Synthesis of triazolyl-alkylphosphonate starting from ω-azidoalkylphosphonates or ω-alkynylphosphonates

1,2,3-Triazolyl-alkylphosphonates are synthesised according to a Huisgen 1,3-dipolar cycloaddition catalysed by copper salts. The cycloaddition of either an alkynylphosphonate with an azidoalkane or an azido-phosphonate with an alkyne is achieved in high yield and regiospecifically. As an illustration of the functionalisation of aromatic ligands by using the catalytic version of the Huisgen reaction, the coupling of 3-ethynyl-1,10-phenanthroline with azidoalkylphosphonate is reported.     

‘ClickCarb’: modular sugar based ligands via click chemistry

Reported is a modular approach for the synthesis of a number of structurally diverse ligands derived from carbohydrates. The use of the highly functional hydroxy amino azide 1 derived from glucosamine allows the synthesis of a number of useful ligands for organic and organometallic catalyses. The key step of the approach is the Huisgen cycloaddition of the anomeric sugar azide and diverse alkynes.     

The Huisgen 1,4-dipolar cycloaddition involving isoquinoline, dimethyl butynedioate and activated styrenes: a facile synthesis of tetrahydrobenzoquinolizine derivatives

A three-component reaction involving isoquinoline, dimethyl butynedioate and electrophilic styrenes is described. The reaction proceeds through a Huisgen 1,4-dipolar cycloaddition pathway.     

Polyethylenes bearing a terminal porphyrin group

An α-[Cu(II)-porphyrin]-polyethylene was synthesized for the first time using copper catalyzed 1,3-dipolar azide-alkyne Huisgen cycloaddition yielding highly colored moiety-substituted polyethylene.     

The three-component reaction of dicarbomethoxycarbene, aldehydes, and beta-nitrostyrenes: a stereoselective synthesis of substituted tetrahydrofurans

The Rh(II)-catalyzed reaction of dimethyl diazomalonate with aryl aldehydes and beta-nitrostyrenes results in the formation of highly substituted tetrahydrofurans. The reaction may be considered to involve the Huisgen dipolar cycloaddition of the carbonyl ylide, generated from the dicarbomethoxycarbene and the aldehyde, to the beta-nitrostyrene. The diastereoselectivity of the reaction may be attributed to the concerted nature of the carbonyl ylide cycloaddition.     

Synthesis and In Vitro Anticancer Activity of Triazolyl Analogs of Podophyllotoxin,a Naturally Occurring Lignin

Russian Journal of Organic Chemistry - A series of triazolyl-modified podophyllotoxin analogs have been designed and synthesized by utilizing Huisgen 1,3-dipolar cycloaddition in order to develop...     

Synthesis of linked symmetrical [3] and [5]rotaxanes having an oligomeric phenylene ethynylene (OPE) core skeleton as a π-conjugated guest via double intramolecular self-inclusion

Linked symmetrical [3] and [5]rotaxanes consisting of an oligomeric phenylene ethynylene (OPE) framework as a π-conjugated guest moiety and lipophilic permethylated α-cyclodextrins (PM α-CDs), as macrocyclic hosts have been prepared by double intramolecular self-inclusion of an OPE guest unit carrying two PM α-CDs followed by capping with bulky stopper groups using click azide-alkyne Huisgen cycloaddition or Sonogashira coupling. The structures of these linked rotaxanes were determined by MALDI-TOF mass spectrum and two-dimensional NMR spectroscopy.     

A stable fullerene-azide building block for the construction of a fullerene-porphyrin conjugate

A stable C₆₀ derivative bearing an azide functional group was prepared and used as a building block under the copper-mediated Huisgen 1,3-dipolar cycloaddition conditions for the preparation of a fullerene-porphyrin conjugate.     

1-Protected 5-amido 1,2,3-triazoles via ruthenium-catalyzed [3+2] cycloaddition of azides and ynamides

Ynamides react with various azides in the ruthenium-catalyzed Huisgen [3+2] cycloaddition reaction. This ruthenium-catalyzed azide-ynamide cycloaddition reaction yields 1-protected 5-amido 1,2,3-triazoles.     

Diversity-oriented syntheses of 7-substituted lentiginosines

Diversity-oriented synthesis of derivatives of the potent glycosidase inhibitor lentiginosine can be achieved in an efficient and versatile way by two modular approaches on key intermediates. After assembling the indolizidine ring system through 1,3-dipolar cycloaddition of a dihydroxylated pyrroline N-oxide with 4-butenol followed by elaboration of the isoxazolidine moiety, the 7-amino and 7-azido derivatives synthesized can be conjugated with functionalised chains by coupling, respectively, with an amino acid, or an alkyne in copper-catalyzed Huisgen cycloadditions.     

Fast, ligand- and solvent-free copper-catalyzed click reactions in a ball mill

A new, ligand- and solvent-free method for the Huisgen 1,3-dipolar cycloaddition (click reaction) was developed using a planetary ball mill. Besides various alkynes and azides, a propargyl functionalized polymer was converted by mill clicking. Moreover, it was possible to carry out a click polymerization in a ball mill.     

Application of a Double Aza-Michael Reaction in a 'Click, Click, Cy-Click' Strategy: From Bench to Flow

The development of a 'click, click, cy-click' process utilizing a double aza-Michael reaction to generate functionalized 1,2,5-thiadiazepane 1,1-dioxides is reported. Optimization in flow, followed by scale out of the inter-/intramolecular double aza-Michael addition has also been realized using a microwave-assisted, continuous flow organic synthesis platform (MACOS). In addition, a facile one-pot, sequential strategy employing in situ Huisgen cycloaddition post-double aza-Michael has been accomplished, and is applicable to library synthesis.     

Intramolecular Huisgen [3+2] cycloaddition in water: synthesis of fused pyrrolidine–triazoles

The intramolecular alkyne–azide Huisgen [3+2] cycloaddition reaction as a ‘click-chemistry’ reaction without a metal catalyst has been studied under aerobic conditions. The synthesis of various pyrrolidine–triazole hybrid compounds has also been achieved by using this intramolecular cycloaddition reaction in water with complete 1,5-regioselectivity.     

Efficient microwave-assisted synthesis of multivalent dendrimeric peptides using cycloaddition reaction (click) chemistry

Multivalent dendrimeric peptides were synthesized via a microwave-assisted Huisgen 1,3-dipolar cycloaddition between azido peptides and dendrimeric alkynes in yields ranging from 46 to 96%.     

Characterization of a modified silicon-containing arylacetylene resin with POSS functionality

A modified silicon-containing arylacetylene resin with a well-defined organic-inorganic POSS functionality was successfully synthesized by Huisgen azide-alkyne 1,3-dipolar cycloaddition.The POSS hybridized resin exhibits excellent thermal properties which were characterized by differential scanning calorimetry(DSC) and thermogravimetric analyses (TGA).Scanning electron microscope(SEM) was used to characterize fracture surface of the hybridized polymer.The results show that phase separation occurs.The POSS moieties are aggregated each other in the polymer to form 200-400 nm domains.     

Transition states of strain-promoted metal-free click chemistry: 1,3-dipolar cycloadditions of phenyl azide and cyclooctynes

Density functional theory (B3LYP) calculations on the transition states for the Huisgen 1,3-dipolar cycloadditions of phenyl azide with acetylene, cyclooctyne, and difluorocyclooctyne are reported. The low activation energy of the cyclooctyne "strain-promoted" cycloaddition (DeltaE = 8.0) compared to the strain-free acetylene cycloaddition (DeltaE = 16.2) is due to decreased distortion energy (DeltaEd) of cyclooctyne (DeltaDeltaEd = 4.6) and phenyl azide (DeltaDeltaEd = 4.5) to achieve that cycloaddition transition state. Electronegative fluorine substituents on cyclooctyne further increase the rate of cycloaddition by increasing interaction energies.     

Synthesis and properties of chiral thioureas bearing an additional function at a remote position tethered by a 1,5-disubstituted triazole

The synthesis and properties of multifunctional thioureas bearing a variety of functional groups at a position remote from the thiourea moiety are described. A 1,5-disubstituted triazole tether connected with a thiourea and another functional group was synthesized via ruthenium catalyzed Huisgen cycloaddition. We demonstrate the utility of the synthetic thioureas as asymmetric catalysts and probes for the mechanistic elucidation of the course of the Michael reaction of an α,?-unsaturated imide.     

Immobilized polytriazole complexes of copper(I) onto graphene oxide as a recyclable nanocatalyst for synthesis of triazoles

An efficient solid‐supported catalyst for the Huisgen [3 + 2] cycloaddition reaction between azides and alkynes was prepared from copper(I) iodide and 1,2,3‐triazole‐functionalized graphene oxide. This catalyst was then used for the efficient synthesis of β‐hydroxy‐1,2,3‐triazoles giving access to these products in excellent yields. In this protocol, the catalyst was shown to have high activity, air‐stability and recyclability. The formation of copper triazolide is very straightforward and energetically desirable. The catalyst can be isolated from copper‐catalysed azide–alkyne cycloaddition reactions.     

Dendronized linear polymers via "click chemistry"

Dendronized linear polymers are prepared from dendritic azides and poly(vinylacetylene) using "click chemistry." The Cu(I)-catalyzed Huisgen [2 + 3] cycloaddition is quantitative up to the third generation.