- Features of the mechanism of oxidative dehydrodimerization of propynol
-
Analysis of kinetic regularities for the propynol oxidative coupling under the action of cupric salts in pyridine and in the presence of a buffer is undertaken. The reaction mechanism, including the formation of Cu(I) acetylides, is considered.
- Fedenok, Lidiya G.,Shvartsberg, Mark S.
-
-
Read Online
- Mechanistic investigation and further optimization of the aqueous Glaser-Hay bioconjugation
-
The Glaser-Hay bioconjugation has recently emerged as an efficient and attractive method to generate stable, useful bioconjugates with numerous applications, specifically in the field of therapeutics. Herein, we investigate the mechanism of the aqueous Glaser-Hay coupling to better understand optimization strategies. In doing so, it was identified that catalase is able to minimize protein oxidation and improve coupling efficiency, suggesting that hydrogen peroxide is produced during the aqueous Glaser-Hay bioconjugation. Further, several new ligands were investigated to minimize protein oxidation and maximize coupling efficiency. Finally, two novel strategies to streamline the Glaser-Hay bioconjugation and eliminate the need for secondary purification have been developed.
- Travis, Christopher R.,Mazur, Lauren E.,Peairs, Emily M.,Gaunt, Gillian H.,Young, Douglas D.
-
-
Read Online
- First total synthesis of acetylenic alcohol 15-methyltricosa-2,4-diyne-1, 6-diol (strongylodiol-G) derived from marine sponge
-
The first total and efficient synthesis of a naturally occurring acetylenic alcohol 15-methyltricosa-2,4-diyne-1,6-diol (strongylodiol-G) derived from marine sponge involving nine steps has been described. 1-Bromo-9- methyloctadecane (5) and hex-6-tetrahydropyranyloxyhex-2,4-diyn-1-al (9) which were initially synthesised separately starting from 1,8-octanediol (1) and propargyl alcohol (6), respectively, have been used as the final intermediates to obtain the title compound. The key steps in the synthesis involved ionic liquid-mediated bromination of 1,8-octanediol (1), tetrahydropyranylation of 8-bromooctan-1-ol (2) using acidic ionic liquid [bmim]HSO4 and monotetrahydropyranylation of hex-2,4-yn-1,6-diol (7) using ultrasonic energy.
- Gupta, Neeraj,Shallu,Kad, Goverdhan Lal,Singh, Jasvinder
-
-
Read Online
- Glaser coupling reaction in supercritical carbon dioxide
-
It is demonstrated for the first time that Glaser coupling can be carried out smoothly in supercritical carbon dioxide using a solid base (NaOAc) instead of amines.
- Li, Jinheng,Jiang, Huanfeng
-
-
Read Online
- Noncatalytic, solvent-free thermal formation of cyclic trimers using 1,6-bis(acyloxymethyl)hexa-2,4-diyne derivatives
-
The thermal reactivity of diacetylenes in the liquid phase was studied extensively to elucidate the cooperative mechanism of polymerization.
- Taniguchi, Shin-Ichi,Yokoi, Toshihiro,Izuoka, Akira,Matsushita, Michio M.,Sugawara, Tadashi
-
-
Read Online
- Catalytically active self-assembled silica-based nanostructures containing supported nanoparticles
-
Self-assembled tubular silica-based nanostructures can be prepared using a simple, low-energy intensive and benign protocol under mild conditions (100 °C) using microwave irradiation and conventional heating. These nanotubes were found to contain metal nanoparticles that are catalytically active in the microwave-assisted homocoupling of terminal alkynes. The Royal Society of Chemistry 2010.
- Gonzalez-Arellano, Camino,Balu, Alina Mariana,Luque, Rafael,MacQuarrie, Duncan J.
-
-
Read Online
- Glaser oxidative coupling in ionic liquids: An improved synthesis of conjugated 1,3-diynes
-
Terminal alkynes undergo oxidative-coupling smoothly in the presence of the CuCl-TMEDA catalytic system in hydrophobic [bmim]PF6 ionic liquid under aerobic conditions to produce 1,3-diynes in excellent yields under mild conditions. The substrates, alkynes, show enhanced reactivity and selectivity in ionic liquids (ILs). The recovery of the catalyst is facilitated by the hydrophobic nature of the [bmim]PF6 ionic liquid.
- Yadav,Reddy,Reddy, K. Bhaskar,Gayathri, K. Uma,Prasad
-
-
Read Online
- Leaf-like CuO nanosheets on rGO as an efficient heterogeneous catalyst for Csp-Csp homocoupling of terminal alkynes
-
In this work, the economic and well-defined leaf-like CuO nanosheets on rGO (CuO nanosheets/rGO) was synthesized by a convenient hydrothermal method. The morphology and chemical composition of CuO nanosheets/rGO were confirmed by XRD, SEM-EDS, TEM, HR-TEM, and XPS techniques. The CuO nanosheets/rGO was successfully applied as a high-performance heterogeneous catalyst in the homocoupling of 12 terminal alkynes, and the isolated yield of each product was more than 80%, except for propargyl alcohol. This catalyst could be reused five times with little activity loss. Thus, it is beneficial for green and sustainable development of organic synthetic chemistry.
- Gao, Lingfeng,Wang, Bin,Zheng, Gengxiu
-
-
- In the optically-multiplexed-
-
A method for optical super-multiplexing using polyynes to provide enhanced images from stimulated Raman microscopy is disclosed. In some exemplary embodiments, the polyynes are organelle-targeted or spectral barcoded. Imaging can be enhanced by using the polyynes to image whole live cells or specific organelles within live cells. The polyynes can also be used in optical data storage (i.e., encoding) and identification (i.e., decoding) applications.
- -
-
Paragraph 0216; 0217
(2020/12/30)
-
- Synthesis of ene-yne-enes by nickel-catalyzed double SN2′ substitution of 1,6-dichlorohexa-2,4-diyne
-
1,6-Dichlorohexa-2,4-diyne undergoes nickel-catalyzed double substitution with aryl and alkenyl Grignard reagents to provide substituted ene-yne-enes. The reaction is formally an extension of the well-described SN2′-allylic and -propargylic substitution reactions but the mechanism is considerably more complex. The products might function as building blocks for conjugated polymers.
- Wang, Gongbao,Lindeboom, Erik-Jan,Van Heerewaarden, Chris,Minnaard, Adriaan J.
-
p. 2347 - 2355
(2017/07/22)
-
- Diacetylene-Based C 2h-Symmetric Monomers for Two-Dimensional-Polymer Synthesis
-
Two linear monomers with two terminal photoreactive groups (anthracene or maleimide) embedded in a diacetylene skeleton were synthesized for two-dimensional-polymer synthesis. Both of them were crystallized and their single-crystal structures were solved. It was found that the size of terminal groups can be critical for diacetylene's arrangement. The crystal structure of dimaleimide monomer revealed that maleimide groups strongly stacking in antiparallel and the photo-induced [2+2] cycloaddition of stacked maleimides was preliminary studied.
- Song, Mengyao,Ma, Hanbing,Ren, Minghan,Ai, Zhaoquan,Li, Ming
-
supporting information
p. 445 - 450
(2017/02/24)
-
- Copper catalyzed oxidative homocoupling of terminal alkynes to 1,3-diynes: A Cu3(BTC)2 MOF as an efficient and ligand free catalyst for Glaser-Hay coupling
-
A straightforward and efficient method has been demonstrated for the oxidative coupling of terminal alkynes using a simple Cu3(BTC)2-metal organic framework as a sustainable heterogeneous copper catalyst. A series of symmetrical 1,3-diynes bearing diverse functional groups have been synthesized in moderate to excellent yields via a Cu3(BTC)2 catalyzed Glaser-Hay reaction. The presence of the coordinatively unsaturated open CuII sites in Cu3(BTC)2 catalyzes the homocoupling in the presence of air, as an environment friendly oxidant without the use of external oxidants, ligands or any additives. The present methodology avoids stoichiometric reagents and harsher or special reaction conditions, and shows good functional group tolerance. The as-prepared catalyst could be separated easily by simple filtration and reused several times without any notable loss in activity. The hot filtration test has investigated the true heterogeneity of the catalyst. Additionally, the powder X-ray diffraction pattern of the reused catalyst revealed the high stability of the catalyst.
- Devarajan, Nainamalai,Karthik, Murugan,Suresh, Palaniswamy
-
p. 9191 - 9199
(2017/11/14)
-
- NNN-pincer-copper complex immobilized on magnetic nanoparticles as a powerful hybrid catalyst for aerobic oxidative coupling and cycloaddition reactions in water
-
A simple and reliable methodology is described for preparing the first heterogeneous NNN-pincer-copper hybrid catalyst with a high control over surface composition. The strategy relies on the covalently bonding of 2-aminopyridine to cyanuric chloride-functionalized magnetic nanoparticles followed by complexation with CuI. These claims are confirmed by different characterization methods such as SEM, TEM, FT-IR, TGA, ICP, XRD, and elemental analysis. The finely engineered supported catalyst is employed in the aerobic oxidative coupling of terminal alkynes and click reaction using only 0.38 and 0.04 mol% catalyst, respectively. All reactions perform under solvent-free condition or green solvent H2O. Also, the catalyst is readily recovered and reused for up to 8 and 6 subsequent runs in click and homocoupling reactions without significant loss of activity or leaching.
- Zohreh, Nasrin,Jahani, Mahboobeh
-
p. 117 - 129
(2016/12/07)
-
- COMPOUNDS AND METHODS FOR THE TARGETED DEGRADATION OF BROMODOMAIN-CONTAINING PROTEINS
-
The present invention relates to bifunctional compounds, which find utility as modulators of targeted ubiquitination, especially inhibitors of a variety of polypeptides and other proteins which are degraded and/or otherwise inhibited by bifunctional compounds according to the present invention. In particular, the present invention is directed to compounds, which contain on one end a VHL ligand which binds to the ubiquitin ligase and on the other end a moiety which binds a target protein such that the target protein is placed in proximity to the ubiquitin ligase to effect degradation (and inhibition) of that protein. The present invention exhibits a broad range of pharmacological activities associated with compounds according to the present invention, consistent with the degradation/inhibition of targeted polypeptides.
- -
-
Paragraph 00283; 00284
(2017/03/21)
-
- CuSCN-mediated homocoupling of terminal alkynes to 1,3-diynes using 4-nitrobenzenediazonium tetrafluoroborate as oxidant
-
Eleven 1,3-diynes have been prepared by a highly efficient base-catalysed homocoupling of terminal alkynes mediated by a novel combination of CuSCN/4-nitrobenzenediazonium tetrafluoroborate.
- Liu, Haidong,Chen, Bo,Cai, Jin,Chen, Junqing,Ji, Min
-
p. 335 - 337
(2016/07/06)
-
- A New Multicomponent Multicatalyst Reaction (MC)2R: Chemoselective Cycloaddition and Latent Catalyst Activation for the Synthesis of Fully Substituted 1,2,3-Triazoles
-
A multicomponent multicatalyst reaction (MC)2R for constructing fully substituted 1,2,3-triazoles is reported. An application of chemoselectivity and latent catalysis in a sequence of multicatalytic reactions confers control over a number of undesired processes, where all of the reagents coexist in the same reaction vessel. The sequence of a chemoselective copper-catalyzed azide alkyne cycloaddition followed by a palladium/copper-catalyzed Sonogashira cross-coupling afforded 1,2,3-triazoles regioselectively with good to high yields and a broad scope.
- Yamamoto, Kosuke,Bruun, Theodora,Kim, Jung Yun,Zhang, Lei,Lautens, Mark
-
supporting information
p. 2644 - 2647
(2016/06/15)
-
- Synthesis of 21,23-selenium- and tellurium-substituted 5-porphomethenes, 5,10-porphodimethenes, 5,15-porphodimethenes, and porphotrimethenes and their interactions with mercury
-
The 3+1 condensation of symmetrical 16-Selena/telluratripyrranes with symmetrical selenophene-2,5-diols/tellurophene-2,5-diols in the presence of BF3-etheratre or BF3-methanol followed by oxidation with DDQ gave 5,10-porphodimethenes, whereas the process with unsymmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave 5-porphomethenes. In addition, the reaction of unsymmetrical 16-Selena/telluratripyrranes with symmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave the corresponding porphotrimethenes, whereas the process with unsymmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave the 5,15-porphodimethenes. The structures of different products were characterized by IR, 1H and 13C NMR, 1H-1H COSY, CHN analysis, and mass spectrometry. The binding of mercury with the calix[4]phyrins mentioned above had been observed in the decreasing order of porphodimethenes > porphomethenes > porphotrimethenes by UV-vis and 1H NMR spectroscopy.
- Ahmad, Sohail,Yadav, Kumar Karitkey,Bhattacharya, Soumee,Chauhan, Prashant,Chauhan
-
p. 3880 - 3890
(2015/04/27)
-
- Optimization of solid-supported Glaser-Hay reactions in the microwave
-
The translation of organometallic reactions into a microwave reactor has numerous advantages. Herein, we describe the application of a previously developed solid-supported Glaser-Hay reaction to microwave conditions. Overall, an array of diynes has been prepared demonstrating the ability to conduct chemoselective reactions in the microwave within 20 min compared to the 16 h thermal conditions. Moreover, non-microwave transparent alkynes have been found to react more quickly, preventing catalyst quenching, and resulting in higher yields.
- Lampkowski, Jessica S.,Maza, Johnathan C.,Verma, Sanjana,Young, Douglas D.
-
p. 5276 - 5285
(2015/05/13)
-
- Synthesis of 5,10,15,20-meso-unsubstituted and 5,10,15,20-meso-substituted- 21,23-ditellura/diselena core-modified porphyrinogens: Oxidation and detection of mercury(ii)
-
Tellurium and selenium incorporated 5,10,15,20-meso-unsubstituted-21,23- ditellura/diselena core-modified porphyrinogens (N2Te2 and N2Se2), 5,10,15,20-meso-unsubstituted-21-tellura/selena core-modified porphyrinogens (N3Te and N3Se) and fully substituted meso-carbons porphyrinogens (N2Te2, N 2Se2 and higher analogs) are synthesized by 3 + 1 condensation of tellurophene/selenophene dipyrranes and their corresponding diols in the presence of BF3-etharate or BF3-methanol. The meso-unsubstituted and substituted porphyrinogens were oxidized with chloranil/0.1% aqueous FeCl3 in CHCl3 at room temperature to obtain the corresponding porphines and porphyrins which are further reduced to corresponding chlorin and bacteriochlorin, whereas the fully meso-substituted porphyrinogens were found to be good ligands for Hg2+. The structures of the products were characterized by IR, 1H, 13C, 125Te, 77Se NMR, CHN analysis, mass spectrometry and single-crystal XRD.
- Ahmad, Sohail,Yadav, Kumar Karitkey,Singh, Sarangthem Joychandra,Chauhan
-
p. 3171 - 3180
(2014/01/06)
-
- Preparation of asymmetrical polyynes by a solid-supported Glaser-Hay reaction
-
Polyynes exhibit both unique photophysical properties and biological activities, necessitating efficient syntheses towards these core structures. A novel methodology for the construction of highly conjugated asymmetrical polyynes has been developed in a chemoselective fashion utilizing a solid-support. The synthesis has been applied to prepare a small library of polyynes in good to moderate yield. Moreover, their interesting fluorescence properties have been investigated, demonstrating the ability to tune fluorescence through selection of appropriate synthetic building blocks. This journal is
- Lampkowski, Jessica S.,Durham, Corinn E.,Padilla, Marshall S.,Young, Douglas D.
-
supporting information
p. 424 - 427
(2015/02/05)
-
- Development of solid-supported Glaser-Hay couplings
-
While the Glaser-Hay coupling of terminal alkynes is a useful reaction, several issues associated with chemoselectivity preclude its widespread application in synthetic chemistry. To address these issues, a solid-supported Glaser-Hay methodology was developed to afford only asymmetric diyne products. This methodology was then applied to a series of immobilized alkynes with a diverse set of soluble alkynes to generate an array of heterocoupled products in high yields and purities.
- Tripp, Valerie T.,Lampkowski, Jessica S.,Tyler, Ryan,Young, Douglas D.
-
supporting information
p. 164 - 167
(2014/05/06)
-
- Palladium(II)-copper(I) mediated homotrimerization and homotetramerization of terminal alkynes
-
Alkyne homocoupling is commonly observed in cross coupling reactions; however, self trimerization and homotetramerization of alkynes to form branched products through cross-coupling reactions are rarely reported. We describe herein homotrimerization and h
- Yalagala, Ravi Shekar,Zhou, Ningzhang,Yan, Hongbin
-
supporting information
p. 1883 - 1885
(2014/03/21)
-
- Cu (I) immobilized on functionalized SBA-15: A recyclable catalyst for the synthesis of 1,3-diynes using terminal alkynes without base
-
A new functionalized SBA-15 catalyst immobilized CuI was successfully prepared, and the catalytic activity was tested in the oxidative homocoupling of terminal alkynes at the absence of base, and good to excellent yields was obtained to get 1,3-diynes without any side product formation in the solution of DMSO. Moreover, the system also allowed the synthesis of unsymmetric 1,3-diynes by cross-coupling of two different terminal alkynes. Finally, the catalyst could be reused for several times without a significant loss of activity.
- Ma, Zongyan,Wang, Xiaoyu,Wei, Shuoyun,Yang, Honglei,Zhang, Fengwei,Wang, Peng,Xie, Miao,Ma, Jiantai
-
-
- An iterative method for the synthesis of symmetric polyynes
-
An iterative synthetic route for obtaining symmetric polyynes was developed, consisting of a series of iodination and Stille coupling reactions. The starting materials employed in this pathway are simple and can be prepared easily. Polyynes containing up to seven Ca=C bonds were synthesized using this method. This route is particularly effective for accessing polyynes with an odd number of Ca=C bonds and has allowed for the synthesis of a new iodine-capped polyyne, diiododecapentayne. Copyright
- Decicco, Racquel C.,Black, Allison,Li, Lei,Goroff, Nancy S.
-
scheme or table
p. 4699 - 4704
(2012/10/08)
-
- Bergman cyclization of fluorinated benzo-fused enediynes to naphthalene derivatives: Syntheses and structures
-
Fluorinated naphthalene derivatives were prepared by Bergman cyclization of fluorinated benzo-fused enediynes. This route provides access to the aromatic target compounds in a two-step procedure from commercially available precursors, via a Sonogashira cross-coupling and a subsequent, thermally initiated Bergman cyclization. Crystal structures of six fluorinated benzo-enediynes and three fluorinated naphthalene derivatives display significant diversity in their molecular structures and in the crystal packing arrangements. The rather subtle structural change from di- to tetrafluorobenzo-enediynes, as well as the variation in the terminal acetylene subunit led to different non-covalent interactions in the solid state that ultimately govern their crystal structures. Fluorinated naphthalene derivatives were obtained from a series of di- and tetrafluorinated benzo-fused enediyne precursors, readily available by Sonogashira cross-coupling. The crystal structures of six fluorinated benzo-enediynes and of three fluorinated naphthalenes show how acombination of non-covalent arene-(fluoro)arene interactions, hydrogen bonding and crystal packing effects impact the molecular structures in the solid state and, ultimately, lead to very different packing arrangements.
- Kane, Christopher M.,Meyers, Tiffany B.,Yu, Xin,Gerken, Michael,Etzkorn, Markus
-
experimental part
p. 2969 - 2980
(2011/06/26)
-
- 1,3-Diynes synthesis by homo-coupling of terminal alkynes using a Pd(PPh3)4/Ag2O simple catalyst system
-
Amine- and copper salt-free palladium-catalyzed homo-coupling reaction of terminal alkynes proceeded efficiently in the presence of silver(I) oxide, which served as both activator and oxidant, in tetrahydrofuran at 60 °C to achieve satisfactory yields of 1,3-diyne compounds. It was demonstrated for the first time by means of XPS analysis that Pd(0) species can be oxidated to Pd(II) by silver(I) oxide.
- Feng, Xiujuan,Zhao, Ziran,Yang, Fan,Jin, Tienan,Ma, Yongjie,Bao, Ming
-
supporting information; experimental part
p. 1479 - 1482
(2011/05/09)
-
- CuI-catalyzed homocoupling of terminal alkynes to 1,3-diynes
-
A simple and efficient protocol for CuI-catalyzed oxidative homocoupling reaction of terminal alkynes to symmetrical 1,4-disubstituted 1,3-diynes was reported. The reaction can be carried out in the open air, using NaOAc as a base in the absence of any other additives. A variety of terminal alkynes were converted to the corresponding 1.3-diynes in good to excellent yields without any side product formation. Copyright
- Yin, Kun,Li, Chun-Ju,Li, Jian,Jia, Xue-Shun
-
experimental part
p. 16 - 20
(2011/09/16)
-
- A reusable CuSO4 · 5H2O/cationic 2,2′-bipyridyl system catalyzed homocoupling of terminal alkynes in water
-
A reusable CuSO4 · 5H2O/cationic 2,2′-bipyridyl system catalyzed the homocoupling reaction of terminal alkynes in water using I2 as the additive in the presence or absence of tetrabutylammonium bromide, giving the 1,3-diynes in good to high yields. After reaction, the residual aqueous solution could be reused several times.
- Wu, Tzu-Min,Huang, Shao-Hsien,Tsai, Fu-Yu
-
experimental part
p. 395 - 399
(2012/04/04)
-
- Homo and heterocoupling of terminal alkynes using catalytic CuCl 2 and DBU
-
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. CSIRO 2011.
- Balamurugan, Rengarajan,Naveen, Naganaboina,Manojveer, Seetharaman,Nama, Masthan Vali
-
experimental part
p. 567 - 575
(2012/01/02)
-
- Efficient copper(II) acetate catalyzed homo- and heterocoupling of terminal alkynes at ambient conditions
-
Symmetrical 1,3-diynes were obtained in quantitative yields using the copper(II) acetate catalyzed homocoupling of terminal alkynes in the presence of a stoichiometric amount of piperidine at 25 °C under aerobic conditions. We also accomplished facile syntheses of unsymmetric 1,3-diynes by heterocoupling terminal alkynes in very good yields under the reported reaction conditions. Georg Thieme Verlag Stuttgart.
- Balaraman, Kaluvu,Kesavan, Venkitasamy
-
experimental part
p. 3461 - 3466
(2010/11/21)
-
- An efficient approach to homocoupling of terminal alkynes: Solvent-free synthesis of 1,3-diynes using catalytic Cu(II) and base
-
We report an environmentally friendly, efficient method for transforming terminal acetylenes into 1,3-diynes based on catalytic amounts of a Cu(ii) salt and base under solvent-free conditions. The developed process conforms to the principles of 'green' chemistry and addresses the shortage of such methods for the synthesis of 1,3-diynes. The reaction is quite general and results in good yields. Interestingly, the system also allows the synthesis of unsymmetric 1,3-diynes by cross-coupling of two different terminal alkynes. Finally, the catalyst can also be recycled.
- Wang, Dong,Li, Jihui,Li, Na,Gao, Tingting,Hou, Sihua,Chen, Baohua
-
supporting information; experimental part
p. 45 - 48
(2010/05/17)
-
- Scope and reaction mechanism of an aerobic oxidative alkyne homocoupling catalyzed by a di-copper-substituted silicotungstate
-
The di-copper-substituted γ-Keggin-type silicotungstate TBA 4[γ-H2SiW10O36Cu 2(μ-1,1-N3)2] (I, TBA = tetra-n- butylammonium) could act as an efficient reusable homogeneous catalyst for the aerobic oxidative alkyne homocoupling. Various kinds of structurally diverse terminal alkynes including aromatic, heteroaromatic, aliphatic, double bond-containing, silylacetylene, propargylic alcohol, and propargylic amine derivatives could selectively be converted into the corresponding diynes in the presence of I. The catalytic activity of I was much higher than those of the mono-copper-substituted silicotungstate, monomeric copper complexes, and simple copper salts, showing that the di-copper core in I plays an important role in the present alkyne homocoupling. The reaction mechanism involving the formation of the di-copper(II)-alkynyl intermediate, reductive elimination of a diyne, and re-oxidation of reduced copper species by O2 has been proposed.
- Mizuno, Noritaka,Kamata, Keigo,Nakagawa, Yoshinao,Oishi, Takamichi,Yamaguchi, Kazuya
-
experimental part
p. 359 - 363
(2011/01/04)
-
- Alkynylcopper(i) polymers and their use in a mechanistic study of alkyne-azide click reactions
-
Polymeric dinuclear alkynylcopper(i) complexes, for example phenylethynylcopper(i), can be prepared by a robust method involving the interaction of terminal alkynes with copper(ii) salts in acetonitrile. The use of the ladder polymers provides heterogeneous catalysts for copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions and provides important mechanistic information.
- Buckley, Benjamin R.,Dann, Sandra E.,Harris, Daniel P.,Heaney, Harry,Stubbs, Emma C.
-
supporting information; experimental part
p. 2274 - 2276
(2010/07/08)
-
- Iron/copper promoted oxidative homo-coupling reaction of terminal alkynes using air as the oxidant
-
An inexpensive catalytic system, which used a readily available Fe(acac)3 and trace quantity of Cu(acac)2 as the co-catalyst and air as the oxidant for the homo-coupling of terminal alkynes, has been developed. The catalytic system could also apply to the cross-coupling reaction of two different terminal alkynes.
- Meng, Xu,Li, Chuanbin,Han, Baochun,Wang, Tiansheng,Chen, Baohua
-
supporting information; scheme or table
p. 4029 - 4031
(2010/07/06)
-
- Nickel-catalyzed oxidative coupling reactions of two different terminal alkynes using O2 as the oxidant at room temperature: Facile syntheses of unsymmetric 1,3-diynes
-
(Formula Presented) Two different terminal alkynes now can be coupled together in the presence of NiCl2-6H2O/Cul by using an excess of one of the terminal alkyne substrates. The new method employed 20 mol % TMEDA as the ligand and environmentally benign O2 or air as the oxidant. It is the first example using Ni-salt as catalyst by employing air or O2 as oxidant, which led to efficient heterocoupling of two different alkynes.
- Yin, Weiyan,He, Chuan,Chen, Mao,Zhang, Heng,Lei, Aiwen
-
supporting information; scheme or table
p. 709 - 712
(2009/08/12)
-
- A simple one-pot procedure for the direct homocoupling of terminal alkynes promoted by copper nanoparticles
-
The reaction of different terminal alkynes with readily prepared copper(O) nanoparticles led to the formation of the corresponding symmetrical 1,4-disubstituted 1,3-diynes in good yield. No palladium, ligands, or oxidant additives were needed. For aliphatic terminal alkynes, the use of sodium carbonate as base markedly improved the reaction rate and allowed the use of a substoichiometric amount of the copper nanoparticles.
- Nador, Fabiana,Fortunato, Leandro,Moglie, Yanina,Vitale, Cristian,Radivoy, Gabriel
-
experimental part
p. 4027 - 4031
(2010/03/26)
-
- Copper powder-mediated homocoupling reactions of iodoacetylenes to synthesize symmetrical 1,3-butadiynes
-
A new route to synthesize symmetrical 1,3-butadiynes from iodoacetylenes in the presence of copper powder and pyridine was developed. Moderate to excellent yields were obtained through an efficient and simple process involving the copper powder without any further activation. Copyright Taylor & Francis Group, LLC.
- Xue, Song,Meng, Ling-Guo,Guo, Qing-Xiang
-
p. 2243 - 2251
(2008/09/21)
-
- CuI/iodine-mediated homocoupling reaction of terminal alkynes to 1,3-diynes
-
A facile and efficient pathway for CuI/iodine-mediated homocoupling reaction of terminal alkynes to symmetrical 1,4-disubstituted 1,3-diynes in good to excellent yields was reported.
- Li, Dafeng,Yin, Kun,Li, Jian,Jia, Xueshun
-
body text
p. 5918 - 5919
(2009/04/05)
-
- New irreversible thermochromic polydiacetylenes
-
New diacetylenic compounds are described. These compounds are unfunctionalised, monoalcohols, diols or monoesters and present irreversible thermochromic behaviour. When heated, these diynes change colour from blue to red in temperature ranging between -50 and +75 °C depending on chain lengths. A relationship between the number of atoms and the thermochromism temperature has been highlighted. Moreover, a mechanism of this thermochromic phenomenon is demonstrated based on Raman spectroscopy, ESR and solid NMR.
- Rougeau, Laurent,Picq, Dominique,Rastello, Marie,Frantz, Yves
-
p. 9430 - 9436
(2008/12/22)
-
- Efficient oxidative alkyne homocoupling catalyzed by a monomeric dicopper-substituted silicotungstate
-
(Chemical Equation Presented) It goes on the dicopper core! A monomeric γ-Keggin silicotungstate with a dicopper core that is bridged by two μ-1,1-azido ligands catalyzes oxidative alkyne homocoupling reactions whereby various kinds of aromatic and aliphatic alkynes are selectively converted into the corresponding diynes (see picture).
- Kamata, Keigo,Yamaguchi, Syuhei,Kotani, Miyuki,Yamaguchi, Kazuya,Mizuno, Noritaka
-
p. 2407 - 2410
(2008/12/23)
-
- Synthesis and structural characterization of a monomeric di-copper-substituted silicotungstate [γ-H2SiW10O36Cu2(μ-1,1-N3)2]4- and the catalysis of oxidative homocoupling of alkynes
-
The di-copper-substituted γ-Keggin silicotungstate with bis-μ-1,1-azido ligands TBA4[γ-H2SiW10O36Cu2(μ-1,1-N3)2] (1, TBA = tetra-n-butylammonium) was synthesized in an aqueous medium. The crystal structure of the anion part of 1 was a monomer of the basal-basal end-on diazido-bridged di-copper-substituted γ-Keggin silicotungstate. The NMR and CSI-MS spectra of 1 in organic solvents, such as acetonitrile, benzonitrile, and 1,2-dichloroethane, showed that complex 1 was present as a monomer of the di-copper-substituted γ-Keggin silicotungstate. Complex 1 could act as an effective homogeneous catalyst for the oxidative homocoupling of various types of alkynes, including aromatic, aliphatic, and heteroatom-containing ones. The reaction possibly proceeds as follows: First, the ligand exchange proceeds between the azido groups in 1 and alkynyl groups to form the corresponding diyne with the reduced copper(I) species via the di-copper(II)-alkynyl intermediate, then the reduced species is reoxidized by molecular oxygen, and the oxidized species reacts with an alkyne to regenerate the alkynyl intermediate.
- Yamaguchi, Kazuya,Kamata, Keigo,Yamaguchi, Syuhei,Kotani, Miyuki,Mizuno, Noritaka
-
scheme or table
p. 121 - 130
(2009/02/08)
-
- Selectivity in the Ruthenium-catalyzed Alder ene reactions of di- and triynes
-
Ruthenium-catalyzed Alder ene reactions between diynes and triynes with terminal alkenes gave the corresponding enynes and enediynes with high regio- and site-selectivity. The selectivity profile clearly indicates that one of the alkynyl moieties of 1,3-diynes not participating in the reaction determines the regiochemistry, whereas the interplay between steric hindrance and polar substituents at the propargylic sites determines the site-selectivity. Copyright
- Eun, Jin Cho,Lee, Daesung
-
p. 6692 - 6693
(2008/02/04)
-
- Efficient and recyclable reaction system for the homocoupling of terminal acetylenes
-
Diynes were synthesized in high yields by homocoupling of terminal arylacetylenes and terminal alkylacetylenes in Cu(OAc)2-PEG (polyethyleneglycol) with NaOAc as a base. Cu(OAc)2-PEG was readily recycled via solvent precipitation with efficient recyclability. Copyright Taylor & Francis Group, LLC.
- Lu, Xiaoling,Zhang, Yuhong,Luo, Chengcai,Wang, Yanguang
-
p. 2503 - 2511
(2007/10/03)
-
- Cu(II)-promoted oxidative homocoupling reaction of terminal alkynes in supercritical carbon dioxide
-
Oxidative homocoupling reaction of various terminal alkynes in supercritical carbon dioxide (scCO2) has been reported. The final optimized reaction conditions for the reaction in ScCO2 were determined to be cupric chloride (2 mmol), sodium acetate (2 mmol), methanol (1 mL) and CO2 (14 MPa) at 40 °C. Sodium acetate was superior to pyridine in the present reaction system. Methanol, as a co-solvent of ScCO 2, was necessary to help dissolve the inorganic salt and facilitated the reaction. Higher solubility of cupric chloride in the scCO 2-methanol medium than other cupric salts, e.g. CuSO4, Cu(NO3)2, Cu(OAc)2 and cupric bromide, guaranteed its high catalytic ability. Variations of the pressure of ScCO 2 and temperature in a certain range have almost little impact on the reaction efficiency. A mechanism involving copper(II)-acetylide complex was supposed in which AcO- or Cl- instead of N-containing compounds acted as ligands. The reaction system in ScCO2 is an effective and environmental-friendly alternative to the previous methods of homocoupling of terminal alkynes involving volatile organic compounds. Georg Thieme Verlag Stuttgart.
- Jiang, Huan-Feng,Tang, Jin-Yu,Wang, A.-Zhong,Deng, Guo-Hua,Yang, Shao-Rong
-
p. 1155 - 1161
(2007/10/03)
-
- The effects of amines on oxidative homo-coupling of terminal alkynes promoted by copper salts
-
The effects of all kinds of amines on homo-couplings (Glaser reactions) of terminal alkynes promoted by copper salts and the Sonogashira coupling reactions were studied systematically. Diethylamine (2° amine) can serve as an excellent solvent, base and coordination ligand in the oxidative homo-coupling of terminal alkynes and several modified Glaser coupling procedures have been developed which are based on a catalytic amount of cuprous salts (Cul, CuBr or CuCl) with diethylamine systems. Homo-coupling of terminal acetylenes in the Sonogashira reaction could be inhibited by using triethylamine (3° amine) as reaction medium, and the cross-coupling products were formed as the exclusive products.
- Wang, Lei,Yan, Jincan,Li, Pinhua,Wang, Min,Su, Caina
-
p. 112 - 115
(2007/10/03)
-
- NOVEL SYNTHETIC BINDING PAIRS AND USES THEREOF
-
Cucurbituril assemblies, polyamine structures capable of binding thereto, affinity pairs of cucurbituril assemblies and such polyamine structures and methods utilizing same are disclosed.
- -
-
Page/Page column 63
(2010/02/11)
-
- DIACETYLENIC MATERIALS FOR SENSING APPLICATIONS
-
Diacetylenic materials for the colorimetric detection of an analyte or exposure to certain environmental factors are disclosed as well as the polymerization reaction products of these diacetylenic compounds.
- -
-
Page/Page column 23
(2010/02/07)
-
- Pd-catalysed cross coupling of terminal alkynes to diynes in the absence of a stoichiometic additive
-
An efficient, room temperature procedure for the cross-coupling of a range of terminal alkynes, using standard Sonogashira cross-coupling conditions (Pd/Cu) is presented. At higher reaction temperatures, head-to-tail or head-to-head dimerisation affords 1,3- and 1,4-disubstituted enynes, respectively as minor products.
- Fairlamb, Ian J. S.,Baeuerlein, Patrick S.,Marrison, Lester R.,Dickinson, Julia M.
-
p. 632 - 633
(2007/10/03)
-
- Transmetalation of palladium enolate and its application in palladium-catalyzed homocoupling of alkynes: A room-temperature, highly efficient route to make diynes
-
A novel pathway for the homocoupling reaction has been achieved using a similar protocol as the cross-coupling reaction. Ethyl bromoacetate is chosen to initiate the coupling reaction through oxidatlve addition to a Pd(0) species, and an PdBr(enolate) intermediate is formed. This intermediate can undergo double transmetalation with an alkynyl copper reagent, and reductive elimination produces a variety of diynes in high yields.
- Lei, Aiwen,Srivastava, Manisha,Zhang, Xumu
-
p. 1969 - 1971
(2007/10/03)
-
- Regioselective palladium-catalyzed cross-coupling reactions in the synthesis of novel 2,3-disubstituted thiophene derivatives
-
A reactivity optimization study of the palladium-catalyzed cross-coupling reactions of 2,3-dibromothiophene and organometallic reagents has been conducted. Regioselective coupling at the C2 position, accomplished most notably by Suzuki coupling, was combined with a Stille reaction at C3 using Fu's modification, to afford the 2,3-disubstituted thiophene derivatives.
- Pereira, Raquel,Iglesias, Beatriz,De Lera, Angel R
-
p. 7871 - 7881
(2007/10/03)
-
- Synthesis and cytotoxic activity of a series of diacetylenic compounds related to falcarindiol
-
The synthesis of a series of diacetylenic compounds related to the natural product falcarindiol has been carried out. Unsymmetrical diacetylenes were prepared by a modification of the Cadiot-Chodkiewicz coupling reaction, while a Glaser coupling was used to prepare symmetrical diacetylenes. These compounds have been tested for in vitro cytotoxic activity against Hep-G2, and H-4-II-E cell lines. Diacetylenes with additional unsaturation at C-1, 2, appended with hydroxyl groups at C-3 and C-8, or with long hydrophobic chains, exhibited IC50 values in the micromolar range.
- Setzer,Gu,Wells,Setzer,Moriarity
-
p. 1776 - 1777
(2007/10/03)
-