- In the optically-multiplexed-
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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.
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Paragraph 0216; 0217
(2020/12/30)
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- Palladium-Catalyzed Aerobic Homocoupling of Alkynes: Full Mechanistic Characterization of a More Complex Oxidase-Type Behavior
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A combined experimental and computational approach has been used to shed light on the mechanism of the Pd-catalyzed oxidative homocoupling of alkynes using oxygen as the oxidant. Mechanistic understanding is important because of the synthetically relevant direct involvement of oxygen in the oxidative coupling and because of the presence of related processes as undesired side reactions in cross-coupling reactions involving terminal alkynes. A low-ligated [Pd(PPh3)(alkyne)] complex is key in the process, and it can be conveniently generated from allylic palladium(II) complexes in the presence of a base or from Pd(I) allylic dimers as precatalysts. The catalytic coupling occurs by alkyne metalation to give an anionic [Pd(PPh3)(alkynyl)]- complex that is then oxidized by oxygen. The interaction with oxygen occurs only on this electron-rich Pd(0) anionic species and leads to a (κO,κO-peroxo)palladium(II) singlet intermediate that undergoes subsequent protonolysis to give a (κO-hydroperoxo)palladium(II) complex and then hydrogen peroxide. The second alkyne metalation occurs on a Pd(II) derivative to give a bis(alkynyl)palladium(II) complex that evolves to the product by reductive elimination as the product-forming step. This reaction is an oxidase-type process that, in contrast to most Pd-catalyzed oxidative processes, occurs without separation of the substrate transformation and the catalyst oxidation, with these two processes being intertwined and dependent on one another.
- Toledo, Alberto,Funes-Ardoiz, Ignacio,Maseras, Feliu,Albéniz, Ana C.
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p. 7495 - 7506
(2018/07/21)
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- Good conductivity of a single component polydiacetylene film
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Two films were prepared from single component monomer solutions. In these monomers, diacetylene and two acid groups are licked by flexible side chains. The side chain serves as the spacer between diacetylenes. After UV-irradiation, monomer films were transformed to polydiacetylene films and one of films exhibited conductivity drastically increases. This conductivity is two orders of magnitude greater than the conductivity value of reported nondoped polydiacetylene films.
- Tang, Zhenyu,Li, Ming,Song, Mengyao,Jiang, Li,Li, Jinhua,He, Yunbin,Zhou, Lixin
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p. 174 - 178
(2017/07/03)
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- Cobalt Catalyzed, Regioselective C(sp2)-H Activation of Amides with 1,3-Diynes
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The development of a first row transition metal (cobalt)-based catalyst for the as yet unexplored C-H activation-driven reaction of 1,3-diynes, themselves a functional class of interest in a range of application areas, to form isoquinolinones - an importa
- Kathiravan, Subban,Nicholls, Ian A.
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supporting information
p. 4758 - 4761
(2017/09/23)
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- Copper(i) chloride catalysed room temperature Csp-Csp homocoupling of terminal alkynes mediated by visible light
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We developed a technique mediated by visible light for the aerobic homocoupling of terminal alkynes to synthesize 1,3-conjugated diynes using a copper(i) chloride catalyst at room temperature. Compared with previously reported thermal processes, this photochemical method is simple, uses only mild reaction conditions, produces high yields and works well for substrates with electron-withdrawing groups without the need for bases/ligands, oxidants or palladium catalysts.
- Sagadevan, Arunachalam,Charpe, Vaibhav Pramod,Hwang, Kuo Chu
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p. 7688 - 7692
(2016/11/06)
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- Oxidative homocoupling of terminal alkynes under palladium-, ligand- and base-free conditions using Cu(II)-clay as a heterogeneous catalyst
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Homocoupling of terminal alkynes to 1,3-diynes has been investigated with Cu(II)-modified clay under mild and operationally simple conditions without the use of any ligand or a stabilizing agent. The catalyst is robust, ecofriendly, efficient, furnishes g
- Dar, Bashir Ahmad,Vyas, Dushyant,Shrivastava, Varsha,Farooq, Saleem,Sharma, Amit,Sharma, Sadhana,Sharma, Parduman R.,Sharma, Meena,Singh, Baldev
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p. 316 - 323
(2014/04/17)
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- Palladium(II)-copper(I) mediated homotrimerization and homotetramerization of terminal alkynes
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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
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supporting information
p. 1883 - 1885
(2014/03/21)
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- Efficient copper(II) acetate catalyzed homo- and heterocoupling of terminal alkynes at ambient conditions
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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
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experimental part
p. 3461 - 3466
(2010/11/21)
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- Synthesis, kinase inhibitory potencies and in vitro antiproliferative activity of isoindigo and 7′-azaisoindigo derivatives substituted by Sonogashira cross-coupling
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In the course of structure-activity relationship studies we were interested in the synthesis of isoindigo and 7′-azaisoindigo derivatives substituted at the N-1 position by a 1-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl), at the 5′-position by various cha
- Bouchikhi, Fadoua,Anizon, Fabrice,Moreau, Pascale
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experimental part
p. 2705 - 2710
(2009/10/02)
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- New irreversible thermochromic polydiacetylenes
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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
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p. 9430 - 9436
(2008/12/22)
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- Synthesis of 1-aryl-1,3-diyne and 2-aryl-1,1-dialkynylethene from the Sonogashira reactions of 2-aryl-1,1-dibromoethene
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Both 1-aryl-1,3-diyne and 2-aryl-1,1-dialkynylethene were produced from the Sonogashira reactions of 2-aryl-1,1-dibromoethene with 1-alkyne. The ratio of the products varied according to the reaction conditions. The coupling reactions in benzene afforded
- Lee, Hee Bong,Huh, Dal Ho,Oh, Joon Seok,Min, Gwan-Hong,Kim, Byung Hyun,Lee, Dong Hwal,Hwang, Jae Kwang,Kim, Young Gyu
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p. 8283 - 8290
(2007/10/03)
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- Regioselective palladium-catalyzed cross-coupling reactions in the synthesis of novel 2,3-disubstituted thiophene derivatives
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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
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p. 7871 - 7881
(2007/10/03)
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