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Journal articles on the topic '1,3-dipolar cycloaddition reaction'

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Published: 18 May 2024

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1

WANG, JING-FANG, DONG-QING WEI, CHUN-FANG WANG, YONG YE, YI-XUE LI, YONG LUO, WEN-WU WANG, LUN-ZU LIU, and YU-FEN ZHAO. "A THEORETICAL STUDY ON THE MECHANISM OF 2:1 1, 3 DIPOLAR CYCLOADDITION REACTIONS." Journal of Theoretical and Computational Chemistry 06, no. 04 (December 2007): 861–67. http://dx.doi.org/10.1142/s0219633607003489.

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The reactions between nitrile oxides and alkenes are of considerable interest in organic synthesis as the resulting heterocycles are versatile intermediates for the synthesis of natural products and biologically active compounds. In this paper, we design a series of reactions of phosphonyl nitrile oxides with acrylonnitrile, which can give 2:1 cycloaddition products with no crystal structure released so far, and present a detailed theoretical study on the mechanism of the 2:1 1, 3-dipolar cycloaddition reaction, which has been explored with density functional theory calculations at B3LYP/6-31G* level. The results reveal that the following mechanism is quite possible. Firstly, it starts as a normal 1,3-dipolar cycloaddition reaction to produce a regiospecific 1:1 product. Subsequently, highly reactive diisopropanyl phosphonyl nitrile oxide sequentially reacts with the aforementioned regiospecific 1:1 product and gives the corresponding cycloadduct. Further study is underway to expand the scope of this methodology, as well as to ascertain mechanistic details of the cycloaddition process.

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2

Grygorenko, Oleksandr O., Viktoriia S. Moskvina, Oleksandr V. Hryshchuk, and Andriy V. Tymtsunik. "Cycloadditions of Alkenylboronic Derivatives." Synthesis 52, no. 19 (June 24, 2020): 2761–80. http://dx.doi.org/10.1055/s-0040-1707159.

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The literature on cycloaddition reactions of boron-containing alkenes is surveyed with 132 references. The data are categorized according to the reaction type ([2+1], [2+2], [3+2], [4+2], and [4+3] cycloadditions). The cyclopropanation and the Diels–Alder reactions of alkenylboronic derivatives have been studied more or less comprehensively, and for some substrates, they can be considered as convenient methods for the rapid regio- and stereoselective construction of even complex cyclic systems. Other types of the cycloadditions, as well as mechanistic aspects of the processes, have been addressed less thoroughly in the previous works.1 Introduction2 [2+1] Cycloaddition2.1 Cyclopropanation2.1.1 With Methylene Synthetic Equivalents2.1.2 With Substituted Carbenoids2.2 Epoxidation2.3 Aziridination3 [2+2] Cycloaddition4 [3+2] Cycloaddition4.1 With Nitrile Oxides4.2 With Diazoalkanes4.3 With Nitrones4.4 With Azomethine Ylides5 [4+2] Cycloaddition6 [4+3] Cycloaddition7 Conclusions and Outlook

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3

Salem, Mohammed A., Moustafa A. Gouda, and Ghada G. El-Bana. "Chemistry of 2-(Piperazin-1-yl) Quinoline-3-Carbaldehydes." Mini-Reviews in Organic Chemistry 19, no. 4 (June 2022): 480–95. http://dx.doi.org/10.2174/1570193x18666211001124510.

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Abstract: This review described the preparation of 2- chloroquinoline-3-carbaldehyde derivatives 18 through Vilsmeier-Haack formylation of N-arylacetamides and the use of them as a key intermediate for the preparation of 2-(piperazin-1-yl) quinoline-3-carbaldehydes. The synthesis of the 2- (piperazin-1-yl) quinolines derivatives was explained through the following chemical reactions: acylation, sulfonylation, Claisen-Schmidt condensation, 1, 3-dipolar cycloaddition, one-pot multicomponent reactions (MCRs), reductive amination, Grignard reaction and Kabachnik-Field’s reaction.

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4

Caraculacu, Adrian A., Elena Scorţanu, and Georgeta Caraculacu. "New Parabanate Products by 1, 3-Dipolar Cycloaddition Reaction (‘Criss-Cross’ Cycloaddition)." High Performance Polymers 11, no. 4 (December 1999): 477–82. http://dx.doi.org/10.1088/0954-0083/11/4/311.

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5

Ogurtsov, Vladimir A., and Oleg A. Rakitin. "New Cycloadditon Reaction of 2-Chloroprop-2-enethioamides with Dialkyl Acetylenedicarboxylates: Synthesis of Dialkyl 2-[4,5-Bis(alkoxycarbonyl)-2-(aryl{alkyl}imino)-3(2H)-thienylidene]-1,3-dithiole-4,5-dicarboxylates." Molecules 27, no. 20 (October 14, 2022): 6887. http://dx.doi.org/10.3390/molecules27206887.

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The 1,3-dipolar cycloaddition of 1,2-dithiole-3-thiones with alkynes to form 1,3-dithioles is one of the most studied reactions in this class of polysulfur-containing heterocycles. Nucleophilic substitution of chlorine atoms in dimethyl 2-(1,2-dichloro-2-thioxoethylidene)-1,3-dithiole-4,5-dicarboxylate, which was obtained by addition one molecules of DMAD to 4,5-dichloro-3H-1,2-dithiole-3-thione, led to a series of 2-chloro-2-(1,3-dithiol-2-ylidene)ethanethioamides. Cycloaddition reaction of 2-chloro-2-(1,3-dithiol-2-ylidene)ethanethioamides with activated alkynes led to the unexpected formation of 2-(thiophen-3(2H)-ylidene)-1,3-dithioles via new intermediate, 1-(1,3-dithiol-2-ylidene)-N-phenylethan-1-yliumimidothioate. Structure of dimethyl2-(4,5-bis(methoxycarbonyl)-2-(phenylimino)thiophen-3(2H)-ylidene)-1,3-dithiole-4,5-dicarboxylate was finally proven by single crystal X-ray diffraction study. Optimized reaction conditions and a mechanistic rationale for the 1,3-dipolar cycloaddition of novel intermediate are presented.

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6

Winne, Johan, Jan Hullaert, Bram Denoo, Mien Christiaens, and Brenda Callebaut. "Heterocycles as Moderators of Allyl Cation Cycloaddition Reactivity." Synlett 28, no. 18 (July 27, 2017): 2345–52. http://dx.doi.org/10.1055/s-0036-1588511.

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For the rapid elaboration of polycarbocyclic scaffolds, prevalent in many important families of terpenoid natural products, allyl cations derived from simple heterocyclic alcohols can be used as versatile reaction partners in both (4+3) and (3+2) cycloaddition pathways. Our recent progress in this area is outlined, pointing towards the untapped potential of heterocycles to act as reagents in novel or known but challenging organic transformations.1 Heterocyclic Reagents2 Cycloadditions and Allyl Cations3 Furfuryl Cations in Cycloadditions4 Heterocycle-Substituted Cations in Cycloadditions5 Mechanistic Considerations6 Conclusions and Outlook

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7

Mohtat, Bita, Seyyed Amir Siadati, and Mohammad A. Khalilzadeh. "Understanding the mechanism of the 1,3-dipolar cycloaddition reaction between a thioformaldehyde S-oxide and cyclobutadiene: Competition between the stepwise and concerted routes." Progress in Reaction Kinetics and Mechanism 44, no. 3 (May 12, 2019): 213–21. http://dx.doi.org/10.1177/1468678319845863.

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Changing the mechanism of the widely used 1,3-dipolar cycloaddition reaction from its usual asynchronous one-step pattern to the rarely observed stepwise form leads to the emergence of intermediates, side products, and other impurities. Thus, it is crucial to determine the nature of the mechanism of the 1,3-dipolar cycloaddition reaction between a special 1,3-dipole and a specified dipolarophile (by theoretical methods) before using them for synthesizing a desired product. In this study, therefore, we have investigated the possibility of some probable intermediates emergence in the 1,3-dipolar cycloaddition reaction between cyclobutadiene and thioformaldehyde S-oxide. The results showed that emergence of Int (B) (−52.1 kcal mol−1) via transition state (B-1) is favorable both thermodynamically and kinetically (in comparison with all other stepwise routes). That is, developing probable impurities should not be neglected at least in the cases of the reactions between some thioformaldehyde S-oxide and some dipolarophiles.

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8

El-Sayed, Wael A., and Adel A. H. Abdel-Rahman. "Copper-catalyzed Synthesis and Antimicrobial Activity of Disubstituted 1,2,3-Triazoles Starting from 1-Propargyluracils and Ethyl (4-Azido- 1,2,3-trihydroxybutyl)furan-3-carboxylate." Zeitschrift für Naturforschung B 65, no. 1 (January 1, 2010): 57–66. http://dx.doi.org/10.1515/znb-2010-0110.

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1,3-Dipolar cycloaddition reactions of 1-propargyluracils 2a - h with the azido derivative 3 afforded the corresponding 1,2,3-triazoles 4a - h. Hydrazinolysis of the esters 4a - h gave the corresponding acid hydrazides 5a - h. Reaction of 5a - h with carbon disulfide in ethanol afforded 6a - h. The antimicrobial activity of compounds 4 - 6 was determined

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9

Hunnur, Raveendra K., Prashant R. Latthe, and Bharati V. Badami. "1,3-Dipolar Cycloaddition Reactions in Heterocyclic Synthesis. Synthesis of [1-[4-(thiazolyl/imidazothiazolyl/triazolyl)phenyl]-1H-pyrazole-3,4-dicarboxylate esters from 3-(4-acetylphenyl)sydnone." Journal of Chemical Research 2005, no. 9 (September 2005): 592–94. http://dx.doi.org/10.3184/030823405774308907.

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Cycloaddition of 3-(4-acetylphenyl)sydnone (1) with DMAD gave dimethyl 1-(4-acetylphenyl)-1H-pyrazole-3,4-dicarboxylate (2), which on bromination yielded the corresponding monobromoacetyl (3) and dibromoacetyl (4) derivatives. Both compounds 3 and 4 on reaction with thiourea and thioacetamide afforded the 2-amino- (5) and the 2-methyl- (6) thiazole derivatives respectively, while compound 3 on reaction with 2-aminothiazole gave the imidazothiazole 7. Compound 3 was converted into its azide (8), which on 1,3-dipolar cycloaddition with DMAD afforded the 1,2,3-triazole-4,5-dicarboxylate (9).

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10

Mawhinney, Robert C., Heidi M. Muchall, and Gilles H. Peslherbe. "A computational study of the 1,3-dipolar cycloaddition reaction mechanism for nitrilimines." Canadian Journal of Chemistry 83, no. 9 (September 1, 2005): 1615–25. http://dx.doi.org/10.1139/v05-179.

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The [3+2] and [1+2] cycloaddition pathways between ethene and a series of 13 nitrilimines (R1CNNR2) have been examined by density functional theory [PBE0/6-311++G(2df,pd)] calculations. All reactions have low barriers ranging from 14.14 (R1 = CH3, R2 = H) to 1.01 (R1 = R2 = F) kcal mol1, and large reaction exothermicities consistent with the transient nature of nitrilimines. The [3+2] and [1+2] transition-state structures are very similar, mainly differing in the relative orientation of their fragments and the newly forming CC bond distance, and exhibit only minor deviations from the structures of the reactants. Both reaction pathways are concerted and asynchronous, but the [1+2] reaction has a greater degree of asynchronicity. Examination of the frontier molecular orbitals reveals that both the [3+2] and [1+2] barrier heights are related to two sets of orbital interactions, with the interaction between the lowest unoccupied molecular orbital π [Formula: see text] of nitrilimine and the highest occupied molecular orbital of ethene in common. The second interaction in both cases is carbene-like. A relationship between the weights of the 1,3-dipolar resonance contribution in the various nitrilimines and the corresponding [3+2] barrier heights was not found, but a good correlation could be found between the [1+2] barrier heights and both the 1,3-dipolar and carbene contributions. Inspection of the potential energy surface in the vicinity of the two transition states for the reaction between unsubstituted nitrilimine and ethene suggests that the observed [3+2] product is a result of an initial carbene-like approach of the two fragments followed by a ridge bifurcation that leads to the [3+2] product minimum. Key words: nitrilimines, 1,3-dipole, carbene, [3+2] cycloaddition, [1+2] cycloaddition, density functional theory (DFT).

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11

Deng, Yongming, Qing-Qing Cheng, and Michael Doyle. "Asymmetric [3+3] Cycloaddition for Heterocycle Synthesis." Synlett 28, no. 14 (July 5, 2017): 1695–706. http://dx.doi.org/10.1055/s-0036-1588453.

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Asymmetric syntheses of six-membered ring heterocycles are important research targets not only in synthetic organic chemistry but also in pharmaceuticals. The [3+3]-cycloaddition methodology is a complementary strategy to [4+2] cycloaddition for the synthesis of heterocyclic compounds. Recent progress in [3+3]-cycloaddition processes provide powerful asymmetric methodologies for the construction of six-membered ring heterocycles with one to three heteroatoms in the ring. In this account, synthetic efforts during the past five years toward the synthesis of enantioenriched six-membered ring heterocycles through asymmetric [3+3] cycloaddition are reported. Asymmetric organocatalysis uses chiral amines, thioureas, phosphoric acids, or NHC catalysis to achieve high enantiocontrol. Transition-metal catalysts used as chiral Lewis acids to activate a dipolar species is an alternative approach. The most recent advance, chiral transition-metal-catalyzed reactions of enoldiazo compounds, has contributed toward the versatile and highly selective synthesis of six-membered heterocyclic compounds.1 Introduction2 Asymmetric Formal [3+3]-Cycloaddition Reactions by Organocatalysis2.1 By Amino-Catalysis2.2 By N-Heterocyclic Carbenes2.3 By Bifunctional Tertiary Amine-thioureas2.4 By Chiral Phosphoric Acids3 Asymmetric Formal [3+3]-Cycloaddition Reactions by Transition-Metal Catalysis3.1 Copper Catalysis3.2 Other Transition-Metal Catalysis4 Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazo Compounds4.1 Asymmetric [3+3]-Cycloaddition Reactions of Nitrones with Electrophilic Metallo-enolcarbene Intermediates4.2 Dearomatization in Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazoacetates4.3 Asymmetric Stepwise [3+3]-Cycloaddition Reaction of Enoldiazoacetates with Hydrazones5 Summary and Outlook

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12

Santos, Hugo, Amy Distiller, Asha M. D'Souza, Quentin Arnoux, Jonathan M. White, Adam G. Meyer, and John H. Ryan. "1,3-Dipolar cycloaddition reactions of phthalic anhydrides with an azomethine ylide." Organic Chemistry Frontiers 2, no. 6 (2015): 705–12. http://dx.doi.org/10.1039/c5qo00062a.

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A series of phthalic anhydrides underwent a 1,3-dipolar cycloaddition reaction with N-benzylazomethine ylide to produce unstable spiro(isobenzofuran-1,5′-oxazolidin)-3-ones, which underwent a subsequent reductive ring-opening reaction to afford 1(3H)-isobenzofuranones.

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13

Boudriga, Sarra, Saoussen Haddad, Moheddine Askri, Armand Soldera, Michael Knorr, Carsten Strohmann, and Christopher Golz. "Highly diastereoselective construction of novel dispiropyrrolo[2,1-a]isoquinoline derivativesviamulticomponent 1,3-dipolar cycloaddition of cyclic diketones-based tetrahydroisoquinoliniumN-ylides." RSC Advances 9, no. 20 (2019): 11082–91. http://dx.doi.org/10.1039/c8ra09884k.

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A new series of dispiropyrrolo[2,1-a]isoquinoline derivatives was synthesized by multicomponent 1,3-dipolar cycloaddition reaction of tetrahydroisoquinoliniumN-ylides and (E)-3-arylidene-1-phenyl-pyrrolidine-2,5-diones.

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14

Wanapun, D., K. A. Van Gorp, N. J. Mosey, M. A. Kerr, and T. K. Woo. "The mechanism of 1,3-dipolar cycloaddition reactions of cyclopropanes and nitrones A theoretical study." Canadian Journal of Chemistry 83, no. 10 (October 1, 2005): 1752–67. http://dx.doi.org/10.1139/v05-182.

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The 1,3-dipolar cycloaddition reaction of cyclopropanes and nitrones to give tetrahydro-1,2-oxazine has been studied with density functional theory calculations at the B3LYP/6-31+G(d,p) level of theory. Realistic substituents were modelled including those at the 2-, 3-, 4-, and 6-positions of the final oxazine ring product. The strained σ bond of the cyclopropane was found to play the role of an alkene in a conventional [3+2] dipolar cycloaddition. Two distinct, but similar, reaction mechanisms were found an asymmetric concerted pathway and a stepwise zwitterionic pathway. The reaction barriers of the two pathways were nearly identical, differing by less than ~1 kcal/mol, no matter what the substituents were. The effect of a Lewis acid catalyst was examined and found to have a very large effect on the calculated barriers through coordination to the carbonyl oxygen atoms of the diester substituents on the cyclopropane. The reaction barrier was found to decrease by as much as ~19 kcal/mol when using a BF3 molecule as a model for the Lewis acid catalyst. Solvent effects and the nature of the regiospecificity of the reaction were also examined. Trends in the calculated barriers for the reaction were in good agreement with available trends in the reaction rates measured experimentally. Key words: 1,3-dipolar cycloaddition, cyclopropane, nitrone, tetrahydro-1,2-oxazines, ab initio quantum chemistry, mechanism.

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15

Belguedj, Roumaissa, Sofiane Bouacida, Hocine Merazig, Ali Belfaitah, and Abdelmalek Bouraiou. "1-(2′-Benzimidazolylmethyl)-pyridinium ylide in the one-pot synthesis of indolizine and benzimidazo[1,2-a]pyridine derivatives." Zeitschrift für Naturforschung B 70, no. 8 (August 1, 2015): 555–61. http://dx.doi.org/10.1515/znb-2015-0016.

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AbstractFour indolizine derivatives were obtained via 1,3-dipolar cycloaddition reaction of 1-(2′-benzimidazolylmethyl)pyridinium ylide with various electron-deficient alkynes. The reaction of this pyridinium N-ylide with dimethyl maleate gave an unexpected methyl 1-oxo-benzimidazo[1,2-a]pyridine-3-carboxylate. The structures of all reported compounds have been examined by X-ray crystallography and NMR spectroscopy.

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16

Newton, Rebecca, and G. Paul Savage. "Regioselective 1,3-Dipolar Cycloaddition Reactions of 4-Methylene-2-oxazolidinones with Benzonitrile Oxide." Australian Journal of Chemistry 61, no. 6 (2008): 432. http://dx.doi.org/10.1071/ch08111.

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Substituted 4-methylene-2-oxazolidinones were prepared in two steps by cyclizing O-propargyl carbamates, which in turn were prepared from propargyl alcohols and phenyl isocyanate. The 4-methylene-2-oxazolidinones underwent a 1,3-dipolar cycloaddition reaction with benzonitrile oxide to give the corresponding spiro heterocycles. Where the substitution pattern on the oxazolidinone engendered facial asymmetry, the cycloadditon reaction proceeded with 5:1 selectivity for the less hindered face of the dipolarophile.

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17

Petrov, A. O., Georgiy V. Malkov, Sergei V. Karpov, A. V. Shastin, and A. V. Bakeshko. "Kinetic Study of the Polyaddition of Azide-Alkyne AB₂ Monomers in Nonisotermic Conditions." Key Engineering Materials 816 (August 2019): 151–56. http://dx.doi.org/10.4028/www.scientific.net/kem.816.151.

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Nowadays, hyperbranched polymers (HBP) are obtained by different polycondensation and polyaddition reactions [1]. Almost interest is the reaction of 1,3-dipolar cycloaddition of azides to alkynes (1,3-DCA) [2, 3]. There is a series of papers dedicated to the preparation of triazine-triazole HBPs [4, 5, 6]. These polymers were obtained by the reaction of azido-acetylene AB2 monomers polyaddition: 2-azido-4,6-bis (propyne-2-yloxy) -1,3,5-triazine (ABPOT) and 2,4-diazido-6- (propine-2-yloxy) -1,3,5-triazine (DAPOT) (Fig. 1).

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18

Julino, Markus, Philip R. Lowe, and Malcolm F. G. Stevens. "Structural Studies on Bioactive Compounds. Part 31. Interaction of 9-azidoacridine and 1-morpholinocyclohexene: Formation, Decomposition and Rearrangement of the Intermediate 1,2,3-triazoline." Journal of Chemical Research 2000, no. 2 (February 2000): 74–75. http://dx.doi.org/10.3184/030823400103166418.

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9-Azidoacridine 1 and the cyclic enamine 2 undergo a selective 1,3-dipolar cycloaddition reaction to give the 1,2,3-triazoline 3 with the expected regiochemistry. Exposure of the triazoline 3 to methanol induces the extrusion of nitrogen accompanied by a ring contraction to furnish the amidino-acridine 5 in high yield.

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19

Zhu, Shaohua, Yan Zhang, Peipei Li, Wenzhu Bi, Xiaolan Chen, and Yufen Zhao. "Synthesis of novel phosphorylated chrysin derivatives by 1, 3-dipolar cycloaddition reaction." Phosphorus, Sulfur, and Silicon and the Related Elements 192, no. 1 (October 18, 2016): 1–8. http://dx.doi.org/10.1080/10426507.2016.1223076.

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20

Khoroshunova, Yulia V., Denis A. Morozov, Andrey I. Taratayko, Polina D. Gladkikh, Yuri I. Glazachev, and Igor A. Kirilyuk. "Synthesis of 1-azaspiro[4.4]nonan-1-oxyls via intramolecular 1,3-dipolar cycloaddition." Beilstein Journal of Organic Chemistry 15 (August 27, 2019): 2036–42. http://dx.doi.org/10.3762/bjoc.15.200.

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Sterically shielded nitroxides of the pyrrolidine series have shown the highest resistance to reduction. Here we report the synthesis of new pyrrolidine nitroxides from 5,5-dialkyl-1-pyrroline N-oxides via the introduction of a pent-4-enyl group to the nitrone carbon followed by an intramolecular 1,3-dipolar cycloaddition reaction and isoxazolidine ring opening. The kinetics of reduction of the new nitroxides with ascorbate were studied and compared to those of previously published (1S,2R,3′S,4′S,5′S,2″R)-dispiro[(2-hydroxymethyl)cyclopentan-1,2′-(3′,4′-di-tert-butoxy)pyrrolidine-5′,1″-(2″-hydroxymethyl)cyclopentane]-1′-oxyl (1).

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21

Lukevics, E., P. Arsenyan, I. Shestakova, O. Zharkova, I. Kanepe, R. Mezapuke, and O. Pudova. "Cytotoxic Activity of Silyl- and Germyl-Substituted 4,4-Dioxo-3a,6a-Dihydrothieno[2,3−d]isoxazolines-2." Metal-Based Drugs 7, no. 2 (January 1, 2000): 63–66. http://dx.doi.org/10.1155/mbd.2000.63.

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The [2+3] dipolar cycloaddition of nitrile oxides to the double C = C bonds of thiophene-1, 1-dioxides leads to formation of the fused isoxazolines-2 (1, 2). Tumor growth inhibition of these compounds strongly depends on the nature of group IV A element increasing from slightly active tert-butyl derivatives to silicon and germanium containing analogues. The products of benzonitrile oxide cycloaddition have greater cytotoxic effect than the compounds obtained from the cycloaddition reaction of 2, 5-disubstituted thiophene-1, 1-dioxides with acetonitrile oxide. Fused silyl substituted isoxazolines-2 are stronger NO-inducers than their germyl and tert-butyl analogues.

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22

Svete, Jurij, Uroš Grošelj, Franc Požgan, and Bogdan Štefane. "Copper-Catalyzed Azomethine Imine–Alkyne Cycloadditions (CuAIAC)." Synthesis 50, no. 23 (October 5, 2018): 4501–24. http://dx.doi.org/10.1055/s-0037-1610284.

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Although the first example of copper-catalyzed azomethine imine–alkyne cycloaddition (CuAIAC) was published only a year after the seminal papers of Meldal and Sharpless on Cu-catalyzed azide–alkyne cycloaddition (CuAAC), the CuAIAC reaction has remained overlooked by the synthetic community for almost a decade. Since 2010, however, CuAIAC reaction started to emerge as a promising supplement to the well-known CuAAC reaction. The present review surveys primarily the literature on CuAIAC reaction since 2003. Beside this, azomethine imine–alkyne cycloadditions catalyzed by other metals, selected examples of metal-free reactions, and related [3+3] and [3+4] cycloadditions of azomethine imines are presented. All these experimental data indicate the viability of CuAIAC in organic synthesis and the applicability in ‘click’ chemistry.1 Introduction2 Reactions with Acyclic Azomethine Imines3 Reactions with C,N-Cyclic Azomethine Imines4 Reactions with N,N-Cyclic Azomethine Imines5 Reactions with C,N,N-Cyclic Azomethine Imines6 The Mechanism of the CuAIAC Reaction7 Conclusions and Outlook

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23

Zhang, Xiaofeng, Kenny Pham, Shuai Liu, Marc Legris, Alex Muthengi, Jerry P. Jasinski, and Wei Zhang. "Stereoselective synthesis of fused tetrahydroquinazolines through one-pot double [3 + 2] dipolar cycloadditions followed by [5 + 1] annulation." Beilstein Journal of Organic Chemistry 12 (October 18, 2016): 2204–10. http://dx.doi.org/10.3762/bjoc.12.211.

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The one-pot [3 + 2] cycloaddition of an azomethine ylide with a maleimide followed by another [3 + 2] cycloaddition of an azide with the second maleimide gives a 1,5-diamino intermediate which is used for a sequential aminomethylation reaction with formaldehyde through [5 + 1] annulation to afford a novel polycyclic scaffold bearing tetrahydroquinazoline, pyrrolidine, pyrrolidinedione, and N-substituted maleimide in stereoselective fashion.

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24

Kalluraya, Balakrishna, Kaushik B R, and H. M. Somashekarappa. "Effect of Gamma- Irradiation on Structure, Morphology and Thermal Properties of Novel Polyamide Based Thermoset Obtained by Double Cycloaddition." Journal of Modern Materials 7, no. 1 (July 5, 2020): 17–25. http://dx.doi.org/10.21467/jmm.7.1.17-25.

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Cycloaddition reactions gained prominence in macromolecular chemistry for generating macromolecules because of high yields of these reactions, which is a key tool that drives polyaddition reactions. Cycloaddition reaction plays major role in extension of polymerisation or in other words high conversions of monomers to macromolecules of high molecular weights. Until the late 1990s, the major studies regarding cycloadditions in novel polymer synthesis were related to polyaddition reactions. Since then in the field of polymer synthesis the affirmative strengths of these cycloaddition reactions have been exhibited in multi fold polymer design and headway material architecture. Future demand exists in unlatching the capacity of these novel synthetic routes for advanced applications in catalysis, separation, optoelectronics, and analytical media. Thus, we have developed an able and productive synthetic podium for the preparation of a new class of polyimide based on the double 1, 3-dipolar cycloaddition of thiasydnone with bis-maleimide. This paper reports the effect of gamma irradiation on the changes in physico-chemical properties of the polyamide based thermoset synthesised by double cycloaddition approach. The thermoset synthesized by this exclusive approach were irradiated with gamma doses in the range 10- 300 kGy. The substantial effect of gamma radiation and the structural modifications induced on the thermoset have been studied as a function of dose using different characterization techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry- thermo gravimetric analysis (DSC-TGA), Field Emission Scanning Electron Microscope (FESEM) and UV-Vis Spectroscopy.

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Ganushevich, Yulia, Almaz Zagidullin, Svetlana Kondrashova, Shamil Latypov, Vasili Miluykov, Peter Lönnecke, and Evamarie Hey-Hawkins. "Asymmetric 1,3-dipolar cycloaddition reaction of chiral 1-alkyl-1,2-diphospholes with diphenyldiazomethane." RSC Advances 10, no. 64 (2020): 39060–66. http://dx.doi.org/10.1039/d0ra08080b.

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26

Boitsov, Vitali M., Alexander V. Stepakov, Siqi Wang, Alexander S. Filatov, Stanislav V. Lozovskiy, Stanislav V. Shmakov, Olesya V. Khoroshilova, Anna G. Larina, and Stanislav I. Selivanov. "Construction of Spiro[3-azabicyclo[3.1.0]hexanes] via 1,3-Dipolar Cycloaddition of 1,2-Diphenylcyclopropenes to Ninhydrin-Derived Azomethine Ylides." Synthesis 53, no. 12 (January 18, 2021): 2114–32. http://dx.doi.org/10.1055/a-1360-9716.

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AbstractThe multi-component 1,3-dipolar cycloaddition of ninhydrin, α-amino acids (or peptides), and cyclopropenes for the synthesis of spirocyclic heterocycles containing both 3-azabicyclo[3.1.0]hexane and 2H-indene-1,3-dione motifs has been developed. This method provides easy access to 3-azabicyclo[3.1.0]hexane-2,2′-indenes with complete stereoselectivity and a high degree of atom economy under mild reaction conditions. A broad range of cyclopropenes and α-amino acids have been found to be compatible with the present protocol, which offers an opportunity to create a new library of biologically significant scaffold (3-azabicyclo[3.1.0]hexane). In addition, the сomprehensive study of mechanism of azomethine ylide formation from ninhydrin and sarcosine was performed by means of M11 density functional theory (DFT) calculations. It has been revealed that experimentally observed 1-methylspiro[aziridine-2,2′-indene]-1′,3′-dione is a kinetically controlled product of this reaction and appears to act as a 1,3-dipole precursor. This theoretical study also shed light on the main transformations of the azomethine ylide derived from ninhydrin and sarcosine such as a 1,3-dipolar cycloaddition to cyclopropene dipolarophiles, a dimerization reaction and a (1+5) electrocyclization reaction. The antitumor activity of some synthesized compounds against cervical carcinoma (HeLa) cell line was evaluated in vitro by MTS-assay.

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27

Mishriky, Nawal, Adel S. Girgis, and Yehia A. Ibrahim. "Regioselective Synthesis of Spiro[Naphthalene-2(1H),3′-[3H]Pyrazol]-1-Ones Utilizing 1,3-Dipolar Cycloaddition of Nitrilimines." Journal of Chemical Research 2000, no. 1 (January 2000): 2–3. http://dx.doi.org/10.3184/030823400103165527.

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1,3-Dipolar cycloaddition reaction of nitrilimines to a variety of 2-arylmethylidene-3,4-dihydro-1-naphthalenones 1a–h afforded the corresponding spiro[naphthalene-2(1 H),3′-[3 H]pyrazol]-1-ones 3 and not the isomeric spiro[naphthalene-2(1 H),4′-[4 H]pyrazol]-1-ones 4, in high regioselectivity. The structure of the isolated products was established through different spectroscopic techniques and confirmed via HMBC.

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28

Dumitrescu, Denisa, Sergiu Shova, Constantin Draghici, Marcel Mirel Popa, and Florea Dumitrascu. "Synthesis of 1-(2-Fluorophenyl)pyrazoles by 1,3-Dipolar Cycloaddition of the Corresponding Sydnones." Molecules 26, no. 12 (June 17, 2021): 3693. http://dx.doi.org/10.3390/molecules26123693.

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3-Arylsydnones bearing fluorine and bromine atoms on the benzene ring were synthesized from N-nitroso-2-fluorophenylglycines and characterized by NMR spectroscopy. These were employed further in synthesis of the corresponding 1-(2-fluorophenyl)pyrazoles by 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate (DMAD) as activated dipolarophile. The sydnones as reaction intermediates were characterized by single crystal X-ray diffraction analysis showing interesting features such as halogen bonding as an important interaction in modeling the crystal structure.

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29

Wang, Yongchao, Yu Chen, Shengli Duan, Yiyang Cao, Wenjin Sun, Mei Zhang, Delin Zhao, Donghua Hu, and Jianwei Dong. "Diastereoselective Three-Component 1,3-Dipolar Cycloaddition to Access Functionalized β-Tetrahydrocarboline- and Tetrahydroisoquinoline-Fused Spirooxindoles." Molecules 29, no. 8 (April 15, 2024): 1790. http://dx.doi.org/10.3390/molecules29081790.

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A chemselective catalyst-free three-component 1,3-dipolar cycloaddition has been described. The unique polycyclic THPI and THIQs were creatively employed as dipolarophiles, which led to the formation of functionalized β-tetrahydrocarboline- and tetrahydroisoquinoline-fused spirooxindoles in 60–94% of yields with excellent diastereoselectivities (10: 1−>99: 1 dr). This reaction not only realizes a concise THPI- or THIQs-based 1,3-dipolar cycloaddition, but also provides a practical strategy for the construction of two distinctive spirooxindole skeletons.

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30

Kotha, Sambasivarao, Milind Meshram, and Nageswara Panguluri. "Advanced Approaches to Post-Assembly Modification of Peptides by Transition-Metal-Catalyzed Reactions." Synthesis 51, no. 09 (March 25, 2019): 1913–22. http://dx.doi.org/10.1055/s-0037-1612418.

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We have summarized diverse synthetic approaches for the modification of peptides by employing transition-metal-catalyzed reactions. These methods can deliver unusual peptides suitable for peptidomimetics. To this end, several popular reactions such as Diels–Alder, 1,3-dipolar cycloaddition, [2+2+2] cyclotrimerization, metathesis, Suzuki–Miyaura cross-coupling, and Negishi coupling have been used to assemble modified peptides by post-assembly chemical modification strategies.1 Introduction2 Synthesis of a Cyclic α-Amino Acid Derivative via a Ring-Closing Metathesis Protocol3 Peptide Modification Using a Ring-Closing Metathesis Strategy4 Peptide Modification via a [2+2+2] Cyclotrimerization Reaction5 Peptide Modification by Using [2+2+2] Cyclotrimerization and Suzuki Coupling6 Peptide Modification via a Suzuki–Miyaura Cross-Coupling7 Peptide Modification via Cross-Enyne Metathesis and a Diels–Alder Reaction as Key Steps8 Peptide Modification via 1,3-Dipolar Cycloaddition Reactions9 Modified Peptides via Negishi Coupling10 A Modified Dipeptide via Ethyl Isocyanoacetate11 Conclusions

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31

Tao, Hongwen, Yinan Yuan, Jian Chen, Xianyong Yu, and Pinggui Yi. "Synthesis of Cholestan -3-One Derivatives Possessing a C-2 Spiro-Oxindole Substituent." Journal of Chemical Research 42, no. 1 (January 2018): 15–19. http://dx.doi.org/10.3184/174751918x15161933697781.

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A series of C-2 cholestan-3-one spiro-oxindole derivatives were prepared by the 1:3 dipolar cycloaddition reaction between the cholestan-3-one substituted by a C-2 arylidene and the azomethine ylid derived from isatin and sarcosine. The dipolarophiles were efficiently obtained by a Claisen-Schmidt reaction of cholestan-3-one and aromatic aldehydes. The structures of the products were established by a combination of NMR, high-resolution mass spectrometry (HRMS) and X-ray data analysis.

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32

PAVLOV, V. A., A. I. KURDYUKOV, V. V. PLEMENKOV, R. R. KHALIULLIN, and V. V. MOSKVA. "ChemInform Abstract: Dipolar (1 + 3)Cycloaddition Reaction of a Phosphorylnitrile Oxide with Cyclopropenes." ChemInform 26, no. 1 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199501059.

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Kidou, Chihiro, Haruki Mizoguchi, Tatsuo Nehira, and Akira Sakakura. "Enantioselective 1,3-Dipolar Cycloaddition Reaction of Nitrones with α-(Acyloxy)acroleins Catalyzed by Dipeptide-Derived Chiral Tri- or Diammonium Salts." Synlett 30, no. 15 (July 30, 2019): 1835–39. http://dx.doi.org/10.1055/s-0039-1690133.

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Organoammonium salts of dipeptide-derived chiral triamines or diamines with TfOH catalyzed the enantioselective 1,3-dipolar cycloaddition reactions of α-acyloxyacroleins with nitrones to give the corresponding adducts in good yields (up to 96%) and with high diastereo- and enantioselectivities (up to 89% ee). Although α-(p-methoxybenzoyloxy)acrolein is rather unstable under the reaction conditions, α-(3-pyrroline-1-carbonyloxy)acrolein is stable enough to be smoothly converted into the corresponding adducts with the aid of the chiral organoammonium salt catalysts.

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34

Belguedj, Roumaissa, Sofiane Bouacida, Hocine Merazig, Ali Belfaitah, Aissa Chibani, and Abdelmalek Bouraiou. "Synthesis and crystal structures of three novel benzimidazole/benzoindolizine hybrids." Zeitschrift für Naturforschung B 71, no. 3 (March 1, 2016): 231–39. http://dx.doi.org/10.1515/znb-2015-0164.

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AbstractThree benzoindolizine derivatives, 1, 2, and 3, were obtained via 1,3-dipolar cycloaddition. The reaction of 1-(2′-benzimidazolylmethyl)isoquinolinium ylides with dimethyl acetylenedicarboxylate gave a mixture of pyrrolo[2,1-a]isoquinoline-1,2-dicarboxylate (1) and 1,10b-dihydropyrrolo[2,1-a]isoquinoline-1,2-dicarboxylate (2) derivatives containing a benzimidazole moiety. The reaction of this isoquinolinium N-ylide with dimethyl maleate gave an unexpected 2,3-dihydropyrrolo[2,1-a]isoquinoline-1,2-dicarboxylate (3). The structures of all reported compounds have been examined by X-ray crystallography, mass spectrometry, and NMR spectroscopy.

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35

Sammor, Mervat S., Mustafa M. El-Abadelah, Ahmad Q. Hussein, Firas F. Awwadi, Salim S. Sabri, and Wolfgang Voelter. "A study on the reaction of 3-alkyl(aryl)imidazo[1,5-a]pyridines with ninhydrin." Zeitschrift für Naturforschung B 73, no. 6 (June 27, 2018): 413–21. http://dx.doi.org/10.1515/znb-2018-0039.

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AbstractThe reaction of 3-alkyl(aryl)imidazo[1,5-a]pyridines (1) with ninhydrin in dichloromethane at room temperature delivered good yields of the respective 2-hydroxy-2-(imidazo[1,5-a]pyridine-1-yl)indene-1,3-diones. In the presence of dimethyl acetylenedicarboxylate (DMAD), this uncatalyzed electrophilic substitution reaction, involving C-1 (in 1) and the central C=O (in ninhydrin), takes precedence over the three-component 1,4-dipolar cycloaddition reaction. This selectivity is probably due to the higher electrophilicity of the carbonyl carbon-2 in ninhydrin as compared to that of the sp-carbon atoms in DMAD, augmented with the high nucleophilicity of carbon-1 in 1.

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36

Shen, Yechen, and Younghwan Kwon. "Synthesis and Characterization of Reactive Energetic Plasticizers for Poly(glycidyl azide-co-tetramethylene glycol)-Based Polyurethane Binders." Journal of Nanoscience and Nanotechnology 21, no. 7 (July 1, 2021): 4110–15. http://dx.doi.org/10.1166/jnn.2021.19184.

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Two reactive energetic plasticizers, 3-((2,2-dinitropropoxy)methoxy)prop-1-yne and 4-((2,2-dinitropropoxy)methoxy)but-1-yne which can react with an azido-containing poly(glycidyl azide-co-tetramethylene glycol) prepolymer by cupper-free 1,3-dipolor cycloaddition (“Click”) reaction, were synthesized and characterized, in order to investigate their plasticizing performance and catalyst-free 1,3-dipolar cycloaddition reactivity on energetic polyurethane binders. Two reactive energetic plasticizers showed better plasticizing performance than commercial energetic plasticizers. In the reactivity point of view, 3-((2,2-dinitropropoxy)methoxy)prop-1-yne exhibited higher Click reactivity than 4-((2,2-dinitropropoxy)methoxy)but-1-yne. Two synthesized plasticizers were found to fulfill the requirements for use as reactive energetic plasticizers.

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37

Matsumoto, Kiyoshi, Hirokazu Iida, Takane Uchida, Yoshimi Yabe, Akikazu Kakehi, and J. William Lown. "1,3-Dipolar cycloaddition reactions of monocyclic aziridines with dimethyl 1-cyclobutene-1,2-dicarboxylate." Canadian Journal of Chemistry 72, no. 10 (October 1, 1994): 2108–17. http://dx.doi.org/10.1139/v94-268.

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The thermally induced [2 + 3] cycloadditions of certain monocyclic aziridines to dimethyl 1-cyclobutene-1,2-dicarboxylate are described. The structures of the resulting bicyclic adducts were established unambiguously by X-ray analyses. The stereochemistries of the [2 + 3] adducts were interpreted in terms of dipole–dipole interactions and secondary orbital interactions. In certain cases an initial thermal conrotatory ring opening of the cyclobutene to 2,3-di(methoxycarbonyl)-1,3-butadiene precedes the [2 + 3] cycloaddition, affording the unexpected pyrrolidine adducts 12a and 12b. The structures and stereochemistries of the latter established by X-ray analysis strongly suggest that secondary orbital interactions between the phenyl and ester groups control and stereochemistry of the reactions.

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38

Adembri, Giorgio, M. Laura Paoli, and Alessandro Sega. "Influence of the Solvent on the stereoselectivity of 1,3-Dipolar cycloaddition of Nitrile Oxides on Several 4-Substituted 2-Cyclopentenones." Journal of Chemical Research 2003, no. 3 (March 2003): 126–27. http://dx.doi.org/10.3184/030823403103173453.

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The diastereofacial selectivity in 1,3-dipolar cycloadditions of 2,6-dichlorobenzonitrile oxide on 2-cyclopentenones 1–5 is strongly dependent on the solvent when an hydroxyl group is present at C(4) (1–2) while if this group is protected (3–4) or absent (5) the reaction is solvent independent.

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39

Howell, Sarah J., Neil Spencer, and Douglas Philp. "Recognition-mediated regiocontrol of a dipolar cycloaddition reaction." Tetrahedron 57, no. 23 (June 2001): 4945–54. http://dx.doi.org/10.1016/s0040-4020(01)00402-1.

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40

Almansour, Abdulrahman I., Natarajan Arumugam, Raju Suresh Kumar, Dhaifallah M. Al-thamili, Govindasami Periyasami, Karuppiah Ponmurugan, Naif Abdullah Al-Dhabi, Karthikeyan Perumal, and Dhanaraj Premnath. "Domino Multicomponent Approach for the Synthesis of Functionalized Spiro-Indeno[1,2-b]quinoxaline Heterocyclic Hybrids and Their Antimicrobial Activity, Synergistic Effect and Molecular Docking Simulation." Molecules 24, no. 10 (May 22, 2019): 1962. http://dx.doi.org/10.3390/molecules24101962.

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An expedient synthesis of hitherto unexplored novel hybrid heterocycles comprising dispiropyrrolidine, N-styrylpiperidone and indeno[1,2-b]quinoxaline units has been developed via domino multicomponent 1,3-dipolar cycloaddition strategy employing a new class of azomethine ylide in ionic liquid, 1-butyl-3-methylimidazolium bromide. This domino protocol involves, 1,3-dipolar cycloaddition and concomitant enamine reaction affording the dispiropyrrolidine tethered N-styrylpiperidone hybrid heterocycles in moderate to good yield in a single step. These compounds were evaluated for their antimicrobial activity against bacterial and fungal pathogens, therein compounds 8f, 8h, and 8l displayed significant activity against tested microbial pathogens. The synergistic effect revealed that the combination of compound 8h with streptomycin and vancomycin exhibited potent synergistic activity against E. coli ATCC 25922. In addition, molecular docking simulation has also been studied for the most active compound.

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41

Ryan, John H., Nadia Spiccia, Leon S. M. Wong, and Andrew B. Holmes. "Synthesis of 5-Aryloxazolidines via 1,3-Dipolar Cycloaddition Reaction of a Non-Stabilized Azomethine Ylide with Aromatic Aldehydes." Australian Journal of Chemistry 60, no. 12 (2007): 898. http://dx.doi.org/10.1071/ch07282.

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The 1,3-dipolar cycloaddition reaction of a non-stabilized azomethine ylide 4a, formed in situ from N-(methoxymethyl)-N-(trimethylsilylmethyl)benzylamine 5 and a catalytic amount of trifluoroacetic acid, with aromatic aldehydes 3 gives rise to N-benzyl-5-aryloxazolidines 1. Under these conditions, 4-hydroxybenzaldehyde 3p undergoes two-fold addition of azomethine ylide 4a to afford bis adduct 11.

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42

Nguyen, Duy Trinh, Nguyen Phu Thuong Nhan, Tran Thien Hien, Nguyen Dai Hai, Dai Viet N. Vo, and Long Giang Bach. "A Simple Approach for Immobilization of Fe-Core/Au-Shell Magnetic Nanoparticles on Multi-Walled Carbon Nanotubes via Cu(I) Huisgen Cycloaddition: Preparation and Characterization." Solid State Phenomena 279 (August 2018): 187–91. http://dx.doi.org/10.4028/www.scientific.net/ssp.279.187.

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In this report, we demonstrated a novel efficient a simple strategy route for the preparation of smart hybrid Fe-core/Au-shell magnetic onto multi-walled carbon nanotubes (CNT) sidewalls via Cu (I)-catalyzed 1, 3-dipolar cycloaddition (“click” coupling). The fabrication of gold-coated iron nanoparticles (Fe@AuNPs) is initially achieved by employing a two-step reverse micelle process. A new azide terminated ligand was first synthesized to change Fe@AuNPs by ligand exchange reaction. The Fe@Au NPs decorated MWNTs (MWNTs-Fe@Au) nanohybrids were synthesized by the reaction of an azide-containing Fe@Au NPs with alkyne-functionalized MWNTs via the Cu (I)-catalyzed 1,3-dipolar cycloaddition reaction. Energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and Transmission electron microscopy (HR-TEM) were used to study the changes in surface functionalities and demonstrate the successful immobilization of Fe@Au on CNT surface. In addition, the superconducting quantum interference device (SQUID) study revealed that the nanohybrids possess superparamagnetic character which is susceptible to rapid separation under an external magnetic field.

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43

Çelebi, N., O. Çetiner, A. Güleç, and L. Türker. "1,3-Dipolar Cycloaddition Reactions of Some 1-Aryl-Pyridinium-3-Olates." Bulletin des Sociétés Chimiques Belges 102, no. 7 (September 1, 2010): 467–77. http://dx.doi.org/10.1002/bscb.19931020706.

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44

Çelebi, N., and L. Türker. "1,3-Dipolar cycloaddition reactions of some 3-aryl-phthalazinium-1-olates." Bulletin des Sociétés Chimiques Belges 102, no. 10 (September 1, 2010): 625–30. http://dx.doi.org/10.1002/bscb.19931021001.

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45

Caballero, Ruben, Pilar de la Cruz, and Fernando Langa. "(Invited) Tether-Directed Regioselective Synthesis of Bispyrazolinofullerenes." ECS Meeting Abstracts MA2023-01, no. 12 (August 28, 2023): 1263. http://dx.doi.org/10.1149/ma2023-01121263mtgabs.

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The problematic regioselective synthesis of fullerene bisadducts was finely solved by Diederich with the introduction of the tether-directed functionalization.[1] Since then, many other examples have been described, most of them using double Bingel addition or Diels-Alder cycloaddition reactions. Surprisingly, although 1,3-dipolar cycloaddition reactions are the most popular procedure for functionalization of C60, the use of this reaction for regioselective synthesis of fullerene bisadducts. Here we present our results of selective synthesis of trans-3 or e-bispirazolinofullerenes using bisnitrilimine tethered by di-tertbutylsilylbis(trifluoromethanesulfonate) group [3][4]. Further rupture of the silyl ester group allows the preparation of new derivatives for selected applications. [1] L.Isaacs, R.F.Haldimann,F.Diederich,Angew.Chem.Int.Ed.Engl.1994,33,2339. [2] F. Diederich, R. Kessinger. Acc. Chem. Res. 1999, 32, 537. [3] V. Cuesta, M. Urbani, P. de la Cruz, L. Welte, J.F. Nierengarten, F. Langa, Chem. Comm. 2016, 52, 13205 [4] R. Caballero, M. Barrejón, J. Cerdá, J. Aragó, S. Seetharaman, P. de la Cruz, E. Ortí, F. D’Souza, F. Langa. J. Am. Chem. Soc. 2021, 143, 11199. Figure 1

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46

Blanco-Carapia, Roberto E., Julio C. Flores-Reyes, Yizrell Medina-Martínez, Perla Islas-Jácome, Diego Pérez-Martínez, Leticia Lomas-Romero, Ilich A. Ibarra, Alejandro Islas-Jácome, and Eduardo González-Zamora. "Synthesis of New bis 1- and 5-Substituted 1H-Tetrazoles via Huisgen-Type 1,3-Dipolar Cycloadditions." Proceedings 9, no. 1 (April 1, 2019): 32. http://dx.doi.org/10.3390/ecsoc-22-05780.

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The synthesis and characterization of one symmetrical bis-1-substituted-1H-tetrazole (69%) via a Huisgen-type 1,3-dipolar cycloaddition, as well as, one symmetrical aza-linked bis-5-substituted-1H-tetrazole (57%) via a classic Huisgen 1,3-dipolar cycloaddition followed by a reductive aza-coupling under greener reaction conditions are described. The main reason behind these tetrazole-based ligands is to construct novel Metal-Organic Framework (MOF) architectures to evaluate their CO2 capture properties under relative humidity conditions. It is worthy to note that both herein reported products have not been synthesized nor isolated, anywhere. Besides, the synthesis of new ligands to fabricate novel MOFs with potential application in environmental remediation has become a highly valued field of opportunity for synthetic chemists and materials engineers.

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47

Cheng, Bin, Bian Bao, Bing Zu, Xiaoguang Duan, Shengguo Duan, Yun Li, and Hongbin Zhai. "Synthesis of spiro-3H-indazoles via 1,3-dipolar cycloaddition of arynes with 6-diazocyclohex-2-en-1-one derivatives and fused-2H-indazoles by subsequent rearrangement." RSC Advances 7, no. 85 (2017): 54087–90. http://dx.doi.org/10.1039/c7ra12117b.

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Rare spiro-3H-indazoles bearing a carbonyl group adjacent to the spirocyclic quarternary carbon were prepared via 1,3-dipolar cycloaddition reaction of arynes with 6-diazocyclohex-2-en-1-one derivatives under mild conditions.

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48

Goulioukina, Nataliya S., Nikolay N. Makukhin, Egor D. Shinkarev, Yuri K. Grishin, Vitaly A. Roznyatovsky, and Irina P. Beletskaya. "Base mediated 1,3-dipolar cycloaddition of α-substituted vinyl phosphonates with diazo compounds for synthesis of 3-pyrazolylphosphonates and 5-pyrazolcarboxylates." Organic & Biomolecular Chemistry 14, no. 42 (2016): 10000–10010. http://dx.doi.org/10.1039/c6ob01780k.

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49

Antol, Ivana, Zoran Glasovac, and Davor Margetić. "Mechanistic DFT Study of 1,3-Dipolar Cycloadditions of Azides with Guanidine." Molecules 28, no. 5 (March 3, 2023): 2342. http://dx.doi.org/10.3390/molecules28052342.

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Density functional calculations SMD(chloroform)//B3LYP/6-311+G(2d,p) were employed in the computational study of 1,3-dipolar cycloadditions of azides with guanidine. The formation of two regioisomeric tetrazoles and their rearrangement to cyclic aziridines and open-chain guanidine products were modeled. The results suggest the feasibility of an uncatalyzed reaction under very drastic conditions since the thermodynamically preferred reaction path (a), which involves cycloaddition by binding the carbon atom from guanidine to the terminal azide nitrogen atom, and the guanidine imino nitrogen with the inner N atom from the azide, has an energy barrier higher than 50 kcal mol−1. The formation of the other regioisomeric tetrazole (imino nitrogen interacts with terminal N atom of azide) in direction (b) can be more favorable and proceed under milder conditions if alternative activation of the nitrogen molecule releases (e.g., photochemical activation), or deamination could be achieved because these processes have the highest barrier in the less favorable (b) branch of the mechanism. The introduction of substituents should favorably affect the cycloaddition reactivity of the azides, with the greatest effects expected for the benzyl and perfluorophenyl groups.

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50

Ren, Demin, Xiaolian Hu, Yulin Huang, and Xiaofang Li. "Synthesis of Dispiro[Indeno[1,2-b]Quinoxaline-11,3′-Pyrrolizine-2′,2″-[1,3] Thiazolo[3,2-a]Pyrimidine Via Cycloaddition Reactions." Journal of Chemical Research 42, no. 9 (September 2018): 453–55. http://dx.doi.org/10.3184/174751918x15349264445767.

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The 1,3-dipolar cycloaddition reaction of ethyl 5-aryl-2-(2-methoxy-2-oxoethylidene)-7-methyl-3-oxo-2,3-dihydro-5 H-[1,3]thiazolo[3,2- a] pyrimidine-6-carboxylate and azomethine ylide, which was generated in situ by the reaction of 11 H-indeno[1,2- b]quinoxalin-11-one and L-proline, afforded novel 6″ethyl 1′-methyl 5″aryl-7″methyl-3″oxo-5’,6’,7’,7a′-tetrahydro-1' H,3″ H,5″ H-dispiro[indeno[1,2- b]quinoxaline-11, 3 ‘-pyrrolizine-2’,2″-[1,3]thiazolo[3,2- a]pyrimidine-1’,6″-dicarboxylates in good yields. The structures of all the products were characterised thoroughly by NMR, IR and HRMS together with X-ray crystallographic analysis.

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