Zinc mediated azide-alkyne ligation to 1,5- and 1,4,5-substituted 1,2,3-triazoles

From 1-Sulfonyl-4-aryl-1,2,3-triazoles to 1-Allenyl-5-aryl-1,2,3-triazoles

An efficient and highly regioselective synthesis of 1-allenyl-5-aryl-1,2,3-triazoles from 1-sulfonyl-4-aryl-1,2,3-triazoles is disclosed. 1-Sulfonyl-4-aryl-1,2,3-triazoles reacted with propargylic alcohols in the presence of trifluoroboron etherate to furnish 1-allenyl-5-aryl-1,2,3-triazoles. When secondary alcohols were used as substrate, the outcome of the reaction was 1-alkyl-5-aryl-1,2,3-triazoles.

A rapid screening platform for catalyst discovery in azide-alkyne cycloaddition by ICP-MS/MS

We developed a rapid high-throughput screening platform using a modified ICP-MS/MS system for monovalence metal ions catalysts discovery in azide-alkyne cycloaddition. Among the ten monovalence metal ions in the first row of periodic table containing Sc⁺, Ti⁺, V⁺, Cr⁺, Mn⁺, Fe⁺, Co⁺, Ni⁺, Cu⁺, and Zn⁺, five monovalence metal ions of Sc⁺, Co⁺, Ni⁺, Cu⁺ and Zn⁺ ions show relatively stronger catalytic activities than others. The catalytic mechanism of Sc⁺, Co⁺ and Ni⁺ ions is similar to the Cu⁺ ions, but Zn⁺ ions take a different catalytic route. A yields range of 77-98% for azide-alkyne cycloaddition was achieved with Sc⁺, Co⁺, Ni⁺, Cu⁺ and Zn⁺ ions as catalyst, respectively by using a UV laser ablation reactor in 20min, notable that the yields of Co⁺ and Sc⁺ ions were even higher than the common catalyst of Cu⁺ ions. The proposed platform would be used not only for catalyst discovery in azide-alkyne cycloaddition, but also for the discovery of single atom/ion catalysts in other organic reactions.

Regioselective Zn(OAc)2-catalyzed azide–alkyne cycloaddition in water: the green click-chemistry

A new method of azide–alkyne cycloaddition (AAC) in the presence of Zn(OAc)₂ as an inexpensive and environmentally friendly catalyst in neat water has been developed.

Simple ZnEt2as a catalyst in carbodiimide hydroalkynylation: structural and mechanistic studies

Simple ZnEt₂is an efficient catalyst for the addition of terminal alkynes to carbodiimides, through amidinate complexes, and consecutive isocyanate addition and intramolecular cyclohydroamination.

Green click synthesis of β-hydroxy-1,2,3-triazoles in water in the presence of a Cu(ii)–azide catalyst: a new function for Cu(ii)–azide complexes

A new method for preparing 1,2,3-triazols via a [3+2]-cycloaddition reaction is introduced. The effect of reaction temperature on the epoxide ring opening reactions is also investigated.

Palladium-Catalyzed C-H Arylation of 1,2,3-Triazoles

Palladium(II) acetate, in combination with triphenylphosphine, catalyzes direct arylation of 1,4-disubstituted 1,2,3-triazoles effectively. This C–H arylation reaction provides facile access to fully substituted triazoles with well-defined regiochemistry.

Cu-Catalyzed Click Reaction in Carbohydrate Chemistry

Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC), popularly known as the "click reaction", serves as the most potent and highly dependable tool for facile construction of simple to complex architectures at the molecular level. Click-knitted threads of two exclusively different molecular entities have created some really interesting structures for more than 15 years with a broad spectrum of applicability, including in the fascinating fields of synthetic chemistry, medicinal science, biochemistry, pharmacology, material science, and catalysis. The unique properties of the carbohydrate moiety and the advantages of highly chemo- and regioselective click chemistry, such as mild reaction conditions, efficient performance with a wide range of solvents, and compatibility with different functionalities, together produce miraculous neoglycoconjugates and neoglycopolymers with various synthetic, biological, and pharmaceutical applications. In this review we highlight the successful advancement of Cu(I)-catalyzed click chemistry in glycoscience and its applications as well as future scope in different streams of applied sciences.

Metal-Free Three-Component Domino Approach to Phosphonylated Triazolines and Triazoles

An efficient, three-component domino reaction between aldehydes, amines, and the Bestmann-Ohira reagent is reported that enables a general, mild, and straightforward access to 1,4,5-trisubstituted 1,2,3-triazolines and triazoles. The reaction proceeds through a domino-condensation/1,3-dipolar cycloaddition sequence to afford the triazoline derivatives with excellent diastereoselectivity. Moreover, when both amine and aldehyde employed for this reaction are aromatic, a spontaneous oxidation afforded 1,4,5-trisubstituted triazoles in moderate yields.

Rapid screening of copper intermediates in Cu(i)-catalyzed azide–alkyne cycloaddition using a modified ICP-MS/MS platform

Rapid screening of Cu⁺-intermediates by using ⁶³Cu⁺ or ⁶⁵Cu⁺ ions as catalysts in Cu(i)-catalyzed azide–alkyne cycloaddition was realized using an on-line modified ICP-MS/MS platform.

Copper(I)-Catalyzed Interrupted Click Reaction: Synthesis of Diverse 5-Hetero-Functionalized Triazoles

The 5-heterofunctionalized triazoles are important scaffolds in bioactive compounds, but current click reactions (CuAAC) cannot produce these core structures. A copper(I)-catalyzed interrupted click reaction to access diverse 5-functionalized triazoles is reported. Various 5-amino-, thio-, and selenotriazoles were readily assembled in one step in high yields. The reaction proceeds under mild conditions with complete regioselectivity. It also features a broad substrate scope and good functional group compatibility.

Synthesis of functionalized 1,2,3-triazoles using Bi2WO6 nanoparticles as efficient and reusable heterogeneous catalyst in aqueous medium

The regioselective synthesis of functionalized triazoles is achieved using a combination of Bi₂WO₆ nanoparticles (10 mol%) and click conditions from β-nitrostyrenes, phenylacetylene and chalcones with azides.

Mechanism and selectivity for zinc-mediated cycloaddition of azides with alkynes: a computational study

Distortion–interaction analysis and FMO theory were utilized to explain the reactivity and 1,5-regioselectivity of zinc-mediated cycloaddition of azides and alkynes.

An efficient one-pot strategy for the highly regioselective metal-free synthesis of 1,4-disubstituted-1,2,3-triazoles

A simple and efficient metal-free methodology for the regioselective synthesis of 1,4-disubstituted-1,2,3-triazoles by applying a novel inverse electron-demand-1,3-dipolar cycloaddition approach has been developed.