Abstract Four Cu(I) complexes bearing dihydrobis(2-mercapto-benzimidazolyl)borate and phosphine co-ligands were synthesized and their catalytic activity was investigated in azide-alkyne reactions. These complexes were tested as catalyst system and among them a Cu(I) complex bearing tricyclohexylphosphine ligand, [Cu(Bb)(PCy3], showed superior catalytic activity in water. The introduced ligands are advantageous
A Peerless Aproach: Organophotoredox/Cu(I) Catalyzed, Regioselective, Visible Light Facilitated, Click Synthesis of 1,2,3-Triazoles via Azide–Alkyne [3 + 2] Cycloaddition
作者:Anu Mishra、Pratibha Rai、Madhulika Srivastava、Bhartendu Pati Tripathi、Snehlata Yadav、Jaya Singh、Jagdamba Singh
DOI:10.1007/s10562-017-2156-8
日期:2017.10
mild, one pot, multicomponent copper catalyzed azide alkyne [3 + 2] cycloaddition in the presence of organo photoredox catalyst Eosin Y using EtOH:H2O as reaction medium for the synthesis of substituted 1,2,3-triazoles is reported. A facile regioselective ring opening of epoxides followed by 1, 3 dipolar cycloaddition with alkynes under CFL (Compact fluorescent light) irradiation as a source of visible
CoFe<sub>2</sub>O<sub>4</sub>/Cu(OH)<sub>2</sub> magnetic nanocomposite: an efficient and reusable heterogeneous catalyst for one-pot synthesis of β-hydroxy-1,4-disubstituted-1,2,3-triazoles from epoxides
作者:Ronak Eisavi、Asmar Karimi
DOI:10.1039/c9ra06038c
日期:——
separable CoFe2O4/Cu(OH)2 nanocomposite was prepared and characterized by various techniques such as FESEM, EDS, TEM, XRD, VSM and FT-IR. This novel composite was used as a heterogeneous catalyst for the regioselective synthesis of β-hydroxy-1,4-disubstituted-1,2,3-triazoles from sodium azide, terminal alkynes and structurally different epoxides in water at 60 °C. The formation of the product proceeds
制备了一种可磁分离的CoFe 2 O 4 /Cu(OH) 2纳米复合材料,并通过FESEM、EDS、TEM、XRD、VSM和FT-IR等多种技术对其进行了表征。这种新型复合材料被用作非均相催化剂,用于在 60 °C 的水中从叠氮化钠、末端炔烃和结构不同的环氧化物区域选择性合成 β-羟基-1,4-二取代-1,2,3-三唑。产品的形成通过一种涉及原位的机制在一个锅中进行生成有机叠氮化物中间体,然后与炔烃组分快速闭环。简单的程序、短的反应时间、完美的区域选择性、高产品收率以及使用良性溶剂和无毒催化剂是该协议的显着优势之一。此外,催化剂很容易使用外部磁体分离并重复使用多次,而不会显着损失催化活性或磁性。
Multicomponent Click Synthesis of 1,2,3-Triazoles from Epoxides in Water Catalyzed by Copper Nanoparticles on Activated Carbon
Copper nanoparticles on activated carbon have been found to effectively catalyze the multicomponent synthesis of beta-hydroxy-1,2,3-triazoles from a variety of epoxides and alkynes in water. The catalyst is easy to prepare, reusable at a low copper loading (0.5 mol %), and exhibits higher catalytic activity than some commercially available copper sources. The regio- and stereochemistiy of the reaction has been revised and unequivocally established on the basis of X-ray crystallographic analyses. An NMR experiment has been implemented for the rapid and unmistakable determination of the regiochemistry of the process. Some mechanistic aspects of the reaction have been also undertaken which unveil the participation of copper(I) acetylides.
A concise and simple click reaction catalyzed by immobilized Cu(I) in an ionic liquid leading to the synthesis of β-hydroxy triazoles
作者:Nasseb Singh
DOI:10.1016/j.crci.2015.07.006
日期:2015.12
Résumé This study describes an ecocompatible, concise, and practically reliable approach for the regioselective synthesis of β-hydroxy triazoles via Huisgen's click coupling reaction among varied epoxides, NaN3, and suitable acetylenes catalysed by immobilized Cu(I) in ionic liquid (IL). This one-pot, atom-economic, efficient, and highly regioselective green protocol ensures higher yield of β-hydroxy triazole scaffolds (85–95%). To make the process ecofriendly, this study emphasizes on the catalyst immobilization technique along with its possible recycling that gave a high reaction yield in up to three runs. The structures of all synthesized compounds have been characterized by comparing 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectroscopic data with those reported in the literature.