsaturated nitroso acetals. Optimization of reaction conditions revealed the use of Rh(II) octanoate as the preferred catalyst in THF at room temperature, allowing the preparation of target products in good yields and excellent diastereoselectivity. Under basic conditions, these nitroso acetals undergo ring contraction into the corresponding pyrroles, and both transformations can be performed in a one-pot fashion.
Article
Chemistry, Organic
Alexander A. A. Lukoyanov, Andrey A. A. Tabolin, Yulia V. V. Nelyubina, Svetlana A. A. Aksenova, Alexey Yu. Sukhorukov
Summary: The reaction between cyclic nitronates and Kobayashi's aryne precursors leads to the formation of tricyclic benzene-fused nitroso acetals through [3 + 2]-cycloaddition. This process is regio- and stereoselective, yielding cycloadducts with up to four contiguous stereogenic centers. These nitroso acetals can be used as convenient precursors for the synthesis of valuable polysubstituted aminodiols through catalytic hydrogenolysis of the N-O bonds. Furthermore, protic acids cause the unusual fragmentation of the cyclic nitroso acetal moiety, leading to the synthesis of a previously unknown hexahydrobenzo[4,5]isoxazolo[2,3-a]azepine scaffold through heterolytic N-O bond cleavage and Beckmann-type reaction.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Pavel Yu. Ushakov, Ivan S. Golovanov, Sema L. Ioffe, Andrey A. Tabolin
Summary: New annulation reactions involving aliphatic nitro compounds and vinyl sulfonium salts were achieved by controlling the reaction direction through changing the solvent and the base. This method is efficient, tolerant to various functional groups, and easy to implement. The synthetic value of the resulting products was demonstrated through selective reduction, selective C-C bond cleavage, and other transformations.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Vladimir A. Motornov, Andrey A. Tabolin, Yulia V. Nelyubina, Valentine G. Nenajdenko, Sema L. Ioffe
Summary: A new efficient method for the synthesis of multifunctionalized pyrrolidines via copper-catalyzed diastereoselective [3 + 2]-cycloaddition was developed, leading to the formation of novel fluorinated heterocycles like beta-fluoro-beta-nitropyrrolidines. The products exhibited good to excellent yields and high diastereoselectivity, and subsequent transformations resulted in the synthesis of medicinally attractive beta-fluoro-NH-pyrroles and other derivatives.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
