The Huisgen 1,3-dipolar cycloaddition reaction of organic azides and alkynes has gained considerable attention in recent years due to the introduction in 2001 of Cu(1) catalysis by Tornoe and Meldal, leading to a major improvement in both rate and regioselectivity of the reaction, as realized independently by the Meldal and the Sharpless laboratories. The great success of the Cu(1) catalyzed reaction is rooted in the fact that it is a virtually quantitative, very robust, insensitive, general, and orthogonal ligation reaction, suitable for even biomolecular ligation and in vivo tagging or as a polymerization reaction for synthesis of long linear polymers. The triazole formed is essentially chemically inert to reactive conditions, e.g. oxidation, reduction, and hydrolysis, and has an intermediate polarity with a dipolar moment of ∼5 D. The basis for the unique properties and rate enhancement for triazole formation under Cu(1) catalysis should be found in the high ∆G of the reaction in combination with the low character of polarity of the dipole of the noncatalyzed thermal reaction, which leads to a considerable activation barrier. In order to understand the reaction in detail, it therefore seems important to spend a moment to consider the structural and mechanistic aspects of the catalysis. The reaction is quite insensitive to reaction conditions as long as Cu(1) is present and may be performed in an aqueous or organic environment both in solution and on solid support.

Cu-catalyzed azide-alkyne cycloaddition.

The modification of polymers after the successful achievement of a polymerization process represents an important task in macromolecular science. Cycloaddition reactions, among them the metal catalyzed azide/alkyne ‘click’ reaction (a variation of the Huisgen 1,3-dipolar cycloaddition reaction between terminal acetylenes and azides) represents an important contribution towards this endeavor. They combine high efficiency (usually above 95%) with a high tolerance of functional groups and solvents, as well as moderate reaction temperatures (25–70 °C). The present review assembles recent literature for applications of this reaction in the field of polymer science (linear polymers, dendrimers, gels) as well as the use of this and related reactions for surface modification on carbon nanotubes, fullerenes, and on solid substrates, and includes the authors own publications in this field. A number of references (>100) are included.

http://www.c2p2-cpe.com/imgBase/download/Click%20Review.pdf

‘Click’ Chemistry in Polymer and Materials Science

Department of Chemistry, William Mong Institute of Nano Science and Technology, Bioengineering Graduate Program, The Hong Kong University of Science & Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong, China, and Department of Polymer Science and Engineering, Key Laboratory of Macromolecular Synthesis and Functionalization of the Ministry of Education, Institute of Biomedical Macromolecules, Zhejiang University, Hangzhou 310027, China

Acetylenic polymers: syntheses, structures, and functions.

Electric field poled organic electro-optic materials: state of the art and future prospects.

The metal catalyzed azide/alkyne ‘click’ reaction (a variation of the Huisgen 1,3-dipolar cycloaddition reaction between terminal acetylenes and azides) has vastly increased in broadness and application in the field of polymer science. Thus, this reaction represents one of the few universal, highly efficient functionalization reactions, which combines both high efficiency with an enormously high tolerance of functional groups and solvents under highly moderate reaction temperatures (25–70 °C). The present review assembles an update of this reaction in the field of polymer science (linear polymers, surfaces) with a focus on the synthesis of functionalized polymeric architectures and surfaces.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/marc.200800089

'Click' Chemistry in Polymer and Material Science: An Update

Two series of polyurethanes (P1−P10) containing NLO chromophores as side chains were prepared, in which the size of isolation groups was changed from small atoms to much larger groups such as carbazolyl groups. The polymers were well characterized. The tested NLO properties of the polymers demonstrate that the NLO values and the poling efficiency of the polymers are not always improved with increasing of the size of isolation spacer, and for a given chromophore moiety, there is a suitable isolation group present to boost its microscopic β value to possibly higher macroscopic NLO property efficiently.

Structural Control of the Side-Chain Chromophores To Achieve Highly Efficient Nonlinear Optical Polyurethanes

Convenient attachment of highly polar azo chromophore moieties to disubstituted polyacetylene through polymer reactions by using click chemistry

By modifying the synthetic procedure, the previous reported impossible approach was successfully utilized to construct new azo-chromophore-containing hyperbranched polymers (HP1 and HP2) from AB2 m...

New Azo-Chromophore-Containing Hyperbranched Polytriazoles Derived from AB2 Monomers via Click Chemistry under Copper(I) Catalysis

A new synthetic strategy was developed to prepare polyphosphazenes with second-order nonlinear optical chromophore in which sulfonyl groups are the acceptors. Thus, polyphosphazenes P1 and P2 that contain aniline or indole groups as side chains were obtained from a highly reactive macromolecular intermediate, poly(dichlorophosphazene), by nucleophilic substitution reaction. Then a post-azo coupling of p-ethylsulfonylbenzenediazonium fluoroborate or p-octylsulfonylbenzenediazonium fluoroborate toward the aniline or indole ring in P1 and P2 afforded the sulfonyl-based chromophore-functionalized polyphosphazenes P3, P4, and P5. The polymers exhibit good solubility in common organic solvents and are thermally stable. The maximum absorption appeared at about 440 nm in P3, while that of P4 was at about 393 nm, which were blue-shifted about 52 and 32 nm, respectively, compared to the corresponding chromophores with nitro acceptor and resulted in a wider transparency window. The poled films of P3 and P4 exhibits ...

A New Postfunctional Approach To Prepare Second-Order Nonlinear Optical Polyphophazenes Containing Sulfonyl-Based Chromophore

An Attempt To Modify Nonlinear Optical Effects of Polyurethanes by Adjusting the Structure of the Chromophore Moieties at the Molecular Level Using “Click” Chemistry

Jingui Qin

Papers

Structural Control of the Side-Chain Chromophores To Achieve Highly Efficient Nonlinear Optical Polyurethanes

Convenient attachment of highly polar azo chromophore moieties to disubstituted polyacetylene through polymer reactions by using click chemistry

New Azo-Chromophore-Containing Hyperbranched Polytriazoles Derived from AB2 Monomers via Click Chemistry under Copper(I) Catalysis

A New Postfunctional Approach To Prepare Second-Order Nonlinear Optical Polyphophazenes Containing Sulfonyl-Based Chromophore

An Attempt To Modify Nonlinear Optical Effects of Polyurethanes by Adjusting the Structure of the Chromophore Moieties at the Molecular Level Using “Click” Chemistry