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Journal articles on the topic 'Alkyne group'

Author: Grafiati

Published: 24 April 2022

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1

Potapov, Vladimir A., Maxim V. Musalov, Evgeny O. Kurkutov, Vladimir A. Yakimov, Alfiya G. Khabibulina, Maria V. Musalova, Svetlana V. Amosova, Tatyana N. Borodina, and Alexander I. Albanov. "Remarkable Alkene-to-Alkene and Alkene-to-Alkyne Transfer Reactions of Selenium Dibromide and PhSeBr. Stereoselective Addition of Selenium Dihalides to Cycloalkenes." Molecules 25, no. 1 (January 3, 2020): 194. http://dx.doi.org/10.3390/molecules25010194.

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The original goal of this research was to study stereochemistry of selenium dihalides addition to cycloalkenes and properties of obtained products. Remarkable alkene-to-alkene and alkene-to-alkyne transfer reactions of selenium dibromide and PhSeBr were discovered during this research. The adducts of selenium dibromide with alkenes or cycloalkenes easily exchange SeBr2 with other unsaturated compounds, including acetylenes, at room temperature, in acetonitrile. Similar alkene-to-alkene and alkene-to-alkyne transfer reactions of the PhSeBr adducts with alkenes or cycloalkenes take place. The supposed reaction pathway includes the selenium group transfer from seleniranium species to alkenes or alkynes. It was found that the efficient SeBr2 and PhSeBr transfer reagents are Se(CH2CH2Br)2 and PhSeCH2CH2Br, which liberate ethylene, leading to a shift in equilibrium. The regioselective and stereoselective synthesis of bis(E-2-bromovinyl) selenides and unsymmetrical E-2-bromovinyl selenides was developed based on the SeBr2 and PhSeBr transfer reactions which proceeded with higher selectivity compared to analogous addition reactions of SeBr2 and PhSeBr to alkynes under the same conditions.

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2

Alexander, S. R., G. M. Williams, M. A. Brimble, and A. J. Fairbanks. "A double-click approach to the protecting group free synthesis of glycoconjugates." Organic & Biomolecular Chemistry 16, no. 8 (2018): 1258–62. http://dx.doi.org/10.1039/c8ob00072g.

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3

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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4

Wang, Li-Sheng, and Martin Cowie. "Alkyne transformations at RhMn centres. Facile conversion between parallel and perpendicular alkyne binding modes and conversions to vinyl groups." Canadian Journal of Chemistry 73, no. 7 (July 1, 1995): 1058–71. http://dx.doi.org/10.1139/v95-131.

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The heterobinuclear complex [RhMn(CO)4(dppm)2] (1) (dppm = Ph2PCH2PPh2) reacts with alkynes (RC≡CR; R = CO2Me (DMAD), CF3 (HFB)) to yield the alkyne-bridged products [RhMn(CO)4(μ-RC2R)(dppm)2] (3a, 3b), in which the alkyne binds parallel to the metals. These species lose one carbonyl to yield two isomers in which the bridging alkyne group is either parallel or perpendicular to the Rh–Mn vector (4 or 5). Unusually facile interconversion between these two alkyne binding modes occurs. Protonation of the different alkyne-bridged species appears to occur at the metals with subsequent transfer to the alkyne ligand, yielding a series of vinyl complexes. These vinyl complexes are also obtained from the reaction of the hydride-bridged complex [RhMn(CO)4(μ-H)(dppm)2][BF4] (2) with alkynes. A related vinyl species [RhMn((CH3)C=CH2)(CO)4(dppm)2][BF4] (9a) is obtained in the reaction of 2 with allene. Also obtained in the allene reaction is the isomeric η1-allyl complex [RhMn(η1-CH2C(H)=CH2)(CO)4(dppm)2][BF4] (9b), which converts to 9a upon refluxing. The methyl analogues [RhMnCH3(CO)4(dppm)2][X] (X = SO3CF3, I) have been characterized and their structural formulations offer support for those of the vinyl species. Keywords: heterobinuclear, alkyne complexes, vinyl complexes.

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5

Benhamou, Laure, Daniel W. Walker, Dejan-Krešimir Bučar, Abil E. Aliev, and Tom D. Sheppard. "Synthesis of substituted benzooxaborinin-1-ols via palladium-catalysed cyclisation of alkenyl- and alkynyl-boronic acids." Organic & Biomolecular Chemistry 14, no. 34 (2016): 8039–43. http://dx.doi.org/10.1039/c6ob01419d.

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6

Ouyang, Xuan-Hui, Yang Li, Ren-Jie Song, Ming Hu, Shenglian Luo, and Jin-Heng Li. "Intermolecular dialkylation of alkenes with two distinct C(sp3)─H bonds enabled by synergistic photoredox catalysis and iron catalysis." Science Advances 5, no. 3 (March 2019): eaav9839. http://dx.doi.org/10.1126/sciadv.aav9839.

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The functionalization of unactivated C(sp3)─H bonds represents one of the most powerful and most atom-economical tools for the formation of new carbon-based chemical bonds in synthesis. Although cross-dehydrogenative coupling reactions of two distinct C─H bonds for the formation of carbon-carbon bonds have been well investigated, controlled functionalizations of two or more different C(sp3)─H bonds across a functional group or a molecule (e.g., an alkene or alkyne) in a single reaction remain challenging. Here, we present a three-component dialkylation of alkenes with common alkanes and 1,3-dicarbonyl compounds via synergistic photoredox catalysis and iron catalysis for the synthesis of two functionalized 1,3-dicarbonyl compounds. Mechanistic studies suggest that the photoredox catalysis serves as a promotion system to allow the dialkylation to proceed under mild conditions by reducing the oxidation and reduction potentials of the iron intermediates and the reaction partners.

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7

Vasilevsky, Sergei F., Maria P. Davydova, Victor I. Mamatyuk, Nikolay Tsvetkov, Audrey Hughes, Denis S. Baranov, and Igor V. Alabugin. "Full Cleavage of C≡C Bond in Electron-Deficient Alkynes via Reaction with Ethylenediamine." Australian Journal of Chemistry 70, no. 4 (2017): 421. http://dx.doi.org/10.1071/ch17026.

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Reaction of 1,2-diaminioethane (ethylenediamine) with electron-deficient alkynes leads to full scission of the C≡C bond even in the absence of a keto group directly attached to the alkyne. This process involves oxidation of one of the alkyne carbons into C2 of a 2-R-4,5-dihydroimidazole with the concomitant reduction of the other carbon to a methyl group. The sequence of Sonogashira coupling with the ethylenediamine-mediated fragmentation described in this work can be used for selective formal substitution of halogen in aryl halides by a methyl group or a 4,5-dihydroimidazol-2-yl moiety.

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8

Scheiner, Steve. "Versatility of the Cyano Group in Intermolecular Interactions." Molecules 25, no. 19 (September 30, 2020): 4495. http://dx.doi.org/10.3390/molecules25194495.

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Several cyano groups are added to an alkane, alkene, and alkyne group so as to construct a Lewis acid molecule with a positive region of electrostatic potential in the area adjoining these substituents. Although each individual cyano group produces only a weak π-hole, when two or more such groups are properly situated, they can pool their π-holes into one much more intense positive region that is located midway between them. A NH3 base is attracted to this site, where it forms a strong noncovalent bond to the Lewis acid, amounting to as much as 13.6 kcal/mol. The precise nature of the bonding varies a bit from one complex to the next but typically contains a tetrel bond to the C atoms of the cyano groups or the C atoms of the linkage connecting the C≡N substituents. The placement of the cyano groups on a cyclic system like cyclopropane or cyclobutane has a mild weakening effect upon the binding. Although F is comparable to C≡N in terms of electron-withdrawing power, the replacement of cyano by F substituents substantially weakens the binding with NH3.

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9

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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10

Hadlington, Terrance J., Markus Hermann, Gernot Frenking, and Cameron Jones. "Two-coordinate group 14 element(ii) hydrides as reagents for the facile, and sometimes reversible, hydrogermylation/hydrostannylation of unactivated alkenes and alkynes." Chemical Science 6, no. 12 (2015): 7249–57. http://dx.doi.org/10.1039/c5sc03376d.

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The ambient temperature hydrometallations of a variety of unactivated alkene and alkyne substrates using two-coordinate hydrido-tetrylenes, :E(H)(L^†) (E = Ge or Sn; L^† = extremely bulky amide), are reported.

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11

Dockendorff, Chris, Eric Greve, and Jacob Porter. "DFT-Assisted Design and Evaluation of Bifunctional Amine/Pyridine-Oxazoline Metal Catalysts for Additions of Ketones to Unactivated Alkenes and Alkynes." Synthesis 51, no. 02 (October 2, 2018): 450–62. http://dx.doi.org/10.1055/s-0037-1610285.

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Bifunctional catalyst systems for the direct addition of ketones to unactivated alkenes/alkynes were designed and modeled by density functional theory (DFT). The designed catalysts possess bidentate ligands suitable for binding of pi-acidic group 10 metals capable of activating alkenes/alkynes, and a tethered organocatalyst amine to activate the ketone via formation of a nucleophilic enamine intermediate. The structures of the designed catalysts before and after C–C bond formation were optimized using DFT, and reaction steps involving group 10 metals were predicted to be significantly exergonic. A novel oxazoline precatalyst with a tethered amine separated by a meta-substituted benzene spacer was synthesized via a 10-step sequence that includes a key regioselective epoxide ring-opening step. It was combined with group 10 metal salts, including cationic Pd(II) and Pt(II), and screened for the direct addition of ketones to several alkenes and an internal alkyne. 1H NMR studies suggest that catalyst-catalyst interactions with this system via amine–metal coordination may preclude the desired addition reactions. The catalyst design approach disclosed here, and the promising calculations obtained with square planar group 10 metals, light a path for the discovery of novel bifunctional catalysts for C–C bond formation.

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12

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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13

Shen, Kun, and Qiu Wang. "Copper-catalyzed aminoalkynylation of alkenes with hypervalent iodine reagents." Chemical Science 8, no. 12 (2017): 8265–70. http://dx.doi.org/10.1039/c7sc03420b.

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A copper-catalyzed aminoalkynylation reaction of alkenes is developed for construction of diverse azaheterocycles and installation of an alkyne group in one step, presenting broad applications in synthesis, bioconjugation, and molecular imaging.

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14

Siddaraj, Ranjith, Raghu Ningegowda, Nanjunda Swamy Shivananju, and Babu Shubha Priya. "A mild and efficient method for the deprotection of trimethyl silyl alkynes using sodium ascorbate and copper sulphate." European Journal of Chemistry 9, no. 4 (December 31, 2018): 317–21. http://dx.doi.org/10.5155/eurjchem.9.4.317-321.1729.

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A competent and fast method for the deprotection of trimethyl silyl group was attained by using cheap, easily accessible, and nontoxic sodium ascorbate in combination with copper sulphate. The method labored was simple and effective for the cleavage of trimethyl silyl group from the protected trimethyl silyl alkynes to their corresponding alkyne derivatives. Wide functional group tolerance, shorter time period, simple procedure and high yields are the striking features of this protocol.

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15

Domena, Justin, Carlos Chong, Qiaxian Johnson, Bhanu Chauhan, and Yalan Xing. "Highly Efficient Recyclable Sol Gel Polymer Catalyzed One Pot Difunctionalization of Alkynes." Molecules 23, no. 8 (July 27, 2018): 1879. http://dx.doi.org/10.3390/molecules23081879.

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Amino-bridged gel polymer P1 was discovered to catalyze alkyne halo-functionalization in excellent yields, regioselectivity, functional group compatibility, and recyclability. We have observed that both aromatic and aliphatic alkynes can be converted to α,α-dihalogenated ketones in the presence of polymer P1 under metal-free conditions at room temperature within a short reaction time.

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16

Yang, Yuzhong, Liwei Zhou, Xiumei Yang, Xiai Luo, Guobo Deng, Yuan Yang, and Yun Liang. "Synthesis of Phenanthrenes via Palladium-Catalyzed Three-Component Domino Reaction of Aryl Iodides, Internal Alkynes, and o-Bromobenzoic Acids." Synthesis 52, no. 08 (October 29, 2019): 1223–30. http://dx.doi.org/10.1055/s-0039-1690737.

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A new palladium-catalyzed domino alkyne insertion/C–H activation/decarboxylation sequence has been developed, which provides an efficient approach for synthesizing a variety of functionalized phenanthrenes in moderate to good yields. The method shows broad substrate scope and good functional group tolerance by employing readily available materials, including aryl iodides, internal alkynes, and o-bromobenzoic acids, as three-component coupling partners.

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17

Kore, Nitin, and Pavel Pazdera. "New Stable Cu(I) Catalyst Supported on Weakly Acidic Polyacrylate Resin for “Click” Chemistry: Synthesis of 1,2,3-Triazole and Novel Synthesis of 1,2,3-Triazol-5-amine." Current Organic Synthesis 15, no. 4 (June 12, 2018): 552–65. http://dx.doi.org/10.2174/1570179415666180110152642.

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Aim and Objective: The aim of our work is to demonstrate catalytic application of our previously reported simple Cu(I) ion supported on weakly acidic polyacrylate resin for Azide-Alkyne cycloaddition (CuAAC), Azide-Nitrile cycloaddition and in synthesis of 1-azido-4-methoxybenzene. Material and Method: To investigate the catalytic ability of title Cu(I) catalyst we performed the reaction of different aryl azide with a broader spectrum of different terminal alkyne and nitrile compounds. Results: The title supported Cu(I) catalyzes cycloaddition reactions of aryl azide with aliphatic, aromatic, and heterocyclic terminal alkynes and corresponding 1,4-disubstituted 1,2,3-triazoles were obtained almost in the quantitative yields. The cycloaddition reactions of aryl azide with nitriles consisting α-hydrogen on carbon attached to cyano group under catalytic action of the title supported Cu(I) ended up with the formation of 1,4- disubstituted 1,2,3-triazol-5-amines in quantitative yields. The title catalyst found to be active for nucleophilic substitution of aide group (-N3) to 4-Iodoanisole. Conclusion: It was found that both studied Azide-Alkyne cycloaddition and Azide-Nitrile cycloaddition syntheses are regioselective and quantitative in yield. The title catalyst used is economical, easily preparable, separable, and recyclable. Therefore, the studied syntheses may be regarded as environmentally clean and green processes.

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18

Fadel, Salah, Youssef Hajbi, Mostafa Khouili, Said Lazar, Franck Suzenet, and Gérald Guillaumet. "Synthesis of 3,4-dihydro-1,8-naphthyridin-2(1H)-ones via microwave-activated inverse electron-demand Diels–Alder reactions." Beilstein Journal of Organic Chemistry 10 (January 28, 2014): 282–86. http://dx.doi.org/10.3762/bjoc.10.24.

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Substituted 3,4-dihydro-1,8-naphthyridin-2(1H)-ones have been synthesized with the inverse electron-demand Diels–Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels–Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H)-ones by an efficient synthetic route.

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19

Ali, Tammar H., Thorsten Heidelberg, Rusnah S. D. Hussen, and Hairul A. Tajuddin. "Unexpected Reactions of Terminal Alkynes in Targeted “Click Chemistry’’ Coppercatalyzed Azide-alkyne Cycloadditions." Current Organic Synthesis 16, no. 8 (January 20, 2020): 1143–48. http://dx.doi.org/10.2174/1570179416666191105152714.

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Background: High efficiency in terms of reaction yield and purity has led to the extensive utilization of copper-catalyzed azide-alkyne cycloaddition (CuAAC) in various fields of chemistry. Its compatibility with low molecular weight alcohols promotes the application in surfactant synthesis to tackle the miscibility constraints of the reactants. Objective: For the tuning of surfactant properties, double click coupling of the antipode precursors was attempted. Failure of the CuAAC to provide the targeted product in combination with unexpected reaction outputs led to an investigation of the side reaction. Methods: The CuAAC-based coupling of sugar azide with propargyl building block in the presence of copper- (I) catalyst exclusively led to the mono-coupling product in a respectable yield of almost 80%. Besides the unexpected incomplete conversion, the loss of the remaining propargyl group, as indicated by both NMR and MS. On the other hand, application of substantial amounts of CuSO4 under reducing conditions in refluxing toluene/water furnished the alkyne dimer in a moderate yield of 43%, while no change of azide compound was noticed. Results: The Cu(I)-catalyst applied for azide-alkyne cycloadditions enables the homo-coupling of certain terminal alkynes at a higher temperature. Moreover, aromatic propargyl ethers may be cleaved to furnish the corresponding phenol. The copper-catalyzed coupling appeared highly sensitive towards the alkyne compound. Only selected derivatives of propargyl alcohol were successfully dimerized. Conclusions: The observed failure of the Huisgen reaction for the synthesis of sugar-based surfactants may indicate non-recognized constrains of the reaction, which could affect its wide application in bioconjugation. The temperature requirement for the alternative dimerization of terminal alkynes renders this side reaction nonrelevant for typical click couplings, while narrow substrate diversity and moderate yield limit its synthetic application.

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20

Taylor, A. E., K. Taylor, B. Tennigkeit, M. Palatinszky, M. Stieglmeier, D. D. Myrold, C. Schleper, M. Wagner, and P. J. Bottomley. "Inhibitory Effects of C2to C101-Alkynes on Ammonia Oxidation in Two Nitrososphaera Species." Applied and Environmental Microbiology 81, no. 6 (January 9, 2015): 1942–48. http://dx.doi.org/10.1128/aem.03688-14.

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ABSTRACTA previous study showed that ammonia oxidation by theThaumarchaeotaNitrosopumilus maritimus(group 1.1a) was resistant to concentrations of the C81-alkyne, octyne, which completely inhibits activity by ammonia-oxidizing bacteria. In this study, the inhibitory effects of octyne and other C2to C101-alkynes were evaluated on the nitrite production activity of two pure culture isolates fromThaumarchaeotagroup 1.1b,Nitrososphaera viennensisstrain EN76 andNitrososphaera gargensis. BothN. viennensisandN. gargensiswere insensitive to concentrations of octyne that cause complete and irreversible inactivation of nitrite production by ammonia-oxidizing bacteria. However, octyne concentrations (≥20 μM) that did not inhibitN. maritimuspartially inhibited nitrite production inN. viennensisandN. gargensisin a manner that did not show the characteristics of irreversible inactivation. In contrast to previous studies with an ammonia-oxidizing bacterium,Nitrosomonas europaea, octyne inhibition ofN. viennensiswas: (i) fully and immediately reversible, (ii) not competitive with NH4+, and (iii) without effect on the competitive interaction between NH4+and acetylene. BothN. viennensisandN. gargensisdemonstrated the same overall trend in regard to 1-alkyne inhibition as previously observed forN. maritimus, being highly sensitive to ≤C5alkynes and more resistant to longer-chain length alkynes. Reproducible differences were observed amongN. maritimus,N. viennensis, andN. gargensisin regard to the extent of their resistance/sensitivity to C6and C71-alkynes, which may indicate differences in the ammonia monooxygenase binding and catalytic site(s) among theThaumarchaeota.

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21

Seidel, Wolfram W., Matthias J. Meel, and Thomas Lügger. "Das Koordinationsverhalten des Acetylendisulfids Bis(benzylthio)acetylen gegenüber nullwertigen Metallkomplexen des W, Co und Pt/The Coordination Behavior of the Acetylenedisulfide Bis(benzylthio)acetylene with Zero-valent Metal Complexes of W, Co and Pt." Zeitschrift für Naturforschung B 62, no. 5 (May 1, 2007): 669–74. http://dx.doi.org/10.1515/znb-2007-0507.

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Abstract Synthesis and characterization of the alkyne complexes [Co2(CO)6(L)], [W(CO)(L)3] and [Pt(PPh3)2(L)] with L = BnSC2SBn (Bn = benzyl) are described. X-Ray diffraction studies of [W(CO)(L)3] and [Co2(CO)5(L)]2 reveal that the donor ability of the sulfide group depends on the electronic and steric situation in the particular metal complex. The specific donor strength of sulfidesubstituted alkynes in their complexes is discussed considering the IR and NMR spectroscopic data.

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22

Tobita, Hiromi, Nobukazu Yamahira, Keisuke Ohta, Takashi Komuro, and Masaaki Okazaki. "New hydrosilylation reaction of arylacetylene accompanied by C-H bond activation catalyzed by a xantsil ruthenium complex." Pure and Applied Chemistry 80, no. 5 (January 1, 2008): 1155–60. http://dx.doi.org/10.1351/pac200880051155.

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A new type of catalytic hydrosilylation of arylalkynes was induced by a 16-electron ruthenium bis(silyl) phosphine complex, resulting in ortho-silylation of the aryl group as well as a hydrogenation of the alkyne CC bond to give an (E)-form of alkene selectively. On the other hand, the same reaction using a related bis(silyl) complex having an η6-toluene ligand instead of the phosphine ligand as a catalyst led to a normal hydrosilylation reaction to afford silylalkene.

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23

Kawasaki, Yuuya, Youhei Ishikawa, Kazunobu Igawa, and Katsuhiko Tomooka. "Directing Group-Controlled Hydrosilylation: Regioselective Functionalization of Alkyne." Journal of the American Chemical Society 133, no. 51 (December 28, 2011): 20712–15. http://dx.doi.org/10.1021/ja209553f.

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24

Khung, Yit Lung, Siti Hawa Ngalim, Andrea Scaccabarozzi, and Dario Narducci. "Formation of stable Si–O–C submonolayers on hydrogen-terminated silicon(111) under low-temperature conditions." Beilstein Journal of Nanotechnology 6 (January 5, 2015): 19–26. http://dx.doi.org/10.3762/bjnano.6.3.

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In this letter, we report results of a hydrosilylation carried out on bifunctional molecules by using two different approaches, namely through thermal treatment and photochemical treatment through UV irradiation. Previously, our group also demonstrated that in a mixed alkyne/alcohol solution, surface coupling is biased towards the formation of Si–O–C linkages instead of Si–C linkages, thus indirectly supporting the kinetic model of hydrogen abstraction from the Si–H surface (Khung, Y. L. et al. Chem. – Eur. J. 2014, 20, 15151–15158). To further examine the probability of this kinetic model we compare the results from reactions with bifunctional alkynes carried out under thermal treatment (<130 °C) and under UV irradiation, respectively. X-ray photoelectron spectroscopy and contact angle measurements showed that under thermal conditions, the Si–H surface predominately reacts to form Si–O–C bonds from ethynylbenzyl alcohol solution while the UV photochemical route ensures that the alcohol-based alkyne may also form Si–C bonds, thus producing a monolayer of mixed linkages. The results suggested the importance of surface radicals as well as the type of terminal group as being essential towards directing the nature of surface linkage.

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25

Schmalz, Hans-Günther, and Friederike Ratsch. "An Atom-Economic and Stereospecific Access to Trisubstituted Olefins through Enyne Cross Metathesis Followed by 1,4-Hydrogenation." Synlett 29, no. 06 (January 15, 2018): 785–92. http://dx.doi.org/10.1055/s-0036-1591528.

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The combination of intermolecular enyne cross metathesis and subsequent 1,4-hydrogenation opens a stereocontrolled and atom-economic access to trisubstituted olefins. By investigating different combinations of functionalized alkyne and alkene substrates, we found that the outcome (yield, E/Z ratio) of the Grubbs II-catalyzed enyne cross-metathesis step depends on the substrate’s structure, the amount of the alkene (used in excess), and the (optional) presence of ethylene. In any case, the 1,4-hydrogenation, catalyzed by 1,2-dimethoxybenzene-Cr(CO)3, proceeds stereospecifically to yield exclusively the E-products from both the E- and Z-1,3-diene intermediates obtained by metathesis. A rather broad scope and functional group compatibility of the method is demonstrated by means of 15 examples.

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26

Yao, Huan, Xiaoping Wang, Mo Xie, Yu-Mei Wang, Mao Quan, Liu-Pan Yang, and Wei Jiang. "Mono-functionalized derivatives and revised configurational assignment of amide naphthotubes." Organic & Biomolecular Chemistry 18, no. 10 (2020): 1900–1909. http://dx.doi.org/10.1039/d0ob00290a.

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A pair of mono-functionalized amide naphthotubes with one alkyne and three carboxylate groups has been synthesized, and they show different binding behavior from its parent naphthotubes, presumably due to the self-inclusion of the alkyne group.

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27

Tsao, Kelvin K., Ann C. Lee, Karl É. Racine, and Jeffrey W. Keillor. "Site-Specific Fluorogenic Protein Labelling Agent for Bioconjugation." Biomolecules 10, no. 3 (February 28, 2020): 369. http://dx.doi.org/10.3390/biom10030369.

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Many clinically relevant therapeutic agents are formed from the conjugation of small molecules to biomolecules through conjugating linkers. In this study, two novel conjugating linkers were prepared, comprising a central coumarin core, functionalized with a dimaleimide moiety at one end and a terminal alkyne at the other. In our first design, we developed a protein labelling method that site-specifically introduces an alkyne functional group to a dicysteine target peptide tag that was genetically fused to a protein of interest. This method allows for the subsequent attachment of azide-functionalized cargo in the facile synthesis of novel protein-cargo conjugates. However, the fluorogenic aspect of the reaction between the linker and the target peptide was less than we desired. To address this shortcoming, a second linker reagent was prepared. This new design also allowed for the site-specific introduction of an alkyne functional group onto the target peptide, but in a highly fluorogenic and rapid manner. The site-specific addition of an alkyne group to a protein of interest was thus monitored in situ by fluorescence increase, prior to the attachment of azide-functionalized cargo. Finally, we also demonstrated that the cargo can also be attached first, in an azide/alkyne cycloaddition reaction, prior to fluorogenic conjugation with the target peptide-fused protein.

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Kuang, Guanghua, Guangyuan Liu, Xingxing Zhang, Naihao Lu, Yiyuan Peng, Qiang Xiao, and Yirong Zhou. "Directing-Group-Assisted Transition-Metal-Catalyzed Direct C–H Oxidative Annulation of Arenes with Alkynes for Facile Construction of Various Oxygen Heterocycles." Synthesis 52, no. 07 (February 10, 2020): 993–1006. http://dx.doi.org/10.1055/s-0039-1690816.

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The most recent advances in the construction of oxygen heterocycles by the directing-group-assisted transition-metal-catalyzed direct oxidative annulation of arenes with diverse alkynes are summarized in this review. More than 140 recent research papers and many closely related reviews are referenced in this paper. Nine different oxygen heterocycles frameworks are discussed. Several traditional transition-metal catalysts as well as some classical non-noble metals are utilized to promote the annulation. Three plausible controlling models are disclosed to clarify the excellent regioselectivity outcomes achieved in case of unsymmetrical alkyne substrates.1 Introduction2 Coumarins3 I socoumarins and Their Analogues4 2-Pyrones and Their Analogues5 Chromones and Chroman-4-ones6 Chromenes and Isochromenes7 Fused Polycyclic Oxygen Heteroaromatics8 Benzofurans, Dihydrobenzofurans, and Furans9 Phthalides and Benzofuranones10 Benzoxepines11 Conclusion

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29

Zhao, Yiyong, Guangyao Mei, Haibo Wang, Guofu Zhang, and Chengrong Ding. "SO2F2-Promoted Dehydration of Aldoximes: A Rapid and Simple Access to Nitriles." Synlett 30, no. 12 (June 25, 2019): 1484–88. http://dx.doi.org/10.1055/s-0037-1611840.

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A rapid, simple and mild process for the dehydration of aldoximes to give the corresponding nitriles, which utilizes SO2F2 as an efficient reagent, has been developed. A variety of (hetero)arene, alkene, alkyne and aliphatic aldoximes proceeded with high efficiency to afford nitriles in excellent to quantitative yields with great functional group compatibilities in acetonitrile under ambient conditions. Furthermore, an eco-friendly synthetic protocol to access nitriles from aldehydes with ortho-, meta- and para-nitrile groups was also described in aqueous methanol by using inorganic base Na2CO3, and a one-pot synthetic strategy to generate nitriles from aldehydes was proved to be feasible.

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30

Błocka, Aleksandra, and Wojciech Chaładaj. "Tandem Pd-Catalyzed Cyclization/Coupling of Non-Terminal Acetylenic Activated Methylenes with (Hetero)Aryl Bromides." Molecules 27, no. 3 (January 19, 2022): 630. http://dx.doi.org/10.3390/molecules27030630.

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We report a new method for a tandem Pd-catalyzed intramolecular addition of active methylene compounds to internal alkynes followed by coupling with aryl and heteroaryl bromides. Highly substituted vinylidenecyclopentanes were obtained with good yields, complete selectivity, and excellent functional group tolerance. A plausible mechanism, supported by DFT calculations, involves the oxidative addition of bromoarene to Pd(0), followed by cyclization and reductive elimination. The excellent regio- and stereoselectivity arises from the 5-exo-dig intramolecular addition of the enol form of the substrate to alkyne activated by the π-acidic Pd(II) center, postulated as the rate-determining step.

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31

Zhang, Xiaojuan, Xiuling Han, Zhiyong Hu, and Xiyan Lu. "Synthesis of Substituted Piperidines via Cationic Palladium(II)-Catalyzed Reductive Coupling of N-Tosyl-Tethered Alkynones." Synthesis 49, no. 20 (May 3, 2017): 4687–92. http://dx.doi.org/10.1055/s-0036-1588803.

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A cationic palladium(II) complex catalyzed reductive coupling of N-tosyl-tethered alkynones for the synthesis of functionalized piperidines was successfully developed. This reaction was initiated by hydropalladation of the alkyne and quenched by addition to the intramolecular carbonyl group. The substituent on the alkyne is key to the reaction.

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32

Lokare, Kapil S., James T. Ciszewski, and Aaron L. Odom. "Group-6 Imido Activation by a Ring-Strained Alkyne." Organometallics 23, no. 23 (November 2004): 5386–88. http://dx.doi.org/10.1021/om049262q.

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33

Madea, D., T. Slanina, and P. Klán. "A ‘photorelease, catch and photorelease’ strategy for bioconjugation utilizing a p-hydroxyphenacyl group." Chemical Communications 52, no. 87 (2016): 12901–4. http://dx.doi.org/10.1039/c6cc07496k.

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A bioorthogonal strategy, which combines photorelease of a strained alkyne, its cycloaddition withp-hydroxyphenacyl azide to form a 1,2,3-triazole adduct, and subsequent photochemical release of the triazole moietyviaa photo-Favorskii rearrangement, is presented.

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34

Chen, Shuqi, and Bernard L. Flynn. "Iodocyclisation of Electronically Resistant Alkynes: Synthesis of 2-Carboxy (and sulfoxy)-3-iodobenzo[b]thiophenes." Australian Journal of Chemistry 74, no. 1 (2021): 65. http://dx.doi.org/10.1071/ch20218.

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The iodocyclisation of alkynes bearing tethered nucleophiles is a highly effective method for the construction and diversification of heterocycles. A key limitation to this methodology is the 5-endo-dig iodocyclisation of alkynes that have an unfavourable electronic bias for electrophilic cyclisation. These tend to direct electrophilic attack of the iodonium atom to the wrong carbon for cyclisation, thus favouring competing addition reactions. Using our previously determined reaction conditions for the 5-endo-dig iodocyclisations of electronically resistant alkynes, we have achieved efficient synthetic access to 2-carboxy (and sulfoxy)-3-iodobenzo[b]thiophenes. The corresponding benzo[b]furans and indoles were not accessible under these conditions. This difference may arise due to the availability of a radical mechanism in the case of iodobenzo[b]thiophenes. The 2-carboxy functionality of the iodocyclised products can be further employed in iterative alkyne-coupling iodocyclisation reactions, where the carboxy group or an imine (Schiff base) partakes in a second iodocyclisation to generate a lactone or pyridine ring.

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35

Baimbridge, CW, RS Dickson, GD Fallon, I. Grayson, RJ Nesbit, and J. Weigold. "Some Substituent Effects in the Formation of Binuclear Metalladienes and 1,2-Dimetallacycloheptadienones From Reactions Between (η-C5H5)2Rh2(μ-CO)(CF3C2CF3) and Alkynes." Australian Journal of Chemistry 39, no. 8 (1986): 1187. http://dx.doi.org/10.1071/ch9861187.

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The reaction between (η-C5H5)2Rh2(CO)(CF3C2CF3)(1) and alkynes, RC=CR′, can proceed by two alternative pathways. One gives the complexes (η- C5H5)2Rh2{C4(CF3)2RR′CO} (2) in which a pentadienone unit bridges the Rh - Rh bond. The other produces the binuclear metalladiene complexes (η-C5H5)2Rh2{C4(CF3)2RR?} (3) plus the dicarbonyl complex (η-C5H5)2Rh2(CO)2(CF3C2CF3) (4). The formation of (2) is strongly favoured with the dialkylacetylenes BuC≡CBu and MeC =CR (R = Et, Pri, But). With the unsymmetrical acetylenes, two isomers of (2) are isolated. The tendency to form (3) + (4) increases when there are electron-withdrawing substituents such as CN on the alkyne, and becomes dominant when the alkyne is polar (e.g. MeC≡CR with R = Ph, CF3 or CO2Me). The reactions with MeC≡CR are highly regioselective, with only one of the two possible regioisomers being isolated in each case. This has the methyl group in the 3-position of the metalladiene ring. Unexpected products formed in the reactions with MeC≡Cet and MeC≡CPri have been characterized by X-ray crystallography. One is a 1,2- dimetallacycloheptadienone complex, (η-C5H5)2Rh2{C4(CF3)2Me(CMe2OH)CO}. The compound crystallizes with 16 molecules in the orthorhombic space group Fdd2 in a unit cell of dimensions a 31.728(15), b 27.923(14), c 9.275(5) Ǻ. The structure was solved by heavy atom methods and refined to R 0.037 based on 2644 observed reflections. The CMe2(OH) group is adjacent to the carbonyl in the bridging group. The other is a binuclear metalladiene complex (η-C5H5)2Rh2{C4(CF3)2Me( COMe )}. It crystallizes with eight molecules in the orthorhombic space group P bca in a unit cell of dimensions a 17.349(8), b 15.819(8), c 13.720(7) Ǻ. The structure was solved by heavy atom methods and refined to R 0.053 based on 3045 observed reflections above background. The acyl group is adjacent to the metal in the metalladiene ring. These two complexes are formed from (1) and impurities present in the alkynes.

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36

Pradhan, Tapas R., and Jin Kyoon Park. "An Overview of Water‐Mediated Alkyne Functionalization by Neighboring Group Participation of Carbonyl Groups." Advanced Synthesis & Catalysis 362, no. 22 (October 8, 2020): 4833–60. http://dx.doi.org/10.1002/adsc.202000826.

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37

Weiss, Henning, Jeannine Reichel, Helmar Görls, Kilian Rolf Anton Schneider, Mathias Micheel, Michael Pröhl, Michael Gottschaldt, Benjamin Dietzek, and Wolfgang Weigand. "Curcuminoid–BF2 complexes: Synthesis, fluorescence and optimization of BF2 group cleavage." Beilstein Journal of Organic Chemistry 13 (October 26, 2017): 2264–72. http://dx.doi.org/10.3762/bjoc.13.223.

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Eight difluoroboron complexes of curcumin derivatives carrying alkyne groups containing substituents have been synthesized following an optimised reaction pathway. The complexes were received in yields up to 98% and high purities. Their properties as fluorescent dyes have been investigated. Furthermore, a strategy for the hydrolysis of the BF2 group has been established using aqueous methanol and sodium hydroxide or triethylamine.

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38

Shamim, Anwar, Stanley Vasconcelos, Isadora de Oliveira, Joel Reis, Daniel Pimenta, Julio Zukerman-Schpector, and Hélio Stefani. "Synthesis of Glycosyl Azides and Their Applications Using CuAAC Click Chemistry to Generate Bis- and Tris(triazolyl)glycosyl Derivatives." Synthesis 49, no. 23 (August 10, 2017): 5183–96. http://dx.doi.org/10.1055/s-0036-1589090.

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2,3-Unsaturated C-(triazolyl)glycosyl acetates have been synthesized from 3,4,6-tri-O-acetyl-d-glucal using C-glycosylation and click chemistry and were then used in a palladium-catalyzed Tsuji–Trost type allylic azidation reaction to afford the corresponding regioisomeric glucal-azide derivatives. Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions with these glucal-based allylic azides using CuI as the catalyst, led to the corresponding glucal-based bis(triazole) derivatives. Performing further functional group modification and another click (CuAAC) reaction with each of these bis(triazolyl) glycosyl derivatives afforded tris(triazolyl)glycosyl derivatives. Two libraries of regioisomeric bis(triazole) derivatives and a small library of regioisomeric tris(triazole) derivatives of glucal were then synthesized using different alkynes.

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39

Cowley, Michael J., Jason M. Lynam, and Adrian C. Whitwood. "Rhodium vinylidene and alkyne complexes containing a pendant uracil group." Journal of Organometallic Chemistry 695, no. 1 (January 2010): 18–25. http://dx.doi.org/10.1016/j.jorganchem.2009.09.020.

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40

Baker, Murray V., and Simon K. Brayshaw. "Synthesis of Tungsten Complexes Containing an Intramolecularly Coordinated Alkyne Group." Organometallics 23, no. 15 (July 2004): 3749–51. http://dx.doi.org/10.1021/om049841v.

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41

Kaneta, Naotake, Tomoe Hirai, and Miwako Mori. "Reaction of Alkyne Having Hydroxyphenyl Group with Mo(CO)6." Chemistry Letters 24, no. 8 (August 1995): 627–28. http://dx.doi.org/10.1246/cl.1995.627.

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42

Kawasaki, Yuuya, Youhei Ishikawa, Kazunobu Igawa, and Katsuhiko Tomooka. "ChemInform Abstract: Directing Group Controlled Hydrosilylation: Regioselective Functionalization of Alkyne." ChemInform 43, no. 22 (May 3, 2012): no. http://dx.doi.org/10.1002/chin.201222162.

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43

Power, Philip P. "Bonding and Reactivity of Heavier Group 14 Element Alkyne Analogues." Organometallics 26, no. 18 (August 2007): 4362–72. http://dx.doi.org/10.1021/om700365p.

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44

Kumar, Jatin N., Yun-Long Wu, Xian Jun Loh, Nicholas Y. Ho, Shalen X. Aik, and Victoria Y. Pang. "The effective treatment of multi-drug resistant tumors with self-assembling alginate copolymers." Polymer Chemistry 10, no. 2 (2019): 278–86. http://dx.doi.org/10.1039/c8py01255e.

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45

Swidersky, Hans-Walter, Jürgen Pebler, Kurt Dehnicke, and Dieter Fenske. "Acetylenkomplexe von Rhenium(+ VI). Die Kristallstrukturen von [ReCl4(n-C3H7 – C= C – n-C3H7)(POCl3)] und ReCl4(THF)2 / Alkyne Complexes of Rhenium(+VI). The Crystal Structures of [ReCl4(n-C3H7 – C= C – n-C3H7)(POCl3)] and ReCl4(THF)2." Zeitschrift für Naturforschung B 45, no. 9 (September 1, 1990): 1227–34. http://dx.doi.org/10.1515/znb-1990-0902.

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The results of the magnetic susceptibility measurements of the previously reported rhenium alkyne complexes [ReCl4(PhC≡CPh)]2.2 CH2Cl2 and [ReCl4(PhC=CPh)(CH3CN)] in the temperature range of 4.2-293 K suggest d1-configurations, corresponding with oxidation state +VI for the rhenium atoms. The new alkyne complex [ReCl4(n-C3H7–C=C–n-C3H7)(POCl3)] has been prepared by the reaction of ReCl5·OPCl3 with n-C3H7-C≡C–n-C3H7 in CCl4 solution, forming dark red single crystals, which were characterized by IR spectroscopy as well as by a crystal structure determination with X-ray methods (space group P2,/c, Z = 4, 3235 observed unique reflexions, R = 0.026; lattice dimensions at –70 °C: a = 805.6(2), b = 1000.6(4), c = 2188.8(6) pm, β = 79.59(2)°). [ReCl4(n-C3H7-C=C–n-C3H7)(POCl3)] has a molecular structure with the alkyne ligand bonded side-on (bond lengths Re-C 198.4 and 198.2(5) pm). The oxygen atom of the solvating POCl3 molecule is coordinated in trans position to the ReC2 unit of the alkyne ligand (bond length Re—O = 223.7(3) pm).In THF solutions the alkyne complexes of this type undergo a slow reaction forming ReCl4(THF)2, which was also characterized by IR spectroscopy and a crystal structure determination (space group P212121, Z = 4, 2243 observed unique reflexions, R = 0.053; lattice dimensions at –70 °C: a = 773.0(14), b = 1267.1(6), c = 1398.6(7) pm). In ReCl4(THF)2 the THF molecules coordinate in cis-position (bond lengths Re–O 208 and 212(1) pm).

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46

Velasco, Bayardo E., Gustavo López-Téllez, Nelly González-Rivas, Iván García-Orozco, and Erick Cuevas-Yañez. "Catalytic activity of dithioic acid copper complexes in the alkyne–azide cycloaddition." Canadian Journal of Chemistry 91, no. 4 (April 2013): 292–99. http://dx.doi.org/10.1139/cjc-2012-0325.

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Diverse dithioic acid copper complexes exhibit a high catalytic activity in the copper-catalyzed alkyne–azide cycloaddition using several solvents under different temperatures, showing a high efficiency with only 0.005 mmol catalyst/mmol alkyne or less. A dithioic acid copper complex derived from acetophenone was selected and used as the catalyst in the preparation of a library of 1,4-disubstituted-1,2,3-triazoles. This process occurred in high yields and good functional group tolerance.

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47

Neumann, Petra, Kurt Dehnicke, Dieter Fenske, and Gerhard Baum. "Fluoro-, Chloro- und Bromo-Wolfram(VI)-Alkinkomplexe. Die Kristallstrukturen von [K(18-Krone-6)][WF5(Ph – C≡C – H)] · CH3CN und [WCl4(Ph – C ≡ C – Se – n – C4H9)(CH3CN)] / Fluoro-, Chloro-, and Bromo-Tungsten(VI) Alkyne Complexes. The Crystal Structures of [K(18-Crown-6)][WF5(Ph — C ≡ C — H)] · CH3CN and [WCl4(Ph — C ≡ C — Se — n — C4H9)(CH3CN)]." Zeitschrift für Naturforschung B 46, no. 8 (August 1, 1991): 999–1010. http://dx.doi.org/10.1515/znb-1991-0805.

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Several tungsten alkyne complexes of the type [WCl4(R – C ≡ C – H)]2 and [WCl4(R – C ≡ C — R′)]2 have been prepared by reactions of WCl6 with the alkynes in the presence of C2Cl4. Treating with BrSiMe3 leads to corresponding bromo complexes, whereas reactions of NaF and KF, respectively, in acetonitrile solution in the presence of crown ethers yield the fluoro complexes [Na(15-crown-5)][WF5(R – C ≡ C – R′)] and [K(18-crown-6)][WF5(R – C ≡ C – R ′)], respectively. All complexes were characterized by IR and 13C NMR spectroscopy. The crystal structures of [K(18-crown-6)][WF5(Ph – C ≡ C – H)] · CH3CN and [WCl4(Ph – C ≡ C – Se – n – C4H9)(CH3CN)] have been determined by X-ray methods.[K(18-crown-6)][WF5(Ph – C ≡ C – H] · CH3CN: Space group P21 Z = 2, 8555 observed unique reflections, R = 0.034. Lattice dimensions at -70 °C: a = 1199.4(3), b = 893.4(2), c = 1351.8(3) pm, β = 109.73(3)°. The compound forms ion pairs via three K – F contacts with bond lengths of 262.0, 282.7, and 293.3 pm; the potassium ion is thus nine-fold coordinated by the six oxygen atoms of the crown ether molecule and by three fluoride ligands. The alkyne ligand is bonded side on to the tungsten atom of the [WF5(Ph – Cs ≡ C – H)]- unit with WC bond lengths of 202.4 and 202.6 pm, respectively.[WCl4(Ph – C ≡ C – Se – n – C4H9)(CH3CN)]: Space group P21/a, Z = 4,4595 observed unique reflections, R = 0.058. Lattice dimensions at -70 °C: a = 1030.3(5), b = 1596.3(9), c = 1170.9(7) pm, β = 104.28(3)°. The compound has a molecular structure, in which the tungsten atom is seven-fold coordinated by four chloride ligands, by the two alkyne carbon atoms (WC bond lengths 200 and 203 pm), and in trans position to the latter by the nitrogen atom of the acetonitrile molecule with a W – N bond length of 226 pm.

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48

B. Lade, Diksha, Dayanand P. Gogle, and Bipin D. Lade. "Development of Silver Nanoparticles/PEG/Glycerine Composite for Antibacterial Effect using Leaf Extract of Ocimum sanctum and Ocimum basilicum." Volume 4,Issue 5,2018 4, no. 5 (November 12, 2018): 527–32. http://dx.doi.org/10.30799/jnst.161.18040517.

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The main purpose of the experiment is to use green synthesis method for silver nanoparticles (SNP) fabrication using phytochemical and functional groups inherent in aqueous leaf extract of Ocimum sanctum and Ocimum basilicum for formulation of polyethylene glycol (PEG)/ Glycerine film. The SNP synthesis reaction is performed under sun condition and change in colour from light brown to dark brown was the initial indication, observed for nanoparticles synthesis. The 95 mL of 0.001 M AgNO3 is mixed with 5 mL of leaf extract and reaction performed under Sun light at alkaline pH 8 was found efficient to produced stable NP. The synthesized SNP are mixed with (10%, 50%, 100%, 150%, 200% and 250%), polyethylene glycol (PEG):glycerine (G) in 1:1 ratio to form a film. The UV-spectroscopic analysis confirms absorption at 420-430 nm for synthesized SNP. The FTIR characterization determines alkynes (terminal), 1�, 2� amines, amides, nitriles, alkynes, alkyl halides functional group from O. sanctum (OS) leaf extract and aldehydes, alkynes (terminal), alkyne, alkene, from O. basilicum (OB) leaf extract responsible for reducing and capping silver nitrate to form nanoparticles. The SEM analysis verify that the O. sanctum based nanoparticles are spherical in shape although O. basilicum based nanoparticles have bright contrast coral reef like morphology. The average zeta potential of silver nanoparticles was found to be 27.74 mV and 23.50 mV that are embedded in Ocimum sanctum-SNP/PEG and Ocimum basilicum-SNP/PEG films. Also, the average diameters of SNP in Ocimum sanctum-SNP/PEG and in Ocimum basilicum-SNP/PEG was found to be 463.2 nm and 43.0 nm. These Sun light mediated SNP shows antimicrobial activity against E. coli and S. aureous pathogens.

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49

Druzina, Anna A., Olga B. Zhidkova, Nadezhda V. Dudarova, Natalia A. Nekrasova, Kyrill Yu Suponitsky, Sergey V. Timofeev, and Vladimir I. Bregadze. "Synthesis of Zwitter-Ionic Conjugate of Nido-Carborane with Cholesterol." Molecules 26, no. 21 (November 5, 2021): 6687. http://dx.doi.org/10.3390/molecules26216687.

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9-HC≡CCH2Me2N-nido-7,8-C2B9H11, a previously described carboranyl terminal alkyne, was used for the copper(I)-catalyzed azide-alkyne cycloaddition with azido-3β-cholesterol to form a novel zwitter-ionic conjugate of nido-carborane with cholesterol, bearing a 1,2,3-triazol fragment. The conjugate of nido-carborane with cholesterol, containing a charge-compensated group in the linker, can be used as a precursor for the preparation of liposomes for BNCT (Boron Neutron Capture Therapy). The solid-state molecular structure of a nido-carborane derivative with the 9-Me2N(CH2)2Me2N-nido-7,8-C2B9H11 terminal dimethylamino group was determined by single-crystal X-ray diffraction.

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50

Cowie, Martin. "2003 Alcan Award Lecture Roles of the adjacent metals in the coupling of methylene groups promoted by heterobinuclear complexes of Group 8 and 9 metals." Canadian Journal of Chemistry 83, no. 8 (August 1, 2005): 1043–55. http://dx.doi.org/10.1139/v05-122.

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The reactivities of the heterobinuclear complexes, [MM′(CO)4(dppm)2][X] (MM′ = RhOs, RhRu, IrRu; dppm = µ-Ph2PCH2PPh2; X = BF4, CF3SO3) with diazomethane are reported. The RhOs species reacts to give three products of methylene-group incorporation, depending on the temperature; at 80 °C the methylene bridged product, [RhOs(CO)4(µ-CH2)(dppm)2][X], is formed exclusively, at ambient temperature only [RhOs(η1-C3H5)(CH3)(CO)3(dppm)2][X], having the allyl group bound to Rh and the methyl group bound to Os, is obtained, while at intermediate temperatures [RhOs(η1:η1-C4H8)(CO)3(dppm)2][X], having the butanediyl fragment chelating on Os, is generated. Based on labeling studies a mechanism is proposed rationalizing formation of the different products. Under the same range of conditions the Rh/Ru and Ir/Ru species yield only the methylene bridged products, [MM′(CO)4(µ-CH2)(dppm)2][X] (MM′ = RhRu, IrRu). A rationalization for the different reactivities observed and a description of the roles of the different metals in coupling of the methylene groups are presented. Attempts to model key intermediates in the methylene coupling sequence promoted by the Rh/Os complexes, through coupling of methylene groups with ethylene or alkynes, are described. Key words: heterobinuclear, rhodium/osmium, rhodium/ruthenium, iridium/ruthenium, methylene coupling, FischerTropsch, alkyne insertions, bimetallic cooperativity.

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