- Solid-state self-inclusion: The missing link
-
Molecular cannibalism: The concept of self-inclusion in the solid state can be subjective. A host-guest system is prepared in which the same compound (2,7-dimethyl-octa-3,5-diyne-2,7-diol) unequivocally plays both roles simultaneously. (Figure Presented).
- Lloyd, Gareth O.,Alen, Jo,Bredenkamp, Martin W.,De Vries, Elise J. C.,Esterhuysen, Catharine,Barbour, Leonard J.
-
-
Read Online
- Asymmetric synthesis of C2-symmetric axially chiral biaryls through rhodium-catalyzed and alkyne-controlled diastereoselective double [2+2+2] cycloaddition
-
The asymmetric synthesis of C2-symmetric axially chiral biaryls was achieved by the cationic rhodium(I)/1,3-bis(diphenylphosphino)propane (dppp) complex catalyzed diastereoselective double [2+2+2] cycloaddition of (R)-3-butyn-2-ol-derived tetraynes with functionalized monoynes. Interestingly, the use of propiolates afforded biaryls possessing large dihedral angles, and in contrast, the use of propargyl alcohol afforded biaryls possessing small dihedral angles. A cationic rhodium(I)/1,3-bis(diphenylphosphino)propane (dppp) complex catalyzed double [2+2+2] cycloaddition of (R)-3-butyn-2-ol-derived tetraynes with functionalized monoynes affords C2-symmetric axially chiral biaryls with complete diastereoselectivity. The use of propiolates affords biaryls possessing large dihedral angles, and in contrast, the use of propargyl alcohol affords biaryls possessing small dihedral angles. nbd = norbornadiene. Copyright
- Mori, Ayaka,Araki, Tatsuya,Miyauchi, Yuta,Noguchi, Keiichi,Tanaka, Ken
-
-
Read Online
- In Situ Synthesis of CuN4/Mesoporous N-Doped Carbon for Selective Oxidative Crosscoupling of Terminal Alkynes under Mild Conditions
-
The 1,3-conjugated diynes are an important class of chemical intermediates, and the selective crosscoupling of terminal alkynes is an efficient chemical process for manufacturing asymmetrical 1,3-conjugated diynes. However, it often occurs in homogenous conditions and costs a lot for reaction treatment. Herein, a copper catalyzed strategy is used to synthesize highly ordered mesoporous nitrogen-doped carbon material (OMNC), and the copper species is in situ transformed into the copper single-atom site with four nitrogen coordination (CuN4). These features make the CuN4/OMNC catalyst efficient for selective oxidative crosscoupling of terminal alkynes, and a wide range of asymmetrical and symmetrical 1,3-diynes (26 examples) under mild conditions (40?°C) and low substrates ratio (1.3). Density functional theory (DFT) calculations reveal that the aryl–alkyl crosscoupling has the lowest energy barrier on the CuN4 site, which can explain the high selectivity. In addition, the catalyst can be separated and reused by simply centrifugation or filtration. This work can open a facile avenue for constructing single-atom loaded mesoporous materials to bridge homogeneous and heterogeneous catalysis.
- Cao, Yue,Gu, Dong,Lei, Aiwen,Liang, Zhenjin,Su, Yaqiong,Wu, Jinsong,Wu, Yong,Xiao, Wei,Yang, Dali,Yu, Ruohan,Zhang, Dongchao,Zhang, Yuanteng
-
-
- Preparation method of water-soluble vitamin E participated conjugated diyne compound
-
The water-soluble vitamin E participates in the green preparation method of the conjugated diyne compound, the water serves as a reaction solvent, the use amount of the organic solvent is reduced, and zero emission of the solvent is realized. The excellent physicochemical properties of water are fully utilized, the reaction conditions are mild and efficient, the surfactant TPGS - 750 - M can be recycled through treatment, and the principle of environmental friendliness is completely met. The reaction substrate is wide in applicability, can catalyze the aryl alkyne, can catalyze the aliphatic hydrocarbon, and provides a simple and environment-friendly preparation method for the synthesis of the conjugated diyne. The copper catalyst which is more suitable for the reaction and reaction medium of the invention is screened out, and the yield is greatly improved.
- -
-
Paragraph 0137-0141
(2021/11/14)
-
- Strategy to isolate ionic gold sites on silica surface: Increasing their efficiency as catalyst for the formation of 1,3-diynes
-
A new strategy is presented to obtain an efficient heterogeneous gold catalyst constituted by isolated ionic gold sites, which is known to be effective in alkyne coupling reaction. The procedure is based on a significant difference between offered gold amount and available adsorbent sites on the support, ensuring the formation of very active isolated gold ion sites. In order to achieve this purpose, mesoporous silica xerogel was grafted with an ionic silsesquioxane containing charged ammonium quaternary group. The modified silica showed 0.25 mmol of cationic sites per gram of material and presented thermal stability up to 200 °C. This material was applied as support for immobilization of Au(III) ions as square planar AuCl4? complex. The gold amount offered was just 12 % of the exchangeable capacity. The catalyst was efficiently applied in the cross coupling reactions, in which only 0.22 mol% was applied to obtain symmetric and non-symmetric 1,3-diynes.
- Didó, Cezar A.,Coelho, Felipe L.,Closs, Maurício B.,Deon, Monique,Horowitz, Flavio,Bernardi, Fabiano,Schneider, Paulo H.,Benvenutti, Edilson V.
-
-
- Tuning of cross-Glaser products mediated by substrate-catalyst polymeric backbone interactions
-
Tuning of cross-Glaser products using different polymeric backbones supported by copper oxide nano-catalysts has been demonstrated by tweaking the substrate-catalyst interactions under greener conditions. Further, highly reactive magnetically separable and recyclable catalyst with scalability is demonstrated.
- Ali, Md. Ehesan,Dar, Arif Hassan,Gowri, Vijayendran,Jayamurugan, Govindasamy,Kaur, Sharanjeet,Mukhopadhyaya, Aritra,Neethu, K. M.,Sartaliya, Shaifali,Selim, Abdul
-
supporting information
p. 2582 - 2585
(2020/03/10)
-
- SUBSTITUTED IMIDAZOLECARBOXYLATE DERIVATIVES AND THE USE THEREOF
-
A compound is shown in formula (I). The derivatives of the compound include a stereoisomer, a pharmaceutically acceptable salt, a solvate, a prodrug, a metabolite, a deuterated derivative. The compound is a structurally novel substituted imidazole formate derivative. Substituted imidazole formate derivatives are used in preparing a drug with sedative, hypnotic and/or anesthetic effects, as well as a drug that can control the state of epilepsy. The compound has a good inhibitory effect on the central nervous system, and provides a new option for clinical screening of and/or preparation of a drug with sedative, hypnotic and/or anesthetic effects and controlling the state of epilepsy.
- -
-
Paragraph 0912-0914
(2020/12/08)
-
- Copper Nanoparticles on Ordered Mesoporous Carbon Nitride Support: a Superior Catalyst for Homo- and Cross-Coupling of Terminal Alkynes under Base-Free Conditions
-
A novel ordered mesoporous carbon nitride (OMCN) was synthesized as a functionalized support with 2,4,6-trichloro-1,3,5-triazine and benzidine as starting materials in the presence of SBA-15 as a template. Copper nanoparticles were then loaded on the C–N material to achieve a novel nanocomposite catalyst (Cu NPs-OMCN). The nanocomposite was utilized as a highly efficient catalyst for homo- and cross-coupling of terminal alkynes under base-free conditions in ethanol, and various symmetrical and unsymmetrical 1,3-diynes were obtained with good to excellent yields. Moreover, based on this reaction, a one-pot approach to synthesize 2,5-disubstituted thiophenes and furans from terminal alkynes were developed. Furthermore, the heterogeneous catalyst could be recovered and reused conveniently for several times with satisfactory yields.
- Xu, Hang,Wu, Liangying,Tian, Jing,Wang, Jun,Wang, Peng,Niu, Xiyu,Yao, Xiaoquan
-
p. 6690 - 6696
(2019/11/02)
-
- Metallomicelle catalyzed aerobic tandem desilylation/Glaser reaction in water
-
PEG-grafted nitrogen ligands were synthesized. The corresponding copper complexes serve as metallomicellar nanoreactors for the aerobic tandem desilylation/Glaser coupling of TMS-protected alkynes in water. The protocol is also suitable for base-free homocoupling of terminal alkynes. The metallomicellar catalyst could be recycled 5 times with minor loss of reactivity.
- Tang, Shanyu,Li, Longjia,Ren, Xuanhe,Li, Jiao,Yang, Guanyu,Li, Heng,Yuan, Bingxin
-
supporting information
p. 2899 - 2904
(2019/06/17)
-
- Gold-Catalyzed Oxidative Coupling of Alkynes toward the Synthesis of Cyclic Conjugated Diynes
-
Gold-catalyzed oxidative coupling of alkynes was developed as an efficient approach for the synthesis of challenging cyclic conjugated diynes (CCD). Compared with the classic copper-promoted oxidative coupling reaction of alkynes, this gold-catalyzed process exhibited a faster reaction rate due to rapid reductive elimination from the Au(III) intermediate. This unique reactivity thus allowed a challenging diyne macrocyclization to take place with high efficiency. Condition screening revealed an [(n-Bu)4N]+[Cl-Au-Cl]? salt as the optimal pre-catalyst. Macrocycles with ring size between 13 and 28 atoms were prepared in moderate to good yields, which highlighted the broad substrate scope of this new strategy. Furthermore, the synthetic utilities of the CCDs for copper-free click chemistry have been demonstrated, showcasing the potential application of this strategy in biological systems. Macrocycles are important structural moieties in medicinal and biological research, and efficient methods for macrocyclization are always in high demand. With the unique conformation having six carbon atoms in a linear geometry, the cyclic conjugated diynes (CCD) present greater synthetic challenges and have been much less explored. Therefore, application of these unique macrocycles in biological studies is largely unexplored. Here, we describe the discovery of gold-catalyzed Glaser-Hay type oxidative coupling of terminal alkynes to achieve CCD under diluted conditions with broad substrate scope and great functional group compatibility. Taking advantage of the 14-member cyclic diyne, a copper-free click chemistry was achieved, which provided an effective alternative strategy for the traditional cyclooctyne-based azide-alkyne cycloaddition, suggesting a promising future for this method in tackling challenging problems in related biological and medicinal research. Gold-catalyzed oxidative coupling of alkynes was developed as an efficient approach for the synthesis of challenging cyclic conjugated diyne. Compared with copper-promoted oxidative coupling, this protocol allowed macrocyclization under dilute conditions with good overall reactivity and high functional group tolerance. The success in achieving copper-free click chemistry on cyclic conjugated diyne highlights its potential application in biological and medicinal research.
- Ye, Xiaohan,Peng, Haihui,Wei, Chiyu,Yuan, Teng,Wojtas, Lukasz,Shi, Xiaodong
-
supporting information
p. 1983 - 1993
(2018/10/02)
-
- Recyclable Cu/C3N4 composite catalysed homo- and cross-coupling of terminal alkynes under mild conditions
-
A Cu/C3N4 composite was prepared and utilized as a highly efficient and environmentally friendly catalyst for the homo- & cross-coupling of terminal alkynes. Excellent functional group tolerance and good yields were observed with oxygen as an oxidant in an isopropanol solution (or as additive) under ambient conditions. Furthermore, the composite catalyst shows good recyclability and can be recovered simply and reused several times without significant loss in its catalytic activities.
- Xu, Hang,Wu, Keying,Tian, Jing,Zhu, Li,Yao, Xiaoquan
-
supporting information
p. 793 - 797
(2018/03/02)
-
- Method for synthesizing 1,3-butadiyne compound by catalyzing molecular oxygen to oxidize water phase by water-soluble transition metal complex
-
The invention provides a method for synthesizing a 1,3-butadiyne compound by catalyzing molecular oxygen to oxidize a water phase by a water-soluble transition metal complex. A water-soluble metal complex formed by complexing a transition metal and a water-soluble ligand is a catalyst; in an oxygen or air environment, an alkynyl silanes compound or a terminated alkynes compound reacts in an alkaline water phase to generate the 1,3-butadiyne compound; and the reaction pressure is 0.01 to 0.5 MPa, the reaction temperature is 40 to 100 DEG C, and the reaction time is 4 to 24 hours. According to the method provided by the invention, the synthesis step is simple, the reaction conditions are mild, the operation is simple, convenient and feasible, and the product yield is 99 percent; furthermore,the method is applicable to a wide range of substrates, and a new concept is provided for synthesis of the conjugated 1,3-butadiyne compound; the reaction is performed in the water phase without adding other organic solvents; and the catalyst is high in catalysis activity and high in reaction efficiency, can be used for multiple times, produces a small number of products, and has a relatively good industrial application prospect.
- -
-
Paragraph 0058; 0059; 0060; 0061
(2018/09/13)
-
- New non-protienogenic fluorescent amino acids: Benzoxazol-5-yl-alanine derivatives containing acetylene unit. Synthesis, spectral and photophysical properties
-
New derivatives of non-proteinogenic amino acids benzoxazol-5-yl-alanine containing substituted acetylene derivative were synthesized according to Sonogashira coupling reaction. All of the obtained compounds are fluorescent. They are characterized by high or moderate molar absorption coefficients, large Stokes shifts, high fluorescence quantum yields and very high brightness. All of these parameters as well as the positions of absorption and emission bands depend on the type and size of substituent and the solvent polarity. Their high brightness enables working with low concentrations, simple and easy detection of spectral absorption and fluorescence analyzes. Moreover, amino acid part of studied compounds allow to use them as covalently attached to a peptide or protein fluorescent probes in biological system studies.
- Bylińska, Irena,Guzow, Katarzyna,Wójcik, Justyna,Wiczk, Wies?aw
-
p. 679 - 685
(2018/07/14)
-
- Copper(II)/Palladium(II) catalysed highly selective cross-coupling of terminal alkynes in supercritical carbon dioxide
-
An efficient protocol for the synthesis of unsymmetrical 1,3-diynes was developed using supercritical carbon dioxide (ScCO2) as the solvent. The direct coupling of two different terminal alkynes is catalysed by a bimetallic catalyst, CuCl2·2H2O/Pd(NH3)4Cl2·H2O, in the presence of the base tetramethylethylenediamine (TMEDA) and O2. In pure ScCO2, our bimetallic catalytic system maintains high activity over a wide substrate scope to provide unsymmetrical 1,3-diynes in good to excellent yields. In the proposed reaction mechanism, the synergistic cooperation between copper(II) and palladium(II) centres is responsible for the superior selectivity of the cross-coupling.
- Wang, Yunlong,Suo, Quanling,Han, Limin,Guo, Linlin,Wang, Yaqi,Li, Fawang
-
p. 1918 - 1925
(2018/03/12)
-
- Anchoring Triazole-Gold(I) Complex into Porous Organic Polymer to Boost the Stability and Reactivity of Gold(I) Catalyst
-
Stability and reactivity have been recognized as some critical issues for gold(I) catalysts. Such issues can be well-circumvented by anchoring the gold(I) complex onto the backbones of porous organic polymer (POP) followed by coordination with a triazole ligand as illustrated in the present work via a series of gold(I)-catalyzed reactions. In this strategy, 1,2,3-triazole was used as the special "X-factor" to avoid the formation of solid AgCl involved in typical gold-activation processes. The catalyst could be readily recycled without loss of reactivity. Moreover, compared with the PPh3-modified polystyrene beads, the POP support was advantageous by providing high surface area, hierarchical porosity, and better stabilization of cations. In some cases, significantly improved reactivity was observed, even more so than using the homogeneous system, which further highlighted the great potential of this heterogeneous gold catalyst.
- Cai, Rong,Ye, Xiaohan,Sun, Qi,He, Qiuqin,He, Ying,Ma, Shengqian,Shi, Xiaodong
-
p. 1087 - 1092
(2017/08/09)
-
- Phosphorus-Containing Bis-allenes: Synthesis and Heterocyclization Reactions Mediated by Iodine or Copper Dibromide
-
Bisphosphorylallenes were easily obtained in multigram scale from the Wittig-type rearrangement of bispropargyl alcohols. Unlike other conjugated bis-allenes, these reagents underwent a double cyclization mediated by iodine or copper dibromide leading to the formation of bis-1,2-oxaphospholenes.
- Essid,Laborde,Legros,Sevrain,Touil,Rolland,Ayad,Volle,Pirat,Virieux
-
supporting information
p. 1882 - 1885
(2017/04/11)
-
- Application of the polyacrylonitrile fiber as a novel support for polymer-supported copper catalysts in terminal alkyne homocoupling reactions
-
A commercially available synthetic polyacrylonitrile fiber, capable of acting as a novel support for polymer-supported copper catalyst in terminal alkyne homocoupling reactions, is presented. Detailed characterization by inductively coupled plasma (ICP) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) confirmed the changes and stability of the fiber catalyst during the modification and utilization processes. Moreover, the catalytic reactions proceeded at room temperature using air as a green oxidant to afford nearly quantitative yields (95-99%); the fiber catalyst has shown excellent activity and superior recyclability (over 16 cycles); and the procedure is operationally simple and amenable to the gram scale in continuous-flow processing. Furthermore, the prominent features (high strength, good flexibility, etc.) of the polyacrylonitrile fiber make the fiber-supported catalyst very attractive for fixed-bed reactors in the chemical industry.
- Shi, Xian-Lei,Hu, Qianqian,Wang, Fang,Zhang, Wenqin,Duan, Peigao
-
p. 233 - 239
(2016/03/08)
-
- Ionic liquid-promoted Copper(II)-Catalyzed homocoupling of terminal alkynes in aqueous phase or under solvent-limited conditions
-
A reusable ionic liquid 1-butyl-3-methylimidazolium bromide/Cu(II) system was proven to be a reusable catalyst for the homocoupling of terminal alkynes at mild temperature using air as oxidant in aqueous phase or under solvent-limited conditions. In most cases, good to excellent yields can be achieved, either aromatic alkynes or aliphatic alkynes were used as substrates. The homocoupling products 1,3-diynes were separated by extraction from the reaction system. And the activity of residue showed it could be reused for 3 and 6 cycles respectively under the aqueous phase conditions and solventlimited conditions. Furthermore, this reaction can be easily scaled up to gram level.
- Li, Shiguang,Chen, Xi,Chen, Jinping,Gong, Hang
-
supporting information
p. 794 - 797
(2016/08/02)
-
- Copper(i) chloride catalysed room temperature Csp-Csp homocoupling of terminal alkynes mediated by visible light
-
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
-
p. 7688 - 7692
(2016/11/06)
-
- Copper Catalysis for Selective Heterocoupling of Terminal Alkynes
-
A Cu-catalyzed selective aerobic heterocoupling of terminal alkynes is disclosed, which enables the synthesis of a broad range of unsymmetrical 1,3-diynes in good to excellent yields. The results disprove the long-held belief that homocouplings are exclusively favored in the Glaser-Hay reaction.
- Su, Lebin,Dong, Jianyu,Liu, Long,Sun, Mengli,Qiu, Renhua,Zhou, Yongbo,Yin, Shuang-Feng
-
supporting information
p. 12348 - 12351
(2016/10/07)
-
- 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)
-
- Ligand-Assisted Gold-Catalyzed Cross-Coupling with Aryldiazonium Salts: Redox Gold Catalysis without an External Oxidant
-
Gold-catalyzed C(sp)-C(sp2) and C(sp2)-C(sp2) cross-coupling reactions are accomplished with aryldiazonium salts as the coupling partner. With the assistance of bpy ligand, gold(I) species were oxidized to gold(III) by diazonium without any external oxidants. Monitoring the reaction with NMR and ESI-MS provided strong evidence for the nitrogen extrusion followed by AuIII reductive elimination as the key step.
- Cai, Rong,Lu, Mei,Aguilera, Ellen Y.,Xi, Yumeng,Akhmedov, Novruz G.,Petersen, Jeffrey L.,Chen, Hao,Shi, Xiaodong
-
supporting information
p. 8772 - 8776
(2015/11/27)
-
- A mild CuI-catalyzed Glaser-type homo-coupling reaction using α,α-dibromo-β-dicarbonyl compounds as oxidants
-
Exploration of α,α-dibromo-β-dicarbonyl compounds as novel organic oxidants for the mild Cu(I)-catalyzed Glaser-type homo-coupling reaction has been achieved, which provides an alternatively efficient pathway for the construction of 1,3-conjugated structures. In addition, the mechanism of this reaction was investigated.
- Fan, Xiaohui,Li, Na,Shen, Tong,Cui, Xiao-Meng,Lv, Hao,Zhu, Hong-Bo,Guan, Yong-Hong
-
supporting information
p. 256 - 261
(2014/01/06)
-
- Cu-modified hydroxy-apatite as catalyst for Glaser-Hay CC homo- coupling reaction of terminal alkynes
-
The oxidative Glaser-Hay coupling reaction of terminal alkynes is a very important reaction in organic chemistry to achieve the synthesis of diyne compounds. In general the reaction is performed under homogeneous conditions using Cu(I) or Cu(II) salts in the presence of a reagent such as tetramethylethylenediamine (TMEDA), which can bind to copper ions, an organic base and dioxygen. Although this reaction is known for a long time, the mechanism is still under discussion. Pursuing our investigations on the use of apatites as catalysts for organic reactions we highlight in this work how it is possible to catalyze the Glaser-Hay reaction under heterogeneous conditions using a Cu-modified hydroxyapatite (Cu-HAp). With several para-substituted phenyl-acetylenes and alkynols we show that Cu-HAp acts as catalyst for CC coupling reactions leading to diyne derivatives in high yields without using auxiliary chelating molecules and organic bases. These heterogeneous conditions allow an easy recovery of the catalyst and simplify the purification work-up.
- Maaten, Birgit,Moussa, Jamal,Desmarets, Christophe,Gredin, Patrick,Beaunier, Patricia,Kanger, T?nis,T?nsuaadu, Kaia,Villemin, Didier,Gruselle, Michel
-
p. 112 - 116
(2014/07/21)
-
- 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)
-
- Mesoporous silica-supported copper-catalysts for homocoupling reaction of terminal alkynes at room-temperature
-
Amine-functionalized mesoporous silica-supported copper catalysts SBA-15@amine-Cu and SBA-15@Oamine-Cu were prepared and proved to be efficient and reusable for homocoupling of terminal alkynes at room temperature with air as the oxidant. SBA-15@amine-Cu exhibited better recyclability than SBA-15@Oamine-Cu. The differences in the catalytic performances of the catalysts could be ascribed to catalyst structure and the interaction between copper and the supports. The as-prepared catalysts were systematically characterized by inductively coupled plasma atomic emission spectroscopy (ICP-AES), high resolution-transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and nitrogen physical adsorption. The analysis indicated that the mesoporous structure of the materials was retained during the immobilization process. XPS results suggested that the as-prepared catalysts were not obtained by a simple physical adsorption of CuCl on the supports. It is noted that, for aliphatic alkynes, the catalytic activity of SBA-15@amine-Cu is even higher than that of the homogeneous copper catalytic system and that of some previously reported heterogeneous systems.
- Li, Hongling,Yang, Min,Zhang, Xia,Yan, Liang,Li, Jing,Qi, Yanxing
-
p. 1343 - 1349
(2013/05/21)
-
- Palladium-catalyzed bond reorganization of 1,3-diynes: An entry to diverse functionalized 1,5-dien-3-ynes
-
A mild and efficient method for the synthesis of functionalized 1,5-dien-3-ynes from 1,3-diynes under PdII catalysis is described. The process allows quick and atom-economical assembly of various dihalo-, haloacyl-, and diacyl-substituted 1,5-dien-3-ynes in high yields. The switch of selectivity in the formation of these dienyne products can be controlled by the choice of catalysis system and reaction conditions.
- Wu, Wanqing,Gao, Yang,Jiang, Huanfeng,Huang, Yubing
-
supporting information
p. 4580 - 4586
(2013/06/05)
-
- Palladium-catalyzed oxidative homocoupling reaction of terminal acetylenes using trans-bidentatable 1-(2-pyridylethynyl)-2-(2-thienylethynyl)benzene
-
Palladium-catalyzed oxidative homocoupling of terminal acetylenes, in air, occurred in the presence of 1-(2-pyridylethynyl)-2-(2-thienylethynyl)benzene as ligand, affording the corresponding conjugated diynes.
- Atobe, Shingo,Sonoda, Motohiro,Suzuki, Yuki,Yamamoto, Takuya,Masuno, Haruna,Shinohara, Hiroyuki,Ogawa, Akiya
-
p. 359 - 370
(2013/03/28)
-
- Nanosized Pd(0)-arabinogalactan composites as catalysts in the Sonogashira reaction
-
Zero-valent palladium nanoparticles stabilized by arabinogalactan polysaccharide matrix were successfully used for the first time as phosphine-free catalyst in the cross-coupling of terminal alkynes with aryl and hetaryl halides.
- Parshina,Tantsyrev,Grishchenko,Trofimov
-
p. 412 - 416
(2013/07/26)
-
- Importance of bases on the copper-catalyzed oxidative homocoupling of terminal alkynes to 1,4-disubstituted 1,3-diynes
-
Copper-catalyzed, solvent-free oxidative homocoupling of terminal alkynes can be performed to 1,3-diynes in good to excellent yields in the absence of any additives, using air as environmentally friendly oxidant and the occurrence of water as an exclusive byproduct in the whole process. It is shown that AcO - of copper (II) acetate catalyst may take the role of base and found that the homocoupling cannot occur using weakly basic copper salt catalysts such as CuBr, CuCl, or CuI. Thus, the bases are absolutely necessary in the process of the homocoupling of terminal alkynes. 2012 Elsevier Ltd. All rights reserved.
- Niu, Xinjiang,Li, Chunju,Li, Jian,Jia, Xueshun
-
supporting information
p. 5559 - 5561,3
(2020/07/31)
-
- Practical oxidative homo- and heterocoupling of terminal alkynes catalyzed by immobilized copper in MCM-41
-
A practical oxidative homo- and heterocoupling of terminal alkynes was achieved in CH2Cl2 at 25 °C by using a 3-(2-aminoethylamino)propyl-functionalized MCM-41-immobilized copper(I) complex (MCM-41-2N-CuI, 1 mol-%) as the catalyst, piperidine (0.1 or 3 equiv.) as the base, and air as the environmentally friendly co-oxidant, yielding a variety of symmetrical and unsymmetrical 1,4-disubstituted 1,3-diynes in good to excellent yields. This heterogeneous copper catalyst showed a higher catalytic activity than CuI and can be recovered and recycled by a simple filtration of the reaction mixture and used for at least 10 consecutive runs without any decrease in activity. A practical oxidative homo- and heterocoupling of terminal alkynes was achieved in CH2Cl2 at 25 °C by using a 3-(2-aminoethylamino)propyl-functionalized MCM-41-immobilized copper(I) complex (MCM-41-2N-CuI, 1 mol-%) as the catalyst and air as the environmentally friendly oxidant, yielding a variety of symmetrical and unsymmetrical 1,4-disubstituted 1,3-diynes in good to excellent yields.
- Xiao, Ruian,Yao, Ruiya,Cai, Mingzhong
-
experimental part
p. 4178 - 4184
(2012/09/22)
-
- A new tetraarylcyclopentadienone based low molecular weight gelator: Synthesis, self-assembly properties and anion recognition
-
A new class of tetraarylcyclopentadienones bearing 3-hydroxy-1-propynyl substituents has been synthesized. One of them, 3,4-bis (4-(3-hydroxy-3- methylbut-1-ynyl) phenyl)-2,5-diphenylcyclopenta-2,4-dienone, exhibits pronounced aggregation properties in various organic solvents responding to thermal and ultrasound stimuli and represents the first example of a tetraarylcyclopentadienone based low molecular weight organogelator. The hydroxydimethyl group on the ethynyl substituent proved to be essential to perform the gelation process. The 1H NMR analysis and FT-IR spectroscopy suggested that the intermolecular π-π and hydrogen bonding interactions of the gelator with the solvent are the main driving forces for the supramolecular assembly. The SEM images of xerogels show the characteristic gelation morphologies of 3D fibrous network structures. Fluorescence and UV/Vis absorption studies provided more information to define the molecular packing model in the gelation state. In addition the obtained gels show selective response to the fluoride anion. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2012.
- Boiani, Mattia,Baschieri, Andrea,Cesari, Cristiana,Mazzoni, Rita,Stagni, Stefano,Zacchini, Stefano,Sambri, Letizia
-
body text
p. 1469 - 1478
(2012/07/31)
-
- Rational design of a palladium-catalyzed Csp-Csp cross-coupling reaction inspired by kinetic studies
-
Less is More: A highly selective Pd-catalyzed Csp-Csp cross-coupling reaction between terminal alkynes and 1-bromoacetylenes has been developed. Catalyst loading is low (only 0.0001-0.01 mol % of Pd is required) and provides products with high selectivities and good to excellent yields under mild conditions. TBAB=tetrabutylammonium bromide, TON=turnover number. Copyright
- Weng, Yue,Cheng, Ben,He, Chuan,Lei, Aiwen
-
supporting information
p. 9547 - 9551
(2012/10/30)
-
- 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)
-
- Organic reaction in Solkane 365 mfc: Homocoupling reaction of terminal alkynes
-
Solkane 365 mfc is proven to be an environmentally benign alternative solvent for the homocoupling reaction of terminal alkynes catalyzed by CuCl/TMEDA under air at room temperature. A variety of terminal alkynes, including aromatic, heteroaromatic and aliphatic alkynes, were cleanly transformed into 1,3-diynes within a short period in high to excellent yields up to 98%. The Royal Society of Chemistry.
- Kusuda, Akihiro,Xu, Xiu-Hua,Wang, Xin,Tokunaga, Etsuko,Shibata, Norio
-
supporting information; experimental part
p. 843 - 846
(2011/05/15)
-
- An efficient copper-catalyzed homocoupling of terminal alkynes to give symmetrical 1,4-disubstituted 1,3-diynes
-
A facile and efficient pathway for the copper iodide and ligand N,N,N',N'-tetramethylethane-1,2-diamine promoted homocoupling reaction of terminal alkynes under ambient temperature and air as an oxidant was reported. The alkynes, including aromatic alkynes and aliphatic alkynes, could afford the symmetrical 1,4-disubstituted 1,3-diynes in good to excellent yields. Copyright
- Zhang, Songlin,Liu, Xiaoyan,Wang, Tongqiang
-
supporting information; experimental part
p. 1463 - 1466
(2011/08/07)
-
- 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)
-
- 3,4-dihalo-2(5H)-furanones: A novel oxidant for the Glaser coupling reaction
-
5-Alkoxy-3,4-dihalo-2(5H)-furanones could be used as a kind of novel oxidant in the Glaser coupling reaction. The screening of reaction conditions showed that both PdCl2(PPh3)2 and 3,4-dichloro-5-methoxy-2(5H)-furanone played crucial roles in the reaction. A possible reaction mechanism was proposed according to the reactivity of 3,4-dihalo-2(5H)-furanones. The new method easily allows the syntheses of alkyl and aryl substituted 1,3-diyne compounds. However, carbyne polymer was unexpectedly obtained when using trimethylsilyl acetylene as the substrate under the Glaser reaction condition.
- Li, Jian-Xiao,Liang, Hao-Ran,Wang, Zhao-Yang,Fu, Jian-Hua
-
experimental part
p. 507 - 513
(2011/12/16)
-
- 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)
-
- 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)
-
- 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)
-
- 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 alternative CuCl-piperidine-catalyzed oxidative homocoupling of terminal alkynes affording 1,3-diynes in air
-
CuCl with the use of a catalytic amount of piperidine as additive shows high catalytic activity for the oxidative homocoupling reactions of terminal alkynes in toluene at 60 ?C in air to afford 1,3-diynes in high yields. Copyright
- Zheng, Qingwei,Hua, Ruimao,Wan, Youzhi
-
experimental part
p. 314 - 316
(2010/08/20)
-
- 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)
-
- Transition-metal-free homocoupling of 1-haloalkynes: A facile synthesis of symmetrical 1,3-diynes
-
Symmetrical 1,3-diyne compounds can be easily synthesized via a transition-metal-free homocoupling reaction of 1-haloalkynes without base and oxidant. The method shows excellent functional group compatibility and high yields.
- Chen, Zhengwang,Jiang, Huanfeng,Wang, Azhong,Yang, Shaorong
-
supporting information; experimental part
p. 6700 - 6703
(2010/12/19)
-
- 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; experimental part
p. 709 - 712
(2009/08/12)
-
- Homocoupling reaction of terminal alkynes catalyzed by a reusable cationic 2,2′-bipyridyl palladium(II)/CuI system in water
-
A cationic 2,2′-bipyridyl palladium(II)/CuI system was proven to be a reusable and highly efficient catalyst for the homocoupling of terminal alkynes at room temperature using water as a solvent in the presence of TBAB under aerobic conditions. For aromatic terminal alkynes, the reaction was performed either with or without I2 as an oxidant; the addition of I 2 was required when aliphatic terminal alkynes were used as a substrate for the homocoupling reaction. In the presence of 0.0001-1 mol% palladium catalyst and 1 mol% CuI, a variety of terminal alkynes were homocoupled in good to excellent yields. The water-soluble catalytic system was separated from the organic products by extraction and the residual aqueous solution showed activity for reuse for several cycles without a significant decrease in activity.
- Chen, Shao-Nung,Wu, Wei-Yi,Tsai, Fu-Yu
-
experimental part
p. 269 - 274
(2010/04/22)
-
- 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)
-
- 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)
-
- Cyclopalladated ferrocenylimines: efficient catalysts for homocoupling and Sonogashira reaction of terminal alkynes
-
A novel pathway for homocoupling of terminal alkynes has been described using cyclopalladated ferrocenylimine 1 or 2/CuI as catalyst in the air. This catalytic system could tolerate several functional groups. The palladacycle 2 in the presence of n-Bu4NBr as an additive could be applied to Sonogashira cross-coupling reaction of aryl iodides, aryl bromides, and some activated aryl chlorides with terminal alkynes under amine- and copper-free conditions, mostly to give moderate to excellent yields.
- Yang, Fan,Cui, Xiuling,Li, Ya-nan,Zhang, Jinli,Ren, Ge-rui,Wu, Yangjie
-
p. 1963 - 1969
(2007/10/03)
-