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Journal articles on the topic 'Alkynes'

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Author: Grafiati

Published: 4 June 2021

Last updated: 31 July 2024

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1

Sewald, Norbert, and Klaus Burger. "α-Trifluormethylsubstituierte α-Hydroxysäuren mit Alkinfunktionen in der Seitenkette / α-Trifluoromethyl Substituted α-Hydroxy Acids with Alkyne Functions in the Side Chain." Zeitschrift für Naturforschung B 45, no. 6 (June 1, 1990): 871–75. http://dx.doi.org/10.1515/znb-1990-0619.

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Trifluoromethyl substituted α-hydroxy acids with alkyne functions in the side chain are obtained on reaction of trifluoro pyruvates with alkynyl Grignard reagents and alkali metal salts of alkynes, respectively.

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2

Matsumura, Mio, Kaho Tsukada, Kiwa Sugimoto, Yuki Murata, and Shuji Yasuike. "Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes." Beilstein Journal of Organic Chemistry 18 (July 19, 2022): 863–71. http://dx.doi.org/10.3762/bjoc.18.87.

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Alkynyl selenides have attracted considerable research interest recently, owing to their applications in the biological and pharmaceutical fields. The Cu-catalyzed tandem reaction for the synthesis of novel alkynyl imidazopyridinyl selenides is presented. A one-pot synthesis route afforded alkynyl imidazopyridinyl selenides in moderate to good yields. This was achieved by a two-step reaction between terminal alkynes and diimidazopyridinyl diselenides, generated from imidazo[1,2-a]pyridines and Se powder, using 10 mol % of CuI and 1,10-phenanthroline as the catalytic system under aerobic conditions. The C(sp2)–Se and C(sp)–Se bond-formation reaction can be performed in one-pot by using inexpensive and easy to handle Se powder as the Se source. The reaction proceeded with terminal alkynes having various substitutions, such as aryl, vinyl, and alkyl groups. The obtained alkynyl imidazopyridinyl selenide was found to undergo nucleophilic substitution reaction on Se atom using organolithium reagents and 1,3-dipolar azide–alkyne cycloaddition based on the alkyne moiety.

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3

Cheng, Jiang, Bingbing Wang, and Song Sun. "The n-dig-Cyclization (n = 5, 6) of Alkynes Involving Fixation of CO2." Synlett 29, no. 14 (June 11, 2018): 1814–22. http://dx.doi.org/10.1055/s-0037-16110021.

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Being an abundant, easily available, and renewable one-carbon source, carbon dioxide has received much attention in organic synthesis. However, carbon dioxide is a thermodynamically inert molecule that is hard to incorporate into useful chemicals. Nevertheless, various elegant methods have been developed for the incorporation of carbon dioxide in a number of heterocycles. In this review, we summarize and update the recent advances in n-dig-cyclization of alkynes involving the fixation of CO2, including the 5-dig- and 6-dig-cyclization of alkynes.1 Introduction2 The 5-dig-Cyclization of Alkynes3 The 6-dig-Cyclization of Alkynes4 Conclusion

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4

Alabugin, Igor, Edgar Gonzalez-Rodriguez, Rahul Kawade, Aleksandr Stepanov, and Sergei Vasilevsky. "Alkynes as Synthetic Equivalents of Ketones and Aldehydes: A Hidden Entry into Carbonyl Chemistry." Molecules 24, no. 6 (March 15, 2019): 1036. http://dx.doi.org/10.3390/molecules24061036.

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The high energy packed in alkyne functional group makes alkyne reactions highly thermodynamically favorable and generally irreversible. Furthermore, the presence of two orthogonal π-bonds that can be manipulated separately enables flexible synthetic cascades stemming from alkynes. Behind these “obvious” traits, there are other more subtle, often concealed aspects of this functional group’s appeal. This review is focused on yet another interesting but underappreciated alkyne feature: the fact that the CC alkyne unit has the same oxidation state as the -CH2C(O)- unit of a typical carbonyl compound. Thus, “classic carbonyl chemistry” can be accessed through alkynes, and new transformations can be engineered by unmasking the hidden carbonyl nature of alkynes. The goal of this review is to illustrate the advantages of using alkynes as an entry point to carbonyl reactions while highlighting reports from the literature where, sometimes without full appreciation, the concept of using alkynes as a hidden entry into carbonyl chemistry has been applied.

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5

Balamurugan, Rengarajan, Naganaboina Naveen, Seetharaman Manojveer, and Masthan Vali Nama. "Homo and Heterocoupling of Terminal Alkynes Using Catalytic CuCl2 and DBU." Australian Journal of Chemistry 64, no. 5 (2011): 567. http://dx.doi.org/10.1071/ch11080.

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Homocoupling of terminal alkynes has been efficiently achieved using catalytic amounts of CuCl2 and DBU. This methodology could be extended to couple two different terminal alkynes together by taking one of the alkyne partners, preferably the electron rich alkyne, in five fold excess than the other.

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6

Jover, Jesús. "Copper-Catalyzed Eglinton Oxidative Homocoupling of Terminal Alkynes: A Computational Study." Journal of Chemistry 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/430358.

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The copper(II) acetate mediated oxidative homocoupling of terminal alkynes, namely, the Eglinton coupling, has been studied with DFT methods. The mechanism of the whole reaction has been modeled using phenylacetylene as substrate. The obtained results indicate that, in contrast to some classical proposals, the reaction does not involve the formation of free alkynyl radicals and proceeds by the dimerization of copper(II) alkynyl complexes followed by a bimetallic reductive elimination. The calculations demonstrate that the rate limiting-step of the reaction is the alkyne deprotonation and that more acidic substrates provide faster reactions, in agreement with the experimental observations.

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7

Schumacher, Ricardo F., Benhur Godoi, Carla K. Jurinic, and Andrei L. Belladona. "Diorganyl Dichalcogenides and Copper/Iron Salts: Versatile Cyclization System To Achieve Carbo- and Heterocycles from Alkynes." Synthesis 53, no. 15 (March 24, 2021): 2545–58. http://dx.doi.org/10.1055/a-1463-4098.

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AbstractOrganochalcogen-containing cyclic molecules have shown several promising pharmacological properties. Consequently, different strategies have been developed for their synthesis in the past few years. Particularly due to the low cost and environmental aspects, copper- and iron-promoted cyclization reactions of alkynyl substrates have been broadly and efficiently applied for this purpose. This short review presents an overview of the most recent advances in the synthesis of organochalcogen-containing carbo- and heterocycles by reacting diorganyl disulfides, diselenides, and ditellurides with alkyne derivatives in the presence of copper and iron salts to promote cyclization reactions.1 Introduction2 Synthesis of Carbo- and Heterocycles via Reactions of Alkynes with Diorganyl Dichalcogenides and Copper Salts3 Synthesis of Carbo- and Heterocycles via Reactions of Alkynes with Diorganyl Dichalcogenides and Iron Salts4 Conclusions

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8

Davenel, Vincent, Chloé Puteaux, Christian Nisole, Fabien Fontaine-Vive, Jean-Marie Fourquez, and Véronique Michelet. "Indium-Catalyzed Cycloisomerization of 1,6-Cyclohexenylalkynes." Catalysts 11, no. 5 (April 24, 2021): 546. http://dx.doi.org/10.3390/catal11050546.

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Efficient four- and five-step routes to access functionalized bicyclo[3.2.1]oct-2-ene and bicyclo[3.3.1]nonadiene via indium-mediated cycloisomerization of 1,6-enynes has been developed. This atom-economical catalytic process was optimized and relied on the efficiency of InCl3 leading to the preparation of functionalized bicyclic adducts in up to 99% isolated yield. The cyclization occurred on two different processes (5-exo versus 6-endo pathway) and were influenced by the substitution of the alkynyl moiety. The exo process was favored for non-substituted alkynes whereas the endo pathway was generally observed for substituted alkynes. Then, the presence of electron-withdrawing groups on the aryl substituted alkyne increased the ratio of the exo isomer. DFT calculations were performed on stability of intermediates and corroborated the intervention of InCl3.

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9

Chotana, Ghayoor A., Jose R. Montero Bastidas, Susanne L. Miller, Milton R. Smith, and Robert E. Maleczka. "One-Pot Iridium Catalyzed C–H Borylation/Sonogashira Cross-Coupling: Access to Borylated Aryl Alkynes." Molecules 25, no. 7 (April 10, 2020): 1754. http://dx.doi.org/10.3390/molecules25071754.

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Borylated aryl alkynes have been synthesized via one-pot iridium catalyzed C–H borylation (CHB)/Sonogashira cross-coupling of aryl bromides. Direct borylation of aryl alkynes encountered problems related to the reactivity of the alkyne under CHB conditions. However, tolerance of aryl bromides to CHB made possible a subsequent Sonogashira cross-coupling to access the desired borylated aryl alkynes.

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10

Yang, Shuliang, Changyan Cao, Li Peng, Jianling Zhang, Buxing Han, and Weiguo Song. "A Pd–Cu2O nanocomposite as an effective synergistic catalyst for selective semi-hydrogenation of the terminal alkynes only." Chemical Communications 52, no. 18 (2016): 3627–30. http://dx.doi.org/10.1039/c6cc00143b.

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A new type lead-free Pd–Cu₂O nanocomposite catalyst shows “double” selectivities for hydrogenation of alkynes: only terminal alkynes hydrogenated and only alkenes produced, i.e. no internal alkyne is hydrogenated.

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11

Gao, Yuan, Michael C. Jennings, and Richard J. Puddephatt. "Hydrogen transfer from formic acid to alkynes catalyzed by a diruthenium complex." Canadian Journal of Chemistry 79, no. 5-6 (May 1, 2001): 915–21. http://dx.doi.org/10.1139/v00-169.

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The diruthenium(0) complex [Ru2(µ-CO)(CO)4(µ-dppm)2] (1) (dppm = Ph2PCH2PPh2), is a catalyst for the transfer hydrogenation, using formic acid as hydrogen donor, of the alkynes PhCºCPh, PhCºCMe, EtCºCEt, and PrCºCPr but not of the terminal alkynes HCºCH, PhCºCH, BuCºCH, or the alkynes containing one or two electron-withdrawing substituents PhCºCCO2Me and MeO2CCtriple bondCCO2Me. In the successful reactions, the formic acid is first decomposed to carbon dioxide and hydrogen, which then hydrogenates the alkynes in a slower reaction. In the unsuccessful reactions, the decomposition of formic acid is strongly retarded by the alkyne. In the case with the alkyne PhCºCH, it is shown that the alkyne reacts with protonated 1 to give first [Ru2(µ-CPh=CH2)(CO)4(µ-dppm)2][HCO2], which then isomerizes to give the catalytically inactive, stable complex [Ru2(µ-CH=CHPh)(CO)4(µ-dppm)2][HCO2]. This complex has been structurally characterized and both of the µ-styrenyl complexes are shown to be fluxional in solution.Key words: ruthenium, hydrogenation, catalysis, binuclear..

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12

Reinus, Brandon, and Sean Kerwin. "Preparation and Utility of N-Alkynyl Azoles in Synthesis." Molecules 24, no. 3 (January 24, 2019): 422. http://dx.doi.org/10.3390/molecules24030422.

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Heteroatom-substituted alkynes have attracted a significant amount of interest in the synthetic community due to the polarized nature of these alkynes and their utility in a wide range of reactions. One specific class of heteroatom-substituted alkynes combines this utility with the presence of an azole moiety. These N-alkynyl azoles have been known for nearly 50 years, but recently there has been a tremendous increase in the number of reports detailing the synthesis and utility of this class of compound. While much of the chemistry of N-alkynyl azoles mirrors that of the more extensively studied N-alkynyl amides (ynamides), there are notable exceptions. In addition, as azoles are extremely common in natural products and pharmaceuticals, these N-alkynyl azoles have high potential for accessing biologically important compounds. In this review, the literature reports of N-alkynyl azole synthesis, reactions, and uses have been assembled. Collectively, these reports demonstrate the growth in this area and the promise of exploiting N-alkynyl azoles in synthesis.

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13

Shaw, Ranjay, Amr Elagamy, Ismail Althagafi, and Ramendra Pratap. "Synthesis of alkynes from non-alkyne sources." Organic & Biomolecular Chemistry 18, no. 20 (2020): 3797–817. http://dx.doi.org/10.1039/d0ob00325e.

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14

Xu, Fen, Wen-Jing Zhu, Juan Wang, Qi Ma, and Li-Jing Shen. "Rhodium-catalyzed synthesis of substituted isoquinolones via a selective decarbonylation/alkyne insertion cascade of phthalimides." Organic & Biomolecular Chemistry 18, no. 40 (2020): 8219–23. http://dx.doi.org/10.1039/d0ob01793k.

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15

Parsons, Philip, Lewis Allen, Daniel Jones, Alex Padgham, James Pryke, Joseph McKenna, and Daniel O’Reilly. "Approaches to the Synthesis of Highly Substituted Aromatic and Fused Rings: Metal-Catalysed versus Thermal Cyclisation." Synthesis 50, no. 01 (November 27, 2017): 84–101. http://dx.doi.org/10.1055/s-0036-1590952.

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A domino reaction has been used for the construction of lactonamycin derivatives. This research led to a comparison study between palladium-mediated cascade cyclisations and thermal alkyne [2+2+2] cyclisations. A palladium-mediated cyclisation of alkenyl bromides with alkynes and furans has been shown to furnish highly substituted aromatic rings. Penta- and hexasubstituted aromatic rings have also been prepared by the thermolysis of suitably substituted alkynes under microwave conditions. Tetrasubstituted pyridines can also be prepared using nitriles instead of alkynes. This work will provide a new and interesting array of drug templates; mechanistic details are discussed for both reaction series.

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16

Silva, Pedro J. "The Reaction Mechanism of the Cu(I) Catalyzed Alkylation of Heterosubstituted Alkynes." Catalysts 13, no. 1 (December 23, 2022): 17. http://dx.doi.org/10.3390/catal13010017.

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Alkynes may be regioselectively alkylated to alkenes by organocopper reagents in a reaction known as “carbocupration”, where an alkylCu(I) binds to the alkyne and transfers its organic moiety to one of the alkyne carbon atoms. Alkynes hetero-substituted with third-row elements yield alkenes with a regiochemistry opposite to that obtained when using alkynes hetero-substituted with second-row elements. Early computational investigations of his reaction mechanism have identified the importance of the organocopper counter-cation (Li+) to the achievement of good reaction rates, but in the subsequent two decades no further progress has been reported regarding the exploration of the mechanism or the explanation of the experimental regiochemistry. In this work, density-functional theory is used to investigate the mechanism used and to describe a model that correctly explains both the reaction rates at sub-zero temperatures and the regiochemistry profiles obtained with each of the heteroalkynes. The rate-determining step is shown to vary depending on the heterosubstituent, and the alkyl transfer is consistently shown to occur, somewhat counter-intuitively, to the alkyne carbon that is complexed by Cu rather than to the “free” alkyne carbon atom, which instead interacts with the counter-cation that stabilizes the developing electronic charge distribution.

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17

Yoshida, Suguru, Tomoko Kuribara, Harumi Ito, Tomohiro Meguro, Yoshitake Nishiyama, Fumika Karaki, Yasutomo Hatakeyama, Yuka Koike, Isao Kii, and Takamitsu Hosoya. "A facile preparation of functional cycloalkynes via an azide-to-cycloalkyne switching approach." Chemical Communications 55, no. 24 (2019): 3556–59. http://dx.doi.org/10.1039/c9cc01113g.

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Terminal alkyne-selective click conjugation of diynes bearing strained and terminal alkyne moieties with functional azides has been achieved by transient protection of strained alkynes via complexation with copper to easily afford various functional cycloalkynes.

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18

Dastjerdi, Hossein Fasihi, Manijeh Nematpour, Elham Rezaee, Mehdi Jahani, and Sayyed Abbas Tabatabai. "A Novel Copper-Catalyzed Synthesis of N-Monosubstituted 2-Alkynimidamides from 1-Alkynes and Trichloroacetamidines." Letters in Organic Chemistry 17, no. 9 (September 17, 2020): 704–8. http://dx.doi.org/10.2174/1570178616666191023142821.

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A one-pot Cu-catalyzed synthesis of functionalized alkynyl imidamide by terminal alkynes, trichloroacetonitrile and aniline or benzyl amine is reported. The compounds were produced via coupling reaction of terminal alkynes with trichloroacetamidine. This method was performed under mild, ligand-free conditions and easy work-up method.

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19

Noonikara-Poyil, Anurag, Alvaro Muñoz-Castro, and H. V. Rasika Dias. "Terminal and Internal Alkyne Complexes and Azide-Alkyne Cycloaddition Chemistry of Copper(I) Supported by a Fluorinated Bis(pyrazolyl)borate." Molecules 27, no. 1 (December 21, 2021): 16. http://dx.doi.org/10.3390/molecules27010016.

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Copper plays an important role in alkyne coordination chemistry and transformations. This report describes the isolation and full characterization of a thermally stable, copper(I) acetylene complex using a highly fluorinated bis(pyrazolyl)borate ligand support. Details of the related copper(I) complex of HC≡CSiMe3 are also reported. They are three-coordinate copper complexes featuring η2-bound alkynes. Raman data show significant red-shifts in C≡C stretch of [H2B(3,5-(CF3)2Pz)2]Cu(HC≡CH) and [H2B(3,5-(CF3)2Pz)2]Cu(HC≡CSiMe3) relative to those of the corresponding alkynes. Computational analysis using DFT indicates that the Cu(I) alkyne interaction in these molecules is primarily of the electrostatic character. The π-backbonding is the larger component of the orbital contribution to the interaction. The dinuclear complexes such as Cu2(μ-[3,5-(CF3)2Pz])2(HC≡CH)2 display similar Cu-alkyne bonding features. The mononuclear [H2B(3,5-(CF3)2Pz)2]Cu(NCMe) complex catalyzes [3 + 2] cycloadditions between tolyl azide and a variety of alkynes including acetylene. It is comparatively less effective than the related trinuclear copper catalyst {μ-[3,5-(CF3)2Pz]Cu}3 involving bridging pyrazolates.

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20

Kantlehner, Willi, Ralf Kreß, Jochen Mezger, and Sebastian Ladendorf. "Orthoamide, LXI [1]. Ein neues leistungsfähiges Verfahren zur Synthese von Orthoamid- Derivaten von Alkincarbonsäuren / Orthoamide, LXI [1]. A New, Efficient Procedure for the Synthesis of Orthoamide Derivatives of Alkyne Carboxylic Acids." Zeitschrift für Naturforschung B 60, no. 2 (February 1, 2005): 227–30. http://dx.doi.org/10.1515/znb-2005-0217.

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21

Fukumoto, Yoshiya, Masato Daijo, and Naoto Chatani. "Rhenium(I)-catalyzed reaction of terminal alkynes with imines leading to allylamine derivatives." Pure and Applied Chemistry 86, no. 3 (March 20, 2014): 283–89. http://dx.doi.org/10.1515/pac-2014-5003.

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Abstract The rhenium-catalyzed reaction of terminal alkynes with imines gives N-alkylideneallylamine derivatives. A diphenylmethyl group as the substituent on the imine nitrogen gave the best result. Deuterium labeling experiments revealed that the regioselective addition of both the hydrogen and the N-alkylideneaminoalkyl group to the terminal alkynes also proceeded stereoselectively. While alkynes bearing primary and secondary alkyl-, vinyl-, and aryl groups were applicable to the catalytic reaction, tertiary alkyl- and silyl-substituted alkynes gave propargylamines. The C–C bond-forming step via the nucleophilic attack of the alkynyl β-carbon on the imine carbon leading to the formation of a vinylidene rhenium species appears to be involved in the catalytic cycle.

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22

Petko, Dina, Matthew Stratton, and William Tam. "Ruthenium-catalyzed Bis-Homo-Diels-Alder reaction: searching for commercially available catalysts and expanding the scope of reaction." Canadian Journal of Chemistry 96, no. 12 (December 2018): 1115–21. http://dx.doi.org/10.1139/cjc-2018-0117.

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Commercially available ruthenium catalyst, Cp*RuCl(COD), was found to be active in catalyzing Bis-Homo-Diels-Alder [2+2+2] cycloaddition reactions between 1,5-cyclooctadiene and various alkynes giving moderate to good yields (35%–92%). The presence of electron donating groups, especially hydroxyl groups, greatly enhanced the reactivity of the alkyne moiety in the cycloaddition. The reaction was also found to be successful even in the presence of bulky substituents on the alkynes.

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23

Basu, Basudeb, Kinkar Biswas, Samir Kundu, and Debasish Sengupta. "In Quest of “Stereoselective Switch” for On-Water Hydrothiolation of Terminal Alkynes Using Different Additives and Green Synthesis of Vicinal Dithioethers." Organic Chemistry International 2014 (February 13, 2014): 1–6. http://dx.doi.org/10.1155/2014/358932.

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On-water hydrothiolation reaction between terminal alkyne and thiol has been probed in the presence of various additives. Aromatic alkynes yield corresponding 1-alkenyl sulfides, whereas aliphatic alkynes undergo double-addition yielding vicinal disulfides in good to excellent yields. Formation of 1-alkenyl sulfides proceeds with a high degree of regioselectivity (via anti-Markovnikov addition), and switching the stereoselectivity between E/Z isomers has been noticeably realized in the presence of different additives/promoters.

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24

Yeager, Chris M., Peter J. Bottomley, Daniel J. Arp, and Michael R. Hyman. "Inactivation of Toluene 2-Monooxygenase in Burkholderia cepacia G4 by Alkynes." Applied and Environmental Microbiology 65, no. 2 (February 1, 1999): 632–39. http://dx.doi.org/10.1128/aem.65.2.632-639.1999.

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ABSTRACT High concentrations of acetylene (10 to 50% [vol/vol] gas phase) were required to inhibit the growth of Burkholderia cepaciaG4 on toluene, while 1% (vol/vol) (gas phase) propyne or 1-butyne completely inhibited growth. Low concentrations of longer-chain alkynes (C5 to C10) were also effective inhibitors of toluene-dependent growth, and 2- and 3-alkynes were more potent inhibitors than their 1-alkyne counterparts. Exposure of toluene-grownB. cepacia G4 to alkynes resulted in the irreversible loss of toluene- and o-cresol-dependent O2 uptake activities, while acetate- and 3-methylcatechol-dependent O2 uptake activities were unaffected. Toluene-dependent O2 uptake decreased upon the addition of 1-butyne in a concentration- and time-dependent manner. The loss of activity followed first-order kinetics, with apparent rate constants ranging from 0.25 min−1 to 2.45 min−1. Increasing concentrations of toluene afforded protection from the inhibitory effects of 1-butyne. Furthermore, oxygen, supplied as H2O2, was required for inhibition by 1-butyne. These results suggest that alkynes are specific, mechanism-based inactivators of toluene 2-monooxygenase inB. cepacia G4, although the simplest alkyne, acetylene, was relatively ineffective compared to longer alkynes. Alkene analogs of acetylene and propyne—ethylene and propylene—were not inactivators of toluene 2-monooxygenase activity in B. cepacia G4 but were oxidized to their respective epoxides, with apparentKs and V max values of 39.7 μM and 112.3 nmol min−1 mg of protein−1 for ethylene and 32.3 μM and 89.2 nmol min−1 mg of protein−1 for propylene.

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25

Schörgenhumer, J., and M. Waser. "Transition metal-free coupling of terminal alkynes and hypervalent iodine-based alkyne-transfer reagents to access unsymmetrical 1,3-diynes." Organic & Biomolecular Chemistry 16, no. 41 (2018): 7561–63. http://dx.doi.org/10.1039/c8ob02375a.

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26

Gobbo, Pierangelo, Tommaso Romagnoli, Stephanie M. Barbon, Jacquelyn T. Price, Jennifer Keir, Joe B. Gilroy, and Mark S. Workentin. "Expanding the scope of strained-alkyne chemistry: a protection–deprotection strategy via the formation of a dicobalt–hexacarbonyl complex." Chemical Communications 51, no. 30 (2015): 6647–50. http://dx.doi.org/10.1039/c5cc01522g.

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A protection–deprotection strategy for strained alkynes is reported. A strained alkyne can be protected with dicobalt–octacarbonyl and we demonstrate for the first time that the a strained alkyne can be re-formed and isolated under mild conditions for further bioorthogonal reactivity.

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27

Smith, Courtney A., Stephen E. Motika, Lukasz Wojtas, and Xiaodong Shi. "Accessing alternative reaction pathways of the intermolecular condensation between homo-propargyl alcohols and terminal alkynes through divergent gold catalysis." Chemical Communications 53, no. 15 (2017): 2315–18. http://dx.doi.org/10.1039/c6cc09794d.

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28

Mukherjee, Nirmalya, Subhajit Pal, Amit Saha, and Brindaban C. Ranu. "Silver-catalyzed carbon–selenium cross-coupling using N-(phenylseleno)phthalimide: an alternate approach to the synthesis of organoselenides." Canadian Journal of Chemistry 95, no. 1 (January 2017): 51–56. http://dx.doi.org/10.1139/cjc-2016-0427.

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Silver(I) catalyzed phenylselenylation of terminal alkynes and organoboronic acids has been demonstrated using N-(phenylseleno)phthalimide as an electrophilic SePh donor. A wide variety of terminal alkynes and organoboronic acids are selenylated efficiently to produce the corresponding alkynyl and diaryl selenides, respectively, in good yields. Silver(I) acts as a Lewis acid in this process.

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29

Rifhat Bibi, Rifhat Bibi, Muhammad Yaseen Muhammad Yaseen, Haseen Ahmad Haseen Ahmad, Ismat Ullah Khan Ismat Ullah Khan, Shaista Parveen Shaista Parveen, and Abbas Hassan Abbas Hassan. "Palladium Catalyzed Synthesis of Phenylquinoxaline-Alkyne Derivatives via Sonogashira Cross Coupling Reaction." Journal of the chemical society of pakistan 43, no. 1 (2021): 95. http://dx.doi.org/10.52568/000550.

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Transition metals mediated cross coupling methodologies provide an extremely powerful versatile pathway in organic syntheses undoubtedly, a facile route for syntheses and derivatization of biologically important heterocycles from easily available precursors. Sonogashira coupling reaction, a leading method to Csp-Csp2 bond formation is one of the most important and rapid pathways to couple aryl/vinyl halides with terminal alkynes. Current research study deals with the synthesis of alkyne substituted quinoxaline derivatives. The quinoxalines class of aromatic heterocycles exhibits a wide variety of important biological potencies. Palladium catalyzed cross coupling process provided an effective synthetic practice for the synthesis of alkyne derivatives of quinoxaline. Vareity of terminal alkynes were coupled with 2-(4-bromophenyl)quinoxaline under optimized conditions for Sonogashira reaction, affording alkyne substituted quinoxaline derivatives in high yields. The optimized reaction conditions for coupling of range of terminal alkyne with quinoxaline basic core render this process significant for designing of medicinally interesting precursors.

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30

Rifhat Bibi, Rifhat Bibi, Muhammad Yaseen Muhammad Yaseen, Haseen Ahmad Haseen Ahmad, Ismat Ullah Khan Ismat Ullah Khan, Shaista Parveen Shaista Parveen, and Abbas Hassan Abbas Hassan. "Palladium Catalyzed Synthesis of Phenylquinoxaline-Alkyne Derivatives via Sonogashira Cross Coupling Reaction." Journal of the chemical society of pakistan 43, no. 1 (2021): 95. http://dx.doi.org/10.52568/000550/jcsp/43.01.2021.

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Transition metals mediated cross coupling methodologies provide an extremely powerful versatile pathway in organic syntheses undoubtedly, a facile route for syntheses and derivatization of biologically important heterocycles from easily available precursors. Sonogashira coupling reaction, a leading method to Csp-Csp2 bond formation is one of the most important and rapid pathways to couple aryl/vinyl halides with terminal alkynes. Current research study deals with the synthesis of alkyne substituted quinoxaline derivatives. The quinoxalines class of aromatic heterocycles exhibits a wide variety of important biological potencies. Palladium catalyzed cross coupling process provided an effective synthetic practice for the synthesis of alkyne derivatives of quinoxaline. Vareity of terminal alkynes were coupled with 2-(4-bromophenyl)quinoxaline under optimized conditions for Sonogashira reaction, affording alkyne substituted quinoxaline derivatives in high yields. The optimized reaction conditions for coupling of range of terminal alkyne with quinoxaline basic core render this process significant for designing of medicinally interesting precursors.

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31

Rifhat Bibi, Rifhat Bibi, Muhammad Yaseen Muhammad Yaseen, Haseen Ahmad Haseen Ahmad, Ismat Ullah Khan Ismat Ullah Khan, Shaista Parveen Shaista Parveen, and Abbas Hassan Abbas Hassan. "Palladium Catalyzed Synthesis of Phenylquinoxaline-Alkyne Derivatives via Sonogashira Cross Coupling Reaction." Journal of the chemical society of pakistan 43, no. 1 (2021): 95. http://dx.doi.org/10.52568/000009.

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Transition metals mediated cross coupling methodologies provide an extremely powerful versatile pathway in organic syntheses undoubtedly, a facile route for syntheses and derivatization of biologically important heterocycles from easily available precursors. Sonogashira coupling reaction, a leading method to Csp-Csp2 bond formation is one of the most important and rapid pathways to couple aryl/vinyl halides with terminal alkynes. Current research study deals with the synthesis of alkyne substituted quinoxaline derivatives. The quinoxalines class of aromatic heterocycles exhibits a wide variety of important biological potencies. Palladium catalyzed cross coupling process provided an effective synthetic practice for the synthesis of alkyne derivatives of quinoxaline. Vareity of terminal alkynes were coupled with 2-(4-bromophenyl)quinoxaline under optimized conditions for Sonogashira reaction, affording alkyne substituted quinoxaline derivatives in high yields. The optimized reaction conditions for coupling of range of terminal alkyne with quinoxaline basic core render this process significant for designing of medicinally interesting precursors.

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32

Zhang, Qing-Wei, Xu-Teng Liu, and Yue Wu. "Nickel-Catalyzed Asymmetric Synthesis of P-Stereogenic Vinyl Phosphines." Synlett 33, no. 04 (November 12, 2021): 301–6. http://dx.doi.org/10.1055/a-1695-4979.

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AbstractAddition reaction to alkynes is an efficient strategy for constructing valuable alkenyl compounds. However, the elusive regioselectivity has been a persistent challenge. In the context of hydrophosphination reaction which could afford valuable P-stereogenic phosphines, the control of enantioselectivity as well as regioselectivity were especially tricky. Here, we highlighted our recent work on the nickel-catalyzed regio- and enantioselective hydrophosphination of unactivated alkynes with in situ generated secondary phosphines.1 Introduction2 Hydrophosphination of Alkynes3 Derivatization Reactions4 Mechanism Research5 Summary and Outlook

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33

Yang, Jingyue, Tung T. Hoang, and Gregory B. Dudley. "Alkynogenic fragmentation." Organic Chemistry Frontiers 6, no. 15 (2019): 2560–69. http://dx.doi.org/10.1039/c9qo00266a.

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34

Hosseini, Abolfazl, Afsaneh Pilevar, Eimear Hogan, Boris Mogwitz, Anne S. Schulze, and Peter R. Schreiner. "Calcium carbide catalytically activated with tetra-n-butyl ammonium fluoride for Sonogashira cross coupling reactions." Organic & Biomolecular Chemistry 15, no. 32 (2017): 6800–6807. http://dx.doi.org/10.1039/c7ob01334e.

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35

Wang, Dong, Qingsen Guo, Hong Gao, Zhou Yang, Yan Xing, Hui Cao, Wanli He, Huihui Wang, Jianming Gu, and Huiying Hu. "The application of double click to synthesize a third-order nonlinear polymer containing donor–acceptor chromophores." Polymer Chemistry 7, no. 22 (2016): 3714–21. http://dx.doi.org/10.1039/c6py00106h.

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36

Das, Uttam Kumar, Rajesh K. Jena, and Manish Bhattacharjee. "Synthesis, structure and catalytic properties of [Ru(dppp)2(CH3CN)Cl][BPh4] and isolation of catalytically active [Ru(dppp)2Cl][BPh4]: ruthenium catalysed alkyne homocoupling and tandem alkyne–azide cycloaddition." RSC Adv. 4, no. 42 (2014): 21964–70. http://dx.doi.org/10.1039/c4ra01411a.

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37

Matsuda, Takanori, and Takeshi Matsumoto. "Rhodium(i)-catalysed intermolecular alkyne insertion into (2-pyridylmethylene)cyclobutenes." Organic & Biomolecular Chemistry 14, no. 22 (2016): 5023–27. http://dx.doi.org/10.1039/c6ob00734a.

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Multiply substituted benzenes were prepared by rhodium(i)-catalysed reaction of (2-pyridylmethylene)cyclobutenes with alkynes through an intermolecular alkyne insertion into the carbon–carbon bond of cyclobutenes.

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38

Duan, Chang-Lin, Xing-Yu Liu, Yun-Xuan Tan, Rui Ding, Shiping Yang, Ping Tian, and Guo-Qiang Lin. "Acetic Acid-Promoted Rhodium(III)-Catalyzed Hydroarylation of Terminal Alkynes." Synlett 30, no. 08 (March 26, 2019): 932–38. http://dx.doi.org/10.1055/s-0037-1611780.

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Rhodium(III)-catalyzed hydroarylation of terminal alkynes has not previously been achieved because of the inevitable oligomerization and other side reactions. Here, we report a novel Cp*Rh(III)-catalyzed hydroarylation of terminal alkynes in acetic acid as solvent to facilitate the C–H bond activation and subsequent transformations. This reaction proceeds under mild conditions, providing an effective approach to the synthesis of alkenylated heterocycles in high to excellent yields (31–99%) with a broad substrate scope (37 examples) and good functional-group compatibility. In this transformation, the loading of the alkyne can be reduced to 1.2 equivalents, which indicates the significant role of HOAc in lowering the reaction temperature and suppressing the oligomerization of the terminal alkyne. Preliminary mechanistic studies are also presented.

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39

Tse, Sunny Kai San, Herman Ho-Yung Sung, Ian Duncan Williams, and Guochen Jia. "Vinylidene, allenylidene, cyclic oxycarbene, and η2-alkyne complexes from reactions of (η5-C5Me5)OsCl(PPh3)2 with alkynes and alkynols." Canadian Journal of Chemistry 99, no. 2 (February 2021): 268–76. http://dx.doi.org/10.1139/cjc-2020-0320.

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Reactions of Cp*OsCl(PPh3)2 (Cp* = pentamethylcyclopentadienyl) with alkynes and alkynols are described. Treatment of Cp*OsCl(PPh3)2 with phenylacetylene and trimethylsilylacetylene gave the vinylidene complexes Cp*OsCl(=C=CHPh)(PPh3) and Cp*OsCl(=C=CH2)(PPh3), respectively. Treatment of Cp*OsCl(PPh3)2 with the internal alkyne dimethyl acetylenedicarboxylate produced the η2-alkyne complex Cp*OsCl(η2-MeO2C≡CCO2Me)(PPh3). Treatment of Cp*OsCl(PPh3)2 with the propargylic alcohol HC≡CC(OH)Ph2 gave the osmium allenylidene complex Cp*OsCl(=C = C=CPh2)(PPh3). The outcomes of the reactions of Cp*OsCl(PPh3)2 with ω-alkynols HC≡C(CH2)nOH are dependent on the length of the -(CH2)n- linker. The reaction with 3-butyn-1-ol produced the cyclic oxycarbene complex Cp*OsCl{=C(CH2)3O}(PPh3) exclusively. The reactions with 4-pentyn-1-ol produced a mixture of the hydroxyalkyl vinylidene complex Cp*OsCl{=C=CH(CH2)3OH}(PPh3) and the cyclic oxycarbene complex Cp*OsCl{=C(CH2)4O}(PPh3) in about 10:1 molar ratio. The reaction with 5-hexyn-1-ol gave exclusively the hydroxyalkyl vinylidene complex Cp*OsCl{=C=CH(CH2)4OH}(PPh3).

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40

Eaves, Samantha G., Dmitry S. Yufit, Brian W. Skelton, Jason M. Lynam, and Paul J. Low. "Reactions of alkynes with cis-RuCl2(dppm)2: exploring the interplay of vinylidene, alkynyl and η3-butenynyl complexes." Dalton Transactions 44, no. 48 (2015): 21016–24. http://dx.doi.org/10.1039/c5dt03844h.

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41

Vohradská, Nikoleta, Esther M. Sánchez-Carnerero, Tomáš Pastierik, Ctibor Mazal, and Petr Klán. "Controlled photorelease of alkynoic acids and their decarboxylative deprotection for copper-catalyzed azide/alkyne cycloaddition." Chemical Communications 54, no. 44 (2018): 5558–61. http://dx.doi.org/10.1039/c8cc03341b.

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A controlled photorelease of alkynoic acids from a photoremovable protecting group (PPG) facilitates their subsequent decarboxylation to deliver terminal alkynes for a Cu^I-catalyzed azide/alkyne cycloaddition.

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42

Arora, Inderpreet, Sandeep K. Sharma, and Arun K. Shaw. "Aglycone mimics for tuning of glycosidase inhibition: design, synthesis and biological evaluation of bicyclic pyrrolidotriazole iminosugars." RSC Advances 6, no. 16 (2016): 13014–26. http://dx.doi.org/10.1039/c5ra26005a.

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Various fuco-configured bicyclic pyrrolidotriazole aglycone mimics were synthesised using copper-catalysed coupling of allyl bromides with terminal alkynes and Sonogashira–Hagihara reaction followed by intramolecular azide-alkyne ‘click’ reaction.

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43

Wan, Jie-Ping, Yunfang Lin, Kaikai Hu, and Yunyun Liu. "Secondary amine-initiated three-component synthesis of 3,4-dihydropyrimidinones and thiones involving alkynes, aldehydes and thiourea/urea." Beilstein Journal of Organic Chemistry 10 (January 29, 2014): 287–92. http://dx.doi.org/10.3762/bjoc.10.25.

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The three-component reactions of aldehydes, electron deficient alkynes and ureas/thioureas have been smoothly performed to yield a class of unprecedented 3,4-dihydropyrimidinones and thiones (DHPMs). The reactions are initiated by the key transformation of an enamine-type activation involving the addition of a secondary amine to an alkyne, which enables the subsequent incorporation of aldehydes and ureas/thioureas. This protocol tolerates a broad range of aryl- or alkylaldehydes, N-substituted and unsubstituted ureas/thioureas and alkynes to yield the corresponding DHPMs with specific regioselectivity.

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44

Zhu, Shizheng, Guifang Jin, and Huiling Jiang. "Reactions of β-alkoxyvinyl trifluoromethyl ketones with terminal alkynes Reagent-controlled regioselectivity addition reactions." Canadian Journal of Chemistry 83, no. 12 (December 1, 2005): 2127–31. http://dx.doi.org/10.1139/v05-247.

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Reactions of β-alkoxyvinyl trifluoromethyl ketones ROCH=CHCOCF3 (1, R = Et, Me2CHCH2), and their cyclic analogues 4-trifluoroacetyl-2,3-dihydrofuran (2a) and 5-trifluoroacetyl-3,4-dihydro-2H-pyran (2b), with terminal alkynes R-C≡CH (3, R = Ph, PhCH2, HOCH2, C5H11) mainly gave the 1,2-addition products (carbonyl alkynylation) in the presence of n-BuLi. However, promoted by ZnCl2Et3N, the reaction of 1 or 2 with equivalent alkyne predominately provided 1,4-addition products.Key words: β-alkoxyvinyl trifluoromethyl ketones, alkynes, 1,2-addition, 1,4-addition, catalysts.

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45

Selander, Nicklas, Stalin Pathipati, and Angela van der Werf. "Indium(III)-Catalyzed Transformations of Alkynes: Recent Advances in Carbo- and Heterocyclization Reactions." Synthesis 49, no. 22 (August 30, 2017): 4931–41. http://dx.doi.org/10.1055/s-0036-1588555.

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The use of a well-chosen catalyst is instrumental for the development of more efficient, economical and environmentally friendly reactions. In recent decades, indium-based catalysts have proven to be competitive and useful alternatives to transition-metal catalysts such as silver and gold. In this short review, we present some of the recent advances in indium(III)-catalyzed transformations of alkynes, with a focus on cyclization reactions.1 Introduction2 Terminal Alkynes as Nucleophiles3 Nucleophilic Additions to Alkynes4 Carbo- and Heterocyclization Reactions4.1 Carbocyclization4.2 Oxygen-Based Heterocycles4.3 Nitrogen-Based Heterocycles4.4 Sulfur-Based Heterocycles5 Conclusion

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46

Mamatha, M., Sathiyaraj Chinnasamy, and Ashwini Murugan. "The Development of Terminal Alkynes in Water Using DEMATEL Method." Journal on Materials and its Characterization 1, no. 1 (September 1, 2022): 17–27. http://dx.doi.org/10.46632/jmc/1/1/3.

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In organic chemistry, an alkyne is an unsaturated; Hydrocarbon is at least one carbon-three carbon has a bond. All three alkynes are unsaturated have a bond containing hydrocarbons, Alkynes have the general formula CnH2n-2 and three the bond is called 'acetylenic bond'. is called The functional group in the alkyne is a Carbon-carbon is three binding. Aromatics are π bonds odd number of electron in the system Planar with pairs, fully coupled and are cyclic structures. In which test to conclude from analysis and Evaluation Laboratory (DEMATEL) of complex system components a cause-and-effect chain is considered correct One of the best to identify. It values relationships Interdependence between factors and identification through visual structural modeling Important to see. Alternative: Propene (C3H6), Butene (C4H8), Pentene (C5H10), Hexene (C6H12), Heptene (C7H14). Evaluation Preference: Propene (C3H6), Butene (C4H8), Pentene (C5H10), Hexene (C6H12), Heptene (C7H14). The result it is seen that Hexene (C6H12) is got the first rank where as is the Pentene (C5H10) is having the lowest rank. The value of the dataset for Alkynes in Test and evaluate decision making the lab shows that it results in Hexene (C6H12) and top ranking.

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47

He, Haiqing, and Hong-Bo Qin. "ZnBr2-catalyzed directC-glycosylation of glycosyl acetates with terminal alkynes." Organic Chemistry Frontiers 5, no. 12 (2018): 1962–66. http://dx.doi.org/10.1039/c8qo00380g.

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48

Evoniuk, Christopher J., Michelle Ly, and Igor V. Alabugin. "Coupling cyclizations with fragmentations for the preparation of heteroaromatics: quinolines from o-alkenyl arylisocyanides and boronic acids." Chemical Communications 51, no. 64 (2015): 12831–34. http://dx.doi.org/10.1039/c5cc04391c.

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Stereoelectronic restrictions on homoallylic ring expansion in alkyne cascades can be overcome by using alkenes as synthetic equivalents of alkynes in reaction cascades that are terminated by C–C bond fragmentation.

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49

Chronopoulos, Demetrios D., Miroslav Medved’, Piotr Błoński, Zdeněk Nováček, Petr Jakubec, Ondřej Tomanec, Aristides Bakandritsos, Veronika Novotná, Radek Zbořil, and Michal Otyepka. "Alkynylation of graphene via the Sonogashira C–C cross-coupling reaction on fluorographene." Chemical Communications 55, no. 8 (2019): 1088–91. http://dx.doi.org/10.1039/c8cc08492k.

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50

Chatterjee, Rana, Sougata Santra, Grigory Zyryanov, and Adinath Majee. "Vinylation of Carbonyl Oxygen in 4-Hydroxycoumarin: Synthesis of Heteroarylated Vinyl Ethers." Synthesis 51, no. 11 (March 7, 2019): 2371–78. http://dx.doi.org/10.1055/s-0037-1610696.

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The unique nucleophilic character of the carbonyl oxygen of 4-hydroxy coumarin has been observed by the BF3·OEt2 catalyzed reaction of 4-hydroxycoumarin and alkynes. The reactions of 4-hydroxycoumarin and substituted 4-hydroxycoumarin with various terminal alkynes have been studied. In case of internal alkyne (prop-1-yn-1-ylbenzene), the reaction with 4-hydroxycoumarin led to the corresponding product with an E/Z ratio of 3:1. This protocol is operationally very simple and has much potential for the synthesis of heteroarylated vinyl ethers from basic chemicals.

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