scholarly journals Isolation of bis(copper) key intermediates in Cu-catalyzed azide-alkyne “click reaction”

2015 ◽  
Vol 1 (5) ◽  
pp. e1500304 ◽  
Author(s):  
Liqun Jin ◽  
Daniel R. Tolentino ◽  
Mohand Melaimi ◽  
Guy Bertrand
Keyword(s):  
Direct Observation ◽  
Copper Complexes ◽  
Click Reaction ◽  
Life Sciences ◽  
Dipolar Cycloaddition ◽  
Dinuclear Complexes ◽  
Chemical Transformations ◽  
Terminal Alkyne ◽  
Mechanistic Studies ◽  
Copper Acetylide

The copper-catalyzed 1,3-dipolar cycloaddition of an azide to a terminal alkyne (CuAAC) is one of the most popular chemical transformations, with applications ranging from material to life sciences. However, despite many mechanistic studies, direct observation of key components of the catalytic cycle is still missing. Initially, mononuclear species were thought to be the active catalysts, but later on, dinuclear complexes came to the front. We report the isolation of both a previously postulated π,σ-bis(copper) acetylide and a hitherto never-mentioned bis(metallated) triazole complex. We also demonstrate that although mono- and bis-copper complexes promote the CuAAC reaction, the dinuclear species are involved in the kinetically favored pathway.

Preparation of New Polyols Based on Cis-1,4-Polyisoprene by Using 1,3-Dipolar Cycloaddition

2013 ◽  
Vol 844 ◽  
pp. 381-384
Author(s):  
Ekasit Anancharoenwong ◽  
Jean Francois Pilard ◽  
Irène Campistron ◽  
Albert Laguerre ◽  
Frédéric Gohier ◽  
...  
Keyword(s):  
Ring Opening ◽  
Click Reaction ◽  
Value Added ◽  
Polyol Synthesis ◽  
Sodium Ascorbate ◽  
Dipolar Cycloaddition ◽  
Epoxide Ring ◽  
Terminal Alkyne ◽  
Epoxide Ring Opening ◽  
Model Molecule

This research focuses on synthesis and modification of polyol precursors derived from cis-1,4-polyisoprene (PI). These new polyol precursors can be converted to high value-added polyurethane (PU). The epoxidized hydroxytelechelic PI (EHTPI) prepared by chemical modification from PI was used as starting material for polyol synthesis. 1,3-Dipolar cycloaddition between a terminal alkyne and an azide has rapidly become the most popular click reaction. We applied this reaction to couple azide-functionalized PI and alkyne-functionalized sugar for preparing polyols. For azide functionalization, 1-methyl epoxidized cyclohexane was used as a model molecule, and various conditions for epoxide ring opening of 1-methyl epoxidized cyclohexane and EHTPI were investigated. The cycloaddition of alkyne and azide was carried out in the presence of sodium ascorbate and copper sulfate. The polyol precursors obtained might be used to prepare biodegradable polyol PU.

1,3-dipolar cycloaddition in the synthesis of glycoconjugates of natural chlorins and bacteriochlorins

2009 ◽  
Vol 13 (03) ◽  
pp. 336-345 ◽  
Author(s):  
Mikhail A. Grin ◽  
Ivan S. Lonin ◽  
Anna A. Lakhina ◽  
Elena S. Ol'shanskaya ◽  
Alexey I. Makarov ◽  
...  
Keyword(s):  
Triple Bond ◽  
Tautomeric Form ◽  
Click Reaction ◽  
Copper Cation ◽  
Water Soluble ◽  
Dipolar Cycloaddition ◽  
Nmr Studies ◽  
Metal Free ◽  
Cu Complex ◽  
Derivatives Of

Glucose-, galactose- and lactose-containing photosensitizers based on derivatives of chlorophyll a and bacteriochlorophyll a were synthesized with the use of [3+2] cycloaddition between sugar azides and triple bond derivatives of chlorins and bacteriochlorins. Unlike bacteriochlorin cycloimide, chlorin was detected to form a Cu -complex during the click reaction. An approach to the synthesis of metal-free glycosylated chlorins was developed with the use of "protection" by Zn 2+ cation and subsequent demetalation. It is based on the action of alkynyl chlorin e6 derivative Zn -complex, which is resistant to the substitution by copper cation. Bacteriochlorin p cycloimide conjugate with per-acetylated β-D-lactose was obtained and shown to become water-soluble after unblocking of the lactose hydroxy functions. NMR studies allowed for the elucidation of structure, tautomeric form and conformation of the obtained compounds.

scholarly journals Crystal structures of μ-oxalato-bis[azido(histamine)copper(II)] and μ-oxalato-bis[(dicyanamido)(histamine)copper(II)]

2015 ◽  
Vol 71 (11) ◽  
pp. 1379-1383 ◽  
Author(s):  
Chen Liu ◽  
Khalil A. Abboud
Keyword(s):  
Hydrogen Bonds ◽  
Copper Complexes ◽  
Copper Ions ◽  
Side Chain ◽  
Dinuclear Complexes ◽  
Compound I ◽  
Coordination Site ◽  
Oxalate Ligand ◽  
Compound Ii ◽  
Neighboring Molecule

The title compounds, μ-oxalato-κ4O1,O2:O1′,O2′-bis[[4-(2-aminoethyl)-1H-imidazole-κ2N3,N4](azido-κN1)copper(II)], [Cu2(C2O4)(N3)2(C5H9N3)2], (I), and μ-oxalato-κ4O1,O2:O1′,O2′-bis[[4-(2-aminoethyl)-1H-imidazole-κ2N3,N4](dicyanamido-κN1)copper(II)], [Cu2(C2O4)(C2N3)2(C5H9N3)2], (II), are two oxalate-bridged dinuclear copper complexes. Each CuIIion adopts a five-coordinate square-pyramidal coordination sphere where the basal N2O2plane is formed by two O atoms of the oxalate ligand and two N atoms of a bidentate chelating histamine molecule. The apical coordination site in compound (I) is occupied by a monodentate azide anion through one of its terminal N atoms. The apical coordination site in compound (II) is occupied by a monodentate dicyanamide anion through one of its terminal N atoms. The molecules in both structures are centrosymmetric. In the crystals of compounds (I) and (II), the dinuclear complexes are linked through N—H...Xand C—H...X(X= N, O) hydrogen bonds where the donors are provided by the histamine ligand and the acceptor atoms are provided by the azide, dicyanamide, and oxalate ligands. In compound (I), the coordinatively unsaturated copper ions interact with the histamine ligandviaa C—H...Cu interaction. The coordinatively unsaturated copper ions in compound (II) interactviaa weak N...Cu interaction with the dicyanamide ligand of a neighboring molecule. The side chain of the histamine ligand is disordered over three sets of sites in (II).

scholarly journals Silver-catalysed azide–alkyne cycloaddition (AgAAC): assessing the mechanism by density functional theory calculations

2016 ◽  
Vol 3 (9) ◽  
pp. 160090 ◽  
Author(s):  
Biswadip Banerji ◽  
K. Chandrasekhar ◽  
Sunil Kumar Killi ◽  
Sumit Kumar Pramanik ◽  
Pal Uttam ◽  
...  
Keyword(s):  
Density Functional ◽  
Click Reaction ◽  
Cycloaddition Reaction ◽  
Triazole Ring ◽  
Density Functional Theory Calculations ◽  
Dipolar Cycloaddition ◽  
Reaction Conditions ◽  
Functional Theory ◽  
Click Reactions ◽  
Counter Ions

‘Click reactions’ are the copper catalysed dipolar cycloaddition reaction of azides and alkynes to incorporate nitrogens into a cyclic hydrocarbon scaffold forming a triazole ring. Owing to its efficiency and versatility, this reaction and the products, triazole-containing heterocycles, have immense importance in medicinal chemistry. Copper is the only known catalyst to carry out this reaction, the mechanism of which remains unclear. We report here that the ‘click reactions’ can also be catalysed by silver halides in non-aqueous medium. It constitutes an alternative to the well-known CuAAC click reaction. The yield of the reaction varies on the type of counter ion present in the silver salt. This reaction exhibits significant features, such as high regioselectivity, mild reaction conditions, easy availability of substrates and reasonably good yields. In this communication, the findings of a new catalyst along with the effect of solvent and counter ions will help to decipher the still obscure mechanism of this important reaction.

Gold-Catalyzed Formal Dehydro-Diels-Alder Reactions of Ene-Ynamide Derivatives Bearing Terminal Alkyne Chains: Scope and Mechanistic Studies

2018 ◽  
Vol 130 (41) ◽  
pp. 13791-13795 ◽  
Author(s):  
Qing Zhao ◽  
David Fabian León Rayo ◽  
Dominic Campeau ◽  
Martin Daenen ◽  
Fabien Gagosz
Keyword(s):  
Diels Alder ◽  
Terminal Alkyne ◽  
Mechanistic Studies

Ethenesulfonyl Fluoride (ESF) and Its Derivatives in SuFEx Click Chemistry and More

Synthesis ◽  
2019 ◽  
Vol 52 (05) ◽  
pp. 673-687 ◽  
Author(s):  
Yan-Ping Meng ◽  
Shi-Meng Wang ◽  
Wan-Yin Fang ◽  
Zhi-Zhong Xie ◽  
Jing Leng ◽  
...  
Keyword(s):  
Organic Chemistry ◽  
Click Chemistry ◽  
Exchange Reaction ◽  
Organic Synthesis ◽  
Medicinal Chemistry ◽  
Materials Science ◽  
Click Reaction ◽  
Chemical Properties ◽  
Chemical Transformations ◽  
Absolute Reliability

The sulfur(VI) fluoride exchange reaction (SuFEx), developed by Sharpless and co-workers in 2014, is a new category of click reaction that creates molecular connections with absolute reliability and unprecedented efficiency through a sulfur(VI) hub. Ethenesulfonyl fluoride (ESF), as one of the most important sulfur(VI) hubs, exhibits extraordinary reactivity in SuFEx click chemistry and organic synthesis. This review summarizes the chemical properties and applications of ESF in click chemistry, organic chemistry, materials science, medicinal chemistry and in many other fields related to organic synthesis.1 Introduction2 Chemical Transformations of ESF3 Chemical Transformations of 2-Arylethenesulfonyl Fluorides4 Novel SuFEx Reagents Derived from ESF5 Applications of ESF Derivatives in Medicinal Chemistry6 Applications of ESF Derivatives in Materials Science7 Conclusion

scholarly journals Cupric oxide nanowires on three-dimensional copper foam for application in click reaction

RSC Advances ◽  
2017 ◽  
Vol 7 (16) ◽  
pp. 9567-9572 ◽  
Author(s):  
Chunxia Wang ◽  
Fan Yang ◽  
Yan Cao ◽  
Xing He ◽  
Yushu Tang ◽  
...  
Keyword(s):  
Thermal Oxidation ◽  
Heterogeneous Catalysts ◽  
Click Reaction ◽  
Cupric Oxide ◽  
Three Dimensional ◽  
Dipolar Cycloaddition ◽  
Oxide Nanowires ◽  
Copper Foam ◽  
Additional Support ◽  
Cu Foam

CuO nanowires can be synthesized by facile thermal oxidation of 3D Cu foam in air, which were found to be effective heterogeneous catalysts for the 1,3-dipolar cycloaddition reactions without using any additional support and bases.

Mechanistic studies in model quercetinase reactions using flavonolato copper complexes

1993 ◽  
Vol 51 (1-2) ◽  
pp. 148 ◽  
Author(s):  
É. Balogh-Hergovich ◽  
J. Kaizer ◽  
G. Speier ◽  
M. Czugler
Keyword(s):  
Copper Complexes ◽  
Mechanistic Studies
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