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Functional Nano-Bioconjugates for Targeted Cellular Uptake and Specific Nanoparticle–Protein Interactions
Published in Grunwald Peter, Biocatalysis and Nanotechnology, 2017
Sanjay Mathur, Shaista Ilyas, Laura Wortmann, Jasleen Kaur, Isabel Gessner
Since its introduction by Sharpless and co-workers, the term “click chemistry” is known as one of the most versatile and modular approaches to couple two reactive partners in a facile, selective, reliable and high yield reaction under mild conditions (Kolb et al., 2001). Meanwhile, click chemistry has become one of the most common and reliable methods to link molecules in a covalent fashion and is finding ever-increasing applications in a variety of disciplines including the chemistry of nanomaterials, chemical biology, drug delivery, and medicinal chemistry (Binder, 2008; Hou et al., 2012; Kolb and Sharpless, 2003; Neibert et al., 2013). Typical examples of click chemistry reactions include cycloaddition reactions, such as the 1,3-dipolar family, and hetero Diels–Alder reactions, nucleophilic ringopening reactions of epoxides and aziridines, carbonyl reactions such as formation of hydrazones, Michael additions, and cycloaddition reactions (Jùrgensen, 2000; Adolfsson et al., 1999; Kolb et al., 1994).
Perspective on the Advancements in Conjugated Polymer Synthesis, Design, and Functionality over the Past Ten Years
Published in John R. Reynolds, Barry C. Thompson, Terje A. Skotheim, Conjugated Polymers, 2019
Brian Schmatz, Robert M. Pankow, Barry C. Thompson, John R. Reynolds
Click-chemistry has introduced new synthetic transformations to field of organic synthesis, and its application to conjugated polymer synthesis was inevitable.[63] By definition, click-chemistry allows for the rapid synthesis of desired compounds providing high yields without toxic byproducts or extensive work-up and purification steps. Of the various click-reactions described, the copper-catalyzed azide-alkyne cycloaddition (CuAAC), shown in Figure 3.30A, is one of the most identifiable. This reaction occurs between alkyne and azide functionalized monomers, with a copper catalyst to help activate the alkyne moiety by enhancing its electrophilicity. This methodology was applied towards the synthesis of fluorene, phenylene, and benzothiadiazole containing copolymers, shown in Figure 3.30 as polymers 108 and 109.[64] The polymerization itself was carried out at or near room temperature in tetrahydrofuran affording high yields (>90%), albeit with modest molecular weights (Mn = 6–8.7 kDa). Another click-reaction is the thiol-yne reaction, which occurs between a thiol and an alkyne through a radical-mediated mechanism, shown in Figure 3.30B with polymer 110.[65] This methodology affords high-yielding (>95%) materials with high molecular weights (Mw = 21–61 kDa).[66] However, the radical-mechanism affords cis-trans isomers in a roughly 1:1 ratio, which may hinder the desired electronic or physical characteristics of the polymer.
Green Chemistry and Green Catalysts
Published in Ahindra Nag, Greener Synthesis of Organic Compounds, Drugs and Natural Products, 2022
Ahindra Nag, Himadri Sekhar Maity
Click chemistry encompasses a group of powerful linking reactions that produce diverse molecular entities in medicinal chemistry, biotechnology, materials science and polymer science through one-pot strategy from readily available potential building blocks under simple reaction conditions.23 The term “click chemistry” was introduced by Sharpless.24 The catchy term “click” indicates reactions that are modular in approach, occur irreversibly resulting in high yield of a single product, are efficient, selective and versatile in nature, can be performed in benign and easily removable solvent (like water) without requiring chromatographic purification, and proceed with high reaction specificity (in some cases, with both regio-specificity and stereo-specificity).24–26 Huisgen’s 1,3-dipolar azide-alkyne cycloaddition (AAC) is considered to be an important click reaction for the formation of two regio-isomeric five-membered nitrogen-containing heterocycles, i.e. the 1,4- and 1,5-isomers of substituted 1,2,3-triazoles under thermal conditions.27 Among all the click reactions, Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) for the synthesis of 1,4-disubstituted-1,2,3-triazole via exclusively as well as in a regioselective manner is the jewel in the crown.28 American chemist K.B. Sharpless has referred to this cycloaddition as “the cream of the crop” of click chemistry and “the premier example of a click reaction”.23,28 Analogous ruthenium-catalyzed azide-alkyne cycloaddition (RuAAC) reaction reported by the Sharpless group in 2005 is another example of click reaction for the selective formation of 1,5-disubstituted-1,2,3-triazole in the presence of ruthenium, instead of copper catalyst.29
A study on electro-optical properties of polymer dispersed liquid crystal films doped with barium titanate nanoparticles prepared by nucleophile-initiated thiol-ene click reaction
Published in Liquid Crystals, 2020
Taoyu He, Bo Yang, Li Zhang, Zhiqing Shi, Xinjian Gong, Pengfei Geng, Zhenwei Gao, Yinghan Wang
Since the concept of ‘click chemistry’ was defined in the early 21st by Sharpless, click chemistry has played an important role in a lot of fields such as drug discovery, biomedical material synthesis and material surface modification owing to its outstanding advantages [34–37]. Among it, thiol-ene click chemistry refers to the reaction of the hydrothiolation of carbon-carbon double bond (C = C), with the benefits of fast reaction speed, simple reaction conditions, high yield and strong selectivity [38]. In general, thiol-ene click chemistry can be divided into two types: the radical-initiated thiol-ene click chemistry and the base- or nucleophile-catalysed thiol-Michael addition [39]. In the first one, the initiator absorbs energy from light or heat and cracks, producing free radical to initiate the reaction. In the last one, a base or a nucleophile could weaken the bond energy of the alkene double bond, so that the reaction can be carried out in mild conditions.
Investigation of the arsenic(V) retention performance of the nano-sorbent (M-TACA) synthesized by click chemistry
Published in Journal of Dispersion Science and Technology, 2023
Bilsen Tural, Erdal Ertaş, Servet Tural
In order to functionalize the sorbents used in the removal of environmental pollution, it is important that the reactions utilized are high yields and do not form by-products. Therefore, click chemistry is preferred because it has a reaction efficiency of over 95%, does not form by-products, and is fast, simple to use, easy to purify, versatile and specific to the region.[50] The novelty of this study is the functionalization of magnetic silica with NMDG using Click chemistry and its use in As(V) removal.
NMR spectral, DFT and antibacterial studies of triazole derivatives
Published in Inorganic and Nano-Metal Chemistry, 2023
S. Mohan, P. Navamani, K. I. Dhanalekshmi, K. Jayamoorthy, N. Srinivasan
Click chemistry reactions facilitate adaptive synthetic access toward the accumulation of innovative molecular moieties exploiting a gathering of dependable chemical reactions. Click chemistry plays important role because of the mixture owns only stable compounds, the reaction owns a high yield, energetically highly favorable linking reaction and the purification can be done on large scale to form a desired product in a simple and quantitative way.[4,5] The click chemistry reactions and coupling reactions catalyzed by copper have been created a significant brunt on industrial, biological and synthetic applications.[6,7] To accomplish this category of reaction, readily available Cu (I) salts are used and it has been found that in situ generated Cu (I) catalyst in the homogeneous conditions.[8] The limitations of the above-mentioned catalytic system are high catalyst loading and low yield. Accordingly, an ingenious methodology was developed on behalf of the synthesis of 1,2,3-triazole by utilizing CuO NPs as a catalyst. Nano-sized particles enhance the revealed surface area of active catalyst components; thus, it evidently intensifies the connection between the catalyst and reactants. The exploit of nano catalyst afford exceptional selectivity and recyclability, and furthermore, they are eco-friendly. For this reason, experimental strategy can be economical, greener and also sustainable by formulating nanoparticle-based heterogeneous Catalytic systems. Heterogeneous Ce-CuO nanocatalyst performs as an attractive aspirant for synthesis of innovative triazole-based molecules that′ lead to the recovery and reuse ability of the catalyst without any sustainable loss of activity. Thus, Cu and its derivatives are examples of heterogeneous Cu catalysts adapted to the click reaction.[9–11] Numerous homogeneous and heterogeneous reactions can be executed efficiently by sonication under moderate conditions and short reaction times, resulting in higher yields and greater selectivity.[12] Current research concentrates on identifying innovative catalysts to enhance the effectiveness of this azide-alkyne cycloaddition and A3 coupling reactions. NMR spectroscopy is a recognizable method used to acquire information about the skeletal investigation of an organic molecule. 1H and 13C NMR spectral inspection have been exceptionally employed in gathering stereo dynamical reports on a wide range of the system. It provided data on the effect of electronic and conformational belongings on coupling constants and chemical shifts.[13,14]