Copper azide-alkyne cycloaddition

Gramlich PME, Wirges CT, Manetto A, Carell T (2008) Postsynthetic DNA modification through the copper-catalyzed azide-alkyne cycloaddition reaction. Angew Chem Int Ed... 

Another approach for the synthesis of networks relies on the polycondensation of multifunctionalized polyesters with the appropriate multifunctionalized agent, provided that one of the partner is at least tri-functionalized. Toward this end, several reaction have been reported, such as the Michael addition of amines onto acrylates [184], the coupling of ketones and oxyamines [185], the click copper(II)-catalyzed azide-alkyne cycloaddition [186], and esterification reactions [25, 159, 187]. Interestingly, if esterification reactions are used, the crosslinks are then degradable. 

Diaz, D.D., Punna, S., Holzer, P., Mcpherson, A.K., Sharpless, K.B., Fokin, V.V. and Finn, M.G. (2004) Click chemistry in materials synthesis. 1. Adhesive polymers from copper-catalyzed azide-alkyne cycloaddition. J. Polym. Sci. Polym. Chem., 42, 4392. 

Copper(I)-catalyzed azide-alkyne cycloaddition as a selective bioconjugation technique... 

A copper catalysed click (azide-alkyne cycloaddition) reaction has been used to prepare a fluorous-tagged TEMPO catalyst (Figure 7.20). TEMPO is a stable organic free radical that can be used in a range of processes. In this case, its use in metal-free catalytic oxidation of primary alcohols to aldehydes using bleach as the terminal oxidant was demonstrated. The modified TEMPO can be sequestered at the end of the reaction on silica gel 60 and then released using ethyl acetate for reuse in further reactions in this way the TEMPO was used four times with no loss in activity. 

CavalK S, Tipton AR, Overhand M, Kros A (2006) The chemical modification of Hpo-some smfaces via a copper-mediated [3-t2] azide-alkyne cycloaddition monitored by a colorimetric assay. Chem Commim (Camb) 3 0 3193-3195... 

Copper-Catalyzed Azide-Alkyne Cycloaddition (CuAAC)... 

I 10 Copper-Catahfzed Azide-Alkyne Cycloaddition (CuAAQ... 

Copper-catalyzed azide-alkyne cycloaddition producing only 1,4-disub-stituted-1,2,3-triazoles at room temperature in excellent yields 07AA7. 

S.2.2.4. Triazoles from Azides. Cycloadditions of this type constitute a valuable synthetic route to the triazole ring system. This is shown in Scheme 5.30. This combination dates back to the early work of Huis-gen, but in more recent times it was discovered to be subject to catalysis by Cu(I) compounds. The reactions are fast under mild conditions, have high regiospecificity, and occur in a variety of solvents including water. In addition, reaction products are easily isolated. Reactions with these characteristics have become known as comprising click chemistry this term was coined by K. B. Sharpless. The first and most commonly used reaction referred to by this name is indeed the azide-alkyne cycloaddition, and new interest has developed in triazole hemistry since the discoveiy of the copper catalysis. In addition to its use in organic... 

Rinaldi L, Martina K, Baricco F, Rotolo L, Cravotto G. Solvent-free copper-catalyzed azide-alkyne cycloaddition under mechanochemical activation. Molecules 2015 20 2837 9. 

Diaz DD, Punnas Holzer P et al (2004) Click chemistiy in materials synthesis. 1. Adhesive polymers from copper-catalyzed azide-alkyne cycloaddition. Polym Sci Part A Polym Chem... 

The synthesis of probe 75, via procedures similar to those reported previously with some modifications, is outlined in Scheme 18 [74]. Coupling compound 76, already described in the literature [75-77], with the bioactive ligand 77 gave compound 78, which was subsequently reacted with the fluorophore 79 to give probe 75 employing the copper-catalyzed [3 + 2] azide-alkyne cycloaddition [78]. 

The turning point for the above mentioned 1,3-dipolar cycloaddition occurred with the independent discovery that copper(I) not only promotes the speed of the reaction (often referred to as click reaction), but also improves regioselectivity. The copper(I)-catalyzed azide alkyne cycloaddition (CuAAC) of terminal alkenes with organic azides to yield 1,4-disubstituted 1,2,3-triazoles discovered by Meldal [51] and Sharpless [50] exhibits remarkably broad scope and exquisite selectivity [59,60]. The most prominent application of click reactions in recent years has been in drug research [61,62],... 

Photochemically generated phosphonyl radicals are effeetive reducing agents for Cu VCu reduction in copper complexes. It has been shown that the obtained copper(i) species can rapidly catalyse atom transfer radical polymerisation and azide-alkyne cycloadditions in mild conditions, i.e. at ambient temperature and humidity, under an air atmosphere. 

CuAAC Copper-catalyzed azide-alkyne cycloaddition... 

This chapter will serve to highlight recent advances in polymer science that have been aided by the use of click chemistry. The copper(l)-catalyzed azide-alkyne cycloaddition (CuAAC) and thiol-ene reactions will be discussed first, after which the utilization of these chemical transformations in the construction and fimction-ahzation of a multitude of different polymeric materials will be outlined. Particular attention will be focused on the preparation of highly complex polymer architectures, such as dendrimers and star polymers, which exempHfy the essential role that chck chemistry has assumed in the polymer science community. 

Advancements in the mechanistic understanding of the copper-catalyzed azide—alkyne cycloaddition 13BJ02715. 

The alkynyl functionality of alkynones 1 is perfectly suited for subsequent copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) in the sense of an MCR (2015ASC(357)617). A microwave-assisted three-component reaction of aroyl chlorides 4, TMS-substituted acetylene (5a), and benzyl azide (10a) consisting of modified Sonogashira cross-coupling I, desilylation, and CuAAC furnishes 4-disubstituted 1,2,3-triazoles 11 in moderate to excellent yields (Scheme 5) (201 OOL(12)4936). 

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