Artykuły w czasopismach: „Tandem Cyclization”

1

Rae Kim, Hyoung, Su Yeon Jo, Hyoung Cheul Kim i Dong Ju Jeon. "Tandem Cyclization of Phytosphingosine". HETEROCYCLES 55, nr 6 (2001): 1127. http://dx.doi.org/10.3987/com-01-9187.

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2

Nookaraju, U., Eeshwaraiah Begari i Pradeep Kumar. "Total synthesis of (+)-monocerin via tandem dihydroxylation-SN2 cyclization and a copper mediated tandem cyanation–lactonization approach". Org. Biomol. Chem. 12, nr 31 (2014): 5973–80. http://dx.doi.org/10.1039/c4ob00965g.

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A simple and novel synthesis of (+)-monocerin was achieved from 3-buten-1-ol employing HKR, Julia olefination, intramolecular tandem Sharpless asymmetric dihydroxylation-S_N2 cyclization and a novel copper mediated tandem cyanation–cyclization as the key steps.

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3

Yuan, Lang, i Hai-Tao Yu. "A Density Functional Theory Investigation of the Tandem Radical Cyclization of 1-[2-Yl-3-(2-Methoxyphenyl)-prop-2-enyl]-6-oxo-1,6-dihydropyridine-2-carbonitrile". Australian Journal of Chemistry 69, nr 3 (2016): 319. http://dx.doi.org/10.1071/ch15369.

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A density functional theory investigation of the mechanism of the titled reaction has been performed. The results suggest that the compound 1-[2-iodo-3-(2-methoxyphenyl)-prop-2-enyl]-6-oxo-1,6-dihydropyridine-2-carbonitrile would rather be converted into the titled free radical by deiodination than go by way of a Diels–Alder cycloaddition and HI-elimination to access the experimentally observed product. The deiodination of the radical precursor is followed by tandem radical cyclizations and hydrogen-loss oxidations to generate tetracyclic non-radical products. The mechanism of the tandem reaction was determined by an examination of the calculated reaction barriers, attack trajectories, and interaction energies between key orbitals. Furthermore, the H-loss oxidation of the addition intermediates by several H-abstractors were carefully analyzed. The theoretical results are in close agreement with the available experimental evidence. The detailed reaction mechanism and knowledge of such an intramolecular tandem radical cyclization presented in this study not only provide insight into the nature of tandem cyclizations but also serves as a useful guide for future experimental investigations.

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4

Trost, Barry M., i Serge Mignani. "Tandem palladium-catalyzed elimination-cyclization". Journal of Organic Chemistry 51, nr 18 (wrzesień 1986): 3435–39. http://dx.doi.org/10.1021/jo00368a005.

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5

Huang, Ji-Rong, Liu Qin, Yu-Qin Zhu, Qiang Song i Lin Dong. "Multi-site cyclization via initial C–H activation using a rhodium(iii) catalyst: rapid assembly of frameworks containing indoles and indolines". Chemical Communications 51, nr 14 (2015): 2844–47. http://dx.doi.org/10.1039/c4cc07125e.

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Tandem multi-site cyclization triggered by Rh(iii)-catalyzed C–H activation has been achieved for highly efficient synthesis of spirocycle indolin-3-one (C2-cyclization), benzo[a]carbazole (C3-cyclization) and an unusual indoxyl core (N1-cyclization).

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6

Cao, Ziping, Shan Li, Jie Li, Xin Meng, Huaqing Zhang, Xuejun Sun i Jinmao You. "Gold-catalyzed π-directed regioselective cyclization of bis(o-alkynyl benzyl alcohols): rapid access to dihydroisobenzofuran derivatives". New Journal of Chemistry 40, nr 10 (2016): 8211–15. http://dx.doi.org/10.1039/c6nj02066f.

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7

Huo, Xing, Jizhong Fang, Lige Xu i Bowen Fang. "Synergistic Oxidative Coupling–[3+2] Cyclization of Quinones with Olefins Promoted by Cerium(IV) Sulfate Tetrahydrate". Synlett 28, nr 12 (11.04.2017): 1491–95. http://dx.doi.org/10.1055/s-0036-1588781.

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A cerium(IV) sulfate tetrahydrate promoted oxidative cyclization of quinones with olefins is developed. It proceeds through a tandem [3+2]-cyclization–oxidative coupling–[3+2]-cyclization process, in which tetrahydrobenzodifurans were conveniently constructed in high yields. Moreover, this method exhibits a good functional-group tolerance and scalability.

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8

Błocka, Aleksandra, Paweł Woźnicki, Marek Stankevič i Wojciech Chaładaj. "Pd-catalyzed intramolecular addition of active methylene compounds to alkynes with subsequent cross-coupling with (hetero)aryl halides". RSC Advances 9, nr 68 (2019): 40152–67. http://dx.doi.org/10.1039/c9ra08002c.

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A tandem cyclization/coupling of acetylenic active methylene compounds with aryl halides features broad scope and excellent functional group compatibility. Mechanistic studies identified 5-exo-dig cyclization as the rate limiting step.

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9

Hou, Yunlei, Mingze Qin, Xiuxiu Yang, Qi Shen, Yanfang Zhao, Yajing Liu i Ping Gong. "Palladium-catalyzed three-component tandem cyclization of buta-2,3-dien-1-ol, aryl iodides, and imines: an efficient protocol for the synthesis of oxazolidine derivatives". RSC Advances 7, nr 12 (2017): 7401–5. http://dx.doi.org/10.1039/c6ra27993g.

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An efficient three-component tandem cyclization reaction for the synthesis of highly substituted oxazolidines was achieved through the Pd⁰-catalyzed cyclization of buta-2,3-dien-1-ol with aryl iodides and imines.

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10

Deng, Danfeng, Dayun Huang, Xiangyu Sun i Biwen Gao. "Recent Advances in the Tandem Difunctionalization of Alkynes: Mechanism-Based Classification". Synthesis 53, nr 19 (19.04.2021): 3522–34. http://dx.doi.org/10.1055/a-1486-2158.

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AbstractRecent advances on the tandem difunctionalization of alkynes in the last decade (2010–2020) are summarized into five categories based on the type of mechanism: (1) radical addition and coupling for the synthesis of polysubstituted ketones and alkenes, (2) electrophilic addition of alkynes, (3) reactions mediated by haloalkynes or copper acetylides, (4) the preparation of cyclic compounds via radical processes, palladium-catalyzed reactions or conjugate additions, and (5) cyclic compounds as intermediates in ring openings. Herein, radical, electrophilic and nucleophilic reactions are discussed in detail. We hope this review will help to promote future research in this area. 1 Introduction2 Radical Addition and Coupling3 Electrophilic Addition4 Reactions Mediated by Haloalkynes or Copper Acetylides5 Cyclization6 Cyclization and Ring Opening7 Conclusions

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11

Oguri, Hiroki, Haruki Mizoguchi, Hideaki Oikawa, Aki Ishiyama, Masato Iwatsuki, Kazuhiko Otoguro i Satoshi Ōmura. "Parallel and four-step synthesis of natural-product-inspired scaffolds through modular assembly and divergent cyclization". Beilstein Journal of Organic Chemistry 8 (22.06.2012): 930–40. http://dx.doi.org/10.3762/bjoc.8.105.

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By emulating the universal biosynthetic strategy, which employs modular assembly and divergent cyclizations, we have developed a four-step synthetic process to yield a collection of natural-product-inspired scaffolds. Modular assembly of building blocks onto a piperidine-based manifold6, having a carboxylic acid group, was achieved through Ugi condensation,N-acetoacetylation and diazotransfer, leading to cyclization precursors. The rhodium-catalyzed tandem cyclization and divergent cycloaddition gave rise to tetracyclic and hexacyclic scaffolds by the appropriate choice of dipolarophiles installed at modules 3 and 4. A different piperidine-based manifold15bearing an amino group was successfully applied to demonstrate the flexibility and scope of the unified four-step process for the generation of structural diversity in the fused scaffolds. Evaluation of in vitro antitrypanosomal activities of the collections and preliminary structure–activity relationship (SAR) studies were also undertaken.

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12

Roy, Snigdha. "Prins-Friedel-Crafts Cyclization: Synthesis of Diversely Functionalized Six- Membered Oxacycles". Current Organic Chemistry 25, nr 5 (15.03.2021): 635–51. http://dx.doi.org/10.2174/1385272825666210114105020.

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Prins cyclization is a well-established synthetic protocol to generate a wide range of important oxygen heterocycles. It is a cyclization reaction performed by an oxocarbenium ion that undergoes an intramolecular pi-bond attack to construct a new carbon-carbon bond. When this cyclization process is conjugated with Friedel-Crafts reaction, it further expands the synthetic potential by fabricating two different carbon-carbon bonds in one single reaction. Different acid catalysts mediated the coupled Prins-Friedel-Crafts reaction which is conducted both in stepwise as well as in tandem fashion. In the stepwise route, three different reacting components were utilized whereas, the tandem methodology required proper modification of the initial substrate molecule. An array of allylic, propargylic, other related alkenols, and carbonyl reactants were employed to carry out the cyclization process. Several oxygenated heterocycles equipped with diverse functionalities were constructed in a stereoselective manner which again reinforced the significance of this cyclization protocol undoubtedly. The present mini-review highlights the utilization of different one-pot stepwise Prins-Friedel-Crafts reactions and the subsequent development of cascade Prins- Friedel-Crafts cyclization process to furnish intricate molecular architectures of vital six-membered oxacycles.

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13

Aronica, Laura, i Gianluigi Albano. "Cyclization Reactions for the Synthesis of Phthalans and Isoindolines". Synthesis 50, nr 06 (31.01.2018): 1209–27. http://dx.doi.org/10.1055/s-0037-1609175.

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Oxygen and nitrogen heterocycles are present in a vast number of natural substrates and biologically active molecules. In particular, phthalan and isoindoline subunits are found in many classes of products such as antibiotics, antioxidants, antimycotics, pigments, and fluorophores. Therefore several procedures dedicated to the construction of these heterocycles have been developed. In this review, a detailed analysis of the literature data regarding the synthesis of these nuclei via cyclization reactions is reported.1 Introduction2 Phthalans2.1 Oxa-Pictet–Spengler Reaction2.2 Garratt–Braverman Cyclization2.3 Diels–Alder and Related Reactions2.4 [2+2+2] Cyclotrimerization of Alkynes2.5 Cycloetherification of ortho-Substituted Aromatics2.6 Tandem Carbonylative Sonogashira Coupling–Cyclization Reactions3 Isoindolines3.1 Amination of Dihalides3.2 Intramolecular Hydroamination3.3 Diels–Alder and Related Reactions3.4 [2+2+2] Cycloaddition Reactions3.5 Tandem Carbonylative Sonogashira Coupling–Cyclization Reactions4 Conclusions

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14

Zhang, Wei, Wenlong Yu, Qiangqiang Yan, Zhanxiang Liu i Yuhong Zhang. "Synthesis of substituted oxazoles via Pd-catalyzed tandem oxidative cyclization". Organic Chemistry Frontiers 4, nr 12 (2017): 2428–32. http://dx.doi.org/10.1039/c7qo00517b.

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15

Pan, Yixiao, Changjun Chen, Xin Xu, Haoqiang Zhao, Jiahong Han, Huanrong Li, Lijin Xu, Qinghua Fan i Jianliang Xiao. "Metal-free tandem cyclization/hydrosilylation to construct tetrahydroquinoxalines". Green Chemistry 20, nr 2 (2018): 403–11. http://dx.doi.org/10.1039/c7gc03095a.

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B(C₆F₅)₃-Catalyzed tandem cyclization/hydrosilylation for the step-economical construction of 1,2,3,4-tetrahydroquinoxalines from readily available starting materials has been developed.

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16

Bailey, William F., i Timo V. Ovaska. "Tandem Cyclization of Enynyl and Diynyl Alkyllithiums". Chemistry Letters 22, nr 5 (maj 1993): 819–20. http://dx.doi.org/10.1246/cl.1993.819.

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17

Choi, Kyoungmin, Jung Min Joo i Chulbom Lee. "Rhodium-catalyzed tandem addition–cyclization of alkynylimines". Tetrahedron 71, nr 35 (wrzesień 2015): 5910–17. http://dx.doi.org/10.1016/j.tet.2015.05.009.

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18

Bailey, William F., i Kyllikki Rossi. "Tandem anionic cyclization approach to polycarbocyclic products". Journal of the American Chemical Society 111, nr 2 (styczeń 1989): 765–66. http://dx.doi.org/10.1021/ja00184a073.

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19

Kariv-Miller, Essie, Hatsuo Maeda i Franco Lombardo. "Reductive tandem cyclization of allyl pentenyl ketones". Journal of Organic Chemistry 54, nr 17 (sierpień 1989): 4022–24. http://dx.doi.org/10.1021/jo00278a007.

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20

Ghosh, Tirthankar, i Harold Hart. "Scope of tandem cycloadditon/radical cyclization methodology". Journal of Organic Chemistry 54, nr 21 (październik 1989): 5073–85. http://dx.doi.org/10.1021/jo00282a022.

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21

Ohno, Hiroaki, Kumiko Miyamura, Yusuke Takeoka i Tetsuaki Tanaka. "Palladium(0)-Catalyzed Tandem Cyclization of Allenenes". Angewandte Chemie International Edition 42, nr 23 (16.06.2003): 2647–50. http://dx.doi.org/10.1002/anie.200351011.

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22

Curran, DP, i SN Sun. "Tandem Radical Cyclizations: a One-Step Synthesis of Stereoisomeric Tricyclo[6.3.0.02,6]undecanes From Acyclic Precursors". Australian Journal of Chemistry 48, nr 2 (1995): 261. http://dx.doi.org/10.1071/ch9950261.

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Radical cyclization of (1E,5Z)-1-iodoundeca-1,5,10-triene with triphenyltin hydride provides one acyclic, one monocyclic, two bicyclic and four tricyclic products. At low concentration (0.002 M), the title tricycloundecane products resulting from triple cyclization predominate, but the stereoselectivity is low. Cyclization of (1E,5Z)-1-iodo-8,8-bis( phenylsulfonyl )undeca-1,5,10-triene followed by reductive desulfonylation provides a similar ratio of products to the parent. The results show that this class of triple cyclization occurs well, but the level of stereoselectivity must be raised for it to become synthetically useful.

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23

Barrionuevo, Cecilia A., Luciana C. Schmidt i Juan E. Argüello. "Unexpected formation of 4,4-dimethyl-1,2-disubstituted-dicarbonyl cyclopentanes from ketone enolate anions and 1,3-diiodo-2,2-dimethylpropane". New Journal of Chemistry 40, nr 5 (2016): 4550–55. http://dx.doi.org/10.1039/c5nj03672k.

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24

Wang, Liang, Xuehu Li, Hua Tao, Xiang Zhou, Xihong Lu, Wenyue Du, Tingting Jiang, Zhijun Xin i Jianping Liang. "Palladium-catalyzed intermolecular tandem cyclization reaction: a highly regioselective synthesis of functionalized 3H-spiro[isobenzofuran-1,3′-isochroman] scaffolds". Organic & Biomolecular Chemistry 15, nr 11 (2017): 2403–10. http://dx.doi.org/10.1039/c6ob02802k.

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25

Zhu, Xiaoyan, Feng Liu, Xinwu Ba i Yonggang Wu. "Tandem Suzuki Polymerization/Heck Cyclization Reaction to Form Ladder-Type 9,9′-Bifluorenylidene-Based Conjugated Polymer". Polymers 15, nr 16 (10.08.2023): 3360. http://dx.doi.org/10.3390/polym15163360.

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The synthesis of ladder-type 9,9′-bifluorenylidene-based conjugated polymer is reported. Unlike the typical synthetic strategy, the new designed ladder-type conjugated polymer is achieved via tandem Suzuki polymerization/Heck cyclization reaction in one-pot. In the preparation process, Suzuki polymerization reaction occurred first and then the intramolecular Heck cyclization followed smoothly under the same catalyst Pd(PPh3)4. The model reaction proved that the introduction of iodine (I) for this tandem reaction can effectively control the sequential bond-forming process and inhibit the additional competitive side reactions. Thus, small-molecule model compounds could be obtained in high yields. The successes of the synthesized small molecule and polymer compounds indicate that the Pd-catalyzed tandem reaction may be an effective strategy for improving extended π-conjugated materials.

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26

Zheng, Dongsong, Qiankun Zhao, Xiaoying Hu, Tanyu Cheng, Guohua Liu i Wei Wang. "A dynamic kinetic asymmetric transfer hydrogenation–cyclization tandem reaction: an easy access to chiral 3,4-dihydro-2H-pyran-carbonitriles". Chemical Communications 53, nr 45 (2017): 6113–16. http://dx.doi.org/10.1039/c7cc02156a.

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27

Grissom, Janet Wisniewski, Trevor L. Calkins, Dahai Huang i Heidi McMillen. "High temperature radical cyclization anomalies in the tandem enediyne-bis-radical cyclization". Tetrahedron 50, nr 16 (kwiecień 1994): 4635–50. http://dx.doi.org/10.1016/s0040-4020(01)85004-3.

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28

Morikawa, Tsutomu, Tohru Nishiwaki i Yoshiro Kobayashi. "Radical cyclization to the trifluoromethyl-substituted double bond: Regioselectivity and tandem cyclization". Tetrahedron Letters 30, nr 18 (1989): 2407–10. http://dx.doi.org/10.1016/s0040-4039(01)80412-3.

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29

Álvarez, Estela, Delia Miguel, Patricia García-García, Manuel A. Fernández-Rodríguez, Félix Rodríguez i Roberto Sanz. "Solvent- and ligand-induced switch of selectivity in gold(I)-catalyzed tandem reactions of 3-propargylindoles". Beilstein Journal of Organic Chemistry 7 (9.06.2011): 786–93. http://dx.doi.org/10.3762/bjoc.7.89.

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The selectivity of our previously described gold-catalyzed tandem reaction, 1,2-indole migration followed by aura-iso-Nazarov cyclization, of 3-propargylindoles bearing (hetero)aromatic substituents at both the propargylic and terminal positions, was reversed by the proper choice of the catalyst and the reaction conditions. Thus, 3-(inden-2-yl)indoles, derived from an aura-Nazarov cyclization (instead of an aura-iso-Nazarov cyclization), were obtained in moderate to good yields from a variety of 3-propargylindoles.

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30

Chen, Junjie, Xiuling Han i Xiyan Lu. "Palladium(ii)-catalyzed tandem cyclization of 2-ethynylaniline tethered cinnamyl acetate for the synthesis of indenoindoles". Organic & Biomolecular Chemistry 18, nr 43 (2020): 8850–53. http://dx.doi.org/10.1039/d0ob01975e.

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31

Luo, Yanlong, Huaming Sun, Weiqiang Zhang, Xiu Wang, Shan Xu, Guofang Zhang, Yajun Jian i Ziwei Gao. "Triple zirconocene/brønsted acid/CuO cooperative and relay catalysis system for tandem Mannich addition/C–C formative cyclization/oxidation". RSC Advances 7, nr 46 (2017): 28616–25. http://dx.doi.org/10.1039/c7ra00870h.

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32

Zhang, Wen-Xiong, Ling Xu i Zhenfeng Xi. "Recent development of synthetic preparation methods for guanidines via transition metal catalysis". Chemical Communications 51, nr 2 (2015): 254–65. http://dx.doi.org/10.1039/c4cc05291a.

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33

Giofrè, Salvatore V., Roberto Romeo, Raffaella Mancuso, Nicola Cicero, Nicola Corriero, Ugo Chiacchio, Giovanni Romeo i Bartolo Gabriele. "A new microwave-assisted thionation-heterocyclization process leading to benzo[c]thiophene-1(3H)-thione and 1H-isothiochromene-1-thione derivatives". RSC Advances 6, nr 25 (2016): 20777–80. http://dx.doi.org/10.1039/c6ra01329e.

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34

Tyagi, Akshi, Noor U. Din Reshi, Prosenjit Daw i Jitendra K. Bera. "Palladium complexes with an annellated mesoionic carbene (MIC) ligand: catalytic sequential Sonogashira coupling/cyclization reaction for one-pot synthesis of benzofuran, indole, isocoumarin and isoquinolone derivatives". Dalton Transactions 49, nr 43 (2020): 15238–48. http://dx.doi.org/10.1039/d0dt02918a.

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35

Yao, Hai-Feng, Dian-Liang Wang, Fang-Hui Li, Bing Wu, Zhong-Jian Cai i Shun-Jun Ji. "Synthesis of organoselenyl isoquinolinium imides via iron(iii) chloride-mediated tandem cyclization/selenation of N′-(2-alkynylbenzylidene)hydrazides and diselenides". Organic & Biomolecular Chemistry 18, nr 38 (2020): 7577–84. http://dx.doi.org/10.1039/d0ob01517b.

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36

Gao, Yu-Qi, Yi Hou, Liming Zhu, Junhan Chen, Ruoxin Li, Sheng-Yong Zhang, Yu-Peng He i Weiqing Xie. "Visible-light driven synthesis of polycyclic benzo[d][1,3]oxazocine from 2-aminochalcone". Chemical Communications 56, nr 49 (2020): 6739–42. http://dx.doi.org/10.1039/d0cc02416c.

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37

Zhao, Shangkun, Yuanyuan Zhu, Minli Zhang, Xixi Song i Junbiao Chang. "Base-Mediated Tandem 1,6-Addition/Cyclization/Isomerization Reactions between para-Quinone Methides and Benzyl Chlorides: Approaches to Diverse Frameworks at Each Cascade Stage". Synthesis 51, nr 10 (19.02.2019): 2136–48. http://dx.doi.org/10.1055/s-0037-1610691.

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Base-mediated stereospecific tandem reactions using para-quinone methides and carbene-like benzyl chlorides are developed. DBU-mediated 1,6-addition/cyclization/isomerization reactions produce triarylsubstituted alkenes in 43–89% yields and Z/E ratios of 5:1 to 35:1 in favor of the Z-isomers. Single-step 1,6-conjugate additions are realized with the mediation of cesium carbonate, and different triaryl chloroethanes are obtained in yields of 41–54% and excellent diastereoselectivities of more than 20:1. In addition, tandem 1,6-addition/cyclization reactions are achieved using tuned 2,4-disubstituted benzyl chlorides to afford diaryl spirocyclopropyl para-dienones in yields of 35–83% and diastereoselectivities of more than 20:1 in favor of the anti-isomers. The transformations from triaryl chloroethanes and spirocyclopropyl para-dienones into triarylsubstituted alkenes are also demonstrated to support the proposed tandem mechanisms.

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38

Yamamoto, Yasutomo, Tatsuya Yamaguchi, Atsunori Kaneshige, Aiko Hashimoto, Sachiho Kaibe, Akari Miyawaki, Ken-ichi Yamada i Kiyoshi Tomioka. "Consecutive Aminolithiation–Carbolithiation of a Linear Aminoalkene Bearing Terminal Vinyl Sulfide Moiety to Give Hydroindolizine". Synlett 28, nr 20 (8.08.2017): 2913–17. http://dx.doi.org/10.1055/s-0036-1588522.

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Aminolithiation–carbolithiation tandem cyclization of an aminoalkene bearing vinyl sulfide moiety proceeded smoothly using stoichiometric amounts of BuLi. Both aminolithiation and carbolithiation were in equilibrium at room temperature, and the stereochemistry of the cyclization was thermodynamically controlled. At –78 °C the reaction was kinetically controlled and the cyclized product, 1,2-disubstituted octahydroindolizine, was obtained with good diastereoselectivity.

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39

Gu, Zheng-Yang, i Ji-Bao Xia. "[3 + 1 + 1] cyclization of vinyl oxiranes with azides and CO by tandem palladium catalysis: efficient synthesis of oxazolidinones". Organic Chemistry Frontiers 8, nr 15 (2021): 4112–17. http://dx.doi.org/10.1039/d1qo00591j.

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40

Wang, Chaofan, Ling Fang, Lingling Zhang, Ya Wang, Fang Gao i Zhiyong Wang. "Base-mediated unprecedented tandem cyclization reaction of nitrilimines and sulfur ylides: facile approaches to multifunctionalized pyrazolines". Organic Chemistry Frontiers 9, nr 8 (2022): 2204–8. http://dx.doi.org/10.1039/d2qo00232a.

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41

Jiang, Shuai-Shuai, Yu-Ting Xiao, Yan-Chen Wu, Shu-Zheng Luo, Ren-Jie Song i Jin-Heng Li. "Manganese(iii)-promoted tandem phosphinoylation/cyclization of 2-arylindoles/2-arylbenzimidazoles with disubstituted phosphine oxides". Organic & Biomolecular Chemistry 18, nr 25 (2020): 4843–47. http://dx.doi.org/10.1039/d0ob00877j.

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42

Behera, Harekrushna, Venkatachalam Ramkumar i Nandita Madhavan. "Triamide macrocyclic chloride receptors via a one-pot tandem reduction–condensation–cyclization reaction". Organic & Biomolecular Chemistry 15, nr 23 (2017): 4937–40. http://dx.doi.org/10.1039/c7ob00642j.

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43

Mou, Xue-Qing, Zheng-Liang Xu, Shao-Hua Wang, Dao-Yong Zhu, Jie Wang, Wen Bao, Shi-Jiang Zhou, Chao Yang i Di Zhang. "An Au(i)-catalyzed rearrangement/cyclization cascade toward the synthesis of 2-substituted-1,4,5,6-tetrahydrocyclopenta[b]pyrrole". Chemical Communications 51, nr 60 (2015): 12064–67. http://dx.doi.org/10.1039/c5cc03979g.

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44

Li, Yonghong, Yuanyuan Zhu i Shang-Dong Yang. "Visible-light-induced tandem phosphorylation cyclization of vinyl azides under mild conditions". Organic Chemistry Frontiers 5, nr 5 (2018): 822–26. http://dx.doi.org/10.1039/c7qo01004d.

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45

Kiamehr, Mostafa, Firouz Matloubi Moghaddam, Satenik Mkrtchyan, Volodymyr Semeniuchenko, Linda Supe, Alexander Villinger, Peter Langer i Viktor O. Iaroshenko. "Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts". Beilstein Journal of Organic Chemistry 9 (10.06.2013): 1119–26. http://dx.doi.org/10.3762/bjoc.9.124.

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The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.02,7]trideca-2(7),11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of the 1,3-dicarbonyl unit to 4-position of the pyridinium salt and subsequent cyclization by base-assisted proton migration and nucleophilic addition of the oxygen atom to the 2-position, as was elucidated by DFT computations. Fairly extensive screening of bases and additives revealed that the presence of potassium cations is essential for formation of the product.

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Fan, Jian, Shengke Wang, Jiahui Chen, Manyi Wu, Jitan Zhang i Meihua Xie. "Synthesis of 2-acetyl trisubstituted furans via copper-mediated deacylation cleavage of unstrained C(sp3)–C(sp2) bonds". Organic Chemistry Frontiers 6, nr 4 (2019): 437–41. http://dx.doi.org/10.1039/c8qo01139g.

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Mahapatra, Ajit Kumar, Kalipada Maiti, Saikat Kumar Manna, Rajkishor Maji, Sanchita Mondal, Chitrangada Das Mukhopadhyay, Prithidipa Sahoo i Debasish Mandal. "A cyclization-induced emission enhancement (CIEE)-based ratiometric fluorogenic and chromogenic probe for the facile detection of a nerve agent simulant DCP". Chemical Communications 51, nr 47 (2015): 9729–32. http://dx.doi.org/10.1039/c5cc02991k.

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Padwa, A. "Tandem methodology for heterocyclic synthesis". Pure and Applied Chemistry 76, nr 11 (1.01.2004): 1933–52. http://dx.doi.org/10.1351/pac200476111933.

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Tandem methodology for heterocyclic synthesis represents a powerful approach for the rapid buildup of molecular complexity from potentially simple starting materials. Work from our laboratory has shown that the rhodium(II)-catalyzed cyclization cascade of alpha-diazo imides represents an effective method for the synthesis of a variety of heterocyclic systems. As an extension of these studies, we became interested in using a linked Pummerer/N-acyliminium ion cyclization sequence since we felt that this combination offers unique opportunities for the assemblage of complex target molecules. A synthetic method that combines transformations of different reaction types significantly broadens the scope of such procedures in synthetic chemistry. Alpha-thiocarbocations generated from the Pummerer reaction of beta-phenylsulfinylmethyl-alpha, beta-unsaturated amides can be intercepted by the adjacent amido group to produce transient amino-substituted furans which undergo subsequent Diels–Alder cycloadditions. Using this domino amido Pummerer/Diels–Alder cascade, we were able to assemble novel polycyclic systems in a single operation. The key step in the process involves the generation of a reactive N-acyliminium ion by fragmentation of an amino-substituted [4+2]-cycloadduct. The successful synthesis of a number of alkaloids by this sequence of reactions reveals the usefulness and importance of this unique domino cascade. Application of the process for the preparation of the stenoma alkaloid stenine was recently carried out in our laboratory.

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Peng, Haiyun, Yinbo Wan, Yu Zhang i Guisheng Deng. "Synthesis of 2-alkenylfurans via a Ag(i)-catalyzed tandem cyclization/cross-coupling reaction of enynones with iodonium ylides". Chemical Communications 56, nr 9 (2020): 1417–20. http://dx.doi.org/10.1039/c9cc08561k.

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Mai, Wen-Peng, Fei Wang, Xiao-Feng Zhang, Shi-Min Wang, Qun-Peng Duan i Kui Lu. "Nickel-catalysed radical tandem cyclisation/arylation: practical synthesis of 4-benzyl-3,3-difluoro-γ-lactams". Organic & Biomolecular Chemistry 16, nr 35 (2018): 6491–98. http://dx.doi.org/10.1039/c8ob01389f.

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