巯基-烯点击化学

点击化学自2001年由Sharpless提出后,由于其高效、可靠、高选择性的特点迅速成为药物和高分子材料合成的新方法。随着对点击化学研究的深入,其反应类型在不断增多,应用范围也在不断扩大。自由基或亲核试剂引发的巯基-烯反应作为其中一种新型的点击反应具有点击化学的所有特性。本文从点击化学的概念、特征和类型出发,重点介绍了巯基-烯反应的机理和在合成功能聚合物、制备拓扑结构高分子、表面修饰以及生物药物等方面的应用,并对巯基-烯反应的最新研究成果进行综述,最后展望了巯基-烯的点击化学的发展前景。     

点击化学法修饰氧化石墨烯及其在高分子中的应用研究

点击化学是一种操作简单方便、灵活高效的化学合成方法,对石墨烯的改性具有高效和活性位点可控等特点,是一种新型高效修饰石墨烯的改性法。本文结合点击化学改性石墨烯的特点及在高分子中的应用,将点击化学功能化修饰石墨烯分为共价键点击功能化和非共价键点击功能化,其中共价键结合又可细分为边缘点击功能化改性和表面点击功能化改性。本文介绍了叠氮功能改性剂的制备方法及其修饰石墨烯的点击反应原理,总结了点击功能化石墨烯及氧化石墨烯高分子复合材料的功能特性和应用前景。     

Click Chemistry in Functional Aliphatic Polycarbonates

Click chemistry, one of the most important methods in conjugation, plays an extremely significant role in the synthesis of functional aliphatic polycarbonates, which are a group of biodegradable polymers containing carbonate bonds in their main chains. To date, more than 75 articles have been reported on the topic of click chemistry in functional aliphatic polycarbonates. However, these efforts have not yet been highlighted. Six categories of click reactions (alkyne‐azide reaction, thiol‐ene reaction, Michael addition, epoxy‐amine/thiol reaction, Diels‐Alder reaction, and imine formation) that have been afforded for further post‐polymerization modification of polycarbonates are reviewed. Through this review, a comprehensive understanding of functional aliphatic polycarbonates aims to afford insight on the design of polycarbonates for further post‐polymerization modification via click chemistry and the expectation of the practical application.     

Thiol–Ene Click Chemistry

Following Sharpless′ visionary characterization of several idealized reactions as click reactions, the materials science and synthetic chemistry communities have pursued numerous routes toward the identification and implementation of these click reactions. Herein, we review the radical‐mediated thiol–ene reaction as one such click reaction. This reaction has all the desirable features of a click reaction, being highly efficient, simple to execute with no side products and proceeding rapidly to high yield. Further, the thiol–ene reaction is most frequently photoinitiated, particularly for photopolymerizations resulting in highly uniform polymer networks, promoting unique capabilities related to spatial and temporal control of the click reaction. The reaction mechanism and its implementation in various synthetic methodologies, biofunctionalization, surface and polymer modification, and polymerization are all reviewed.     

Diversity Oriented Clicking (DOC): Divergent Synthesis of SuFExable Pharmacophores from 2‐Substituted‐Alkynyl‐1‐Sulfonyl Fluoride (SASF) Hubs

Diversity Oriented Clicking (DOC) is a unified click‐approach for the modular synthesis of lead‐like structures through application of the wide family of click transformations. DOC evolved from the concept of achieving “diversity with ease”, by combining classic C?C π‐bond click chemistry with recent developments in connective SuFEx‐technologies. We showcase 2‐S ubstituted‐A lkynyl‐1‐S ulfonyl F luorides (SASFs) as a new class of connective hub in concert with a diverse selection of click‐cycloaddition processes. Through the selective DOC of SASFs with a range of dipoles and cyclic dienes, we report a diverse click‐library of 173 unique functional molecules in minimal synthetic steps. The SuFExable library comprises 10 discrete heterocyclic core structures derived from 1,3‐ and 1,5‐dipoles; while reaction with cyclic dienes yields several three‐dimensional bicyclic Diels–Alder adducts. Growing the library to 278 discrete compounds through late‐stage modification was made possible through SuFEx click derivatization of the pendant sulfonyl fluoride group in 96 well‐plates—demonstrating the versatility of the DOC approach for the rapid synthesis of diverse functional structures. Screening for function against MRSA (USA300) revealed several lead hits with improved activity over methicillin.     

硫醇-烯/炔点击化学合成功能聚合物材料

点击化学具有反应条件温和、产率高、速率快、产物容易分离以及高度选择性等优点,成为国内外研究的热点之一。硫醇-烯/炔光化学反应作为新型高效的点击反应近年来备受关注,通过这种方法制备高性能及功能性聚合物材料也是新材料领域的前沿研究内容。本文综述了近年来硫醇-烯/炔点击化学在功能聚合物材料合成中的研究成果,详细介绍了硫醇-烯/炔点击化学的特点、优势及其反应机理,重点归纳了利用硫醇-烯/炔点击化学合成线型、超支化、交联等分子结构的功能聚合物材料的研究进展,并对由这种方法合成功能聚合物的单体特点、反应路线及产物应用进行了阐述,最后对硫醇-烯/炔点击化学的进一步应用前景做了展望。     

DNA-associated click chemistry

This review highlights the most recent advances in click chemistry associated with DNA.Cu[I]-catalyzed azides-alkynes Huisgen cycloadditions(CuAAC)and a strain-promoted alkyne-azide cycloaddition(SPAAC)are two popular click reactions that have great impact in DNA science.The simplicity,versatility,orthogonality,and high efficiency of click reaction along with a stable triazole product have been instrumental for the successful application of this reaction in the field of nucleic acid chemistry.CuAAC and SPAAC reactions have been widely used for DNA modification,including DNA labeling,metallization,conjugation,cross-linking,and ligation.Modified oligodeoxynucleotides obtained from click reaction have been extensively applied in the fields of drug discovery,nanotechnology,bio-conjugation,and material sciences,among others.The most recent advances in the synthesis and applications of clickable DNAs are discussed in detail in this article.     

Layer by Layer Electrode Surface Functionalisation Using Carbon Nanotubes,Electrochemical Grafting of Azide‐Alkyne Functions and Click Chemistry

Ferrocene was covalently bonded to a layer of adsorbed single‐walled carbon nanotubes on a glassy carbon electrode surface using electrochemical grafting and click chemistry. Grafting of the 4‐azidobenzenediazonium salt onto the surface was accomplished by electrochemical reduction. The surface‐bound azide groups, with the use of a copper(I) catalyst, were reacted with ethynylferrocene to form covalent 1,2,3‐triazole bonds by click chemistry. This layer by layer construction of the electrode surface results in stable electrodes by combining good electrical conductivity and increased surface area of the nanotubes with the versatility of the Sharpless click reaction.     

Diversity Oriented Clicking (DOC): Divergent Synthesis of SuFExable Pharmacophores from 2-Substituted-Alkynyl-1-Sulfonyl Fluoride (SASF) Hubs

Diversity Oriented Clicking (DOC) is a unified click-approach for the modular synthesis of lead-like structures through application of the wide family of click transformations. DOC evolved from the concept of achieving “diversity with ease”, by combining classic C−C π-bond click chemistry with recent developments in connective SuFEx-technologies. We showcase 2-S ubstituted-A lkynyl-1-S ulfonyl F luorides (SASFs) as a new class of connective hub in concert with a diverse selection of click-cycloaddition processes. Through the selective DOC of SASFs with a range of dipoles and cyclic dienes, we report a diverse click-library of 173 unique functional molecules in minimal synthetic steps. The SuFExable library comprises 10 discrete heterocyclic core structures derived from 1,3- and 1,5-dipoles; while reaction with cyclic dienes yields several three-dimensional bicyclic Diels–Alder adducts. Growing the library to 278 discrete compounds through late-stage modification was made possible through SuFEx click derivatization of the pendant sulfonyl fluoride group in 96 well-plates—demonstrating the versatility of the DOC approach for the rapid synthesis of diverse functional structures. Screening for function against MRSA (USA300) revealed several lead hits with improved activity over methicillin.     

Synthesis of polysaccharide-b-PEG block copolymers by oxime click

The oxime click reaction is shown to be a straightforward methodology for the synthesis of poly(ethylene glycol) (PEG)-polysaccharide diblock copolymers. The method is applicable to unmodified polysaccharides with a reductive end as demonstrated for dextran, hyaluronic acid and chitosan. Notably the oxime click reaction is applied for the first time to the end modification of polysaccharides.     

点击化学在食品安全检测中的应用研究进展

点击化学因具有反应模块化、无有毒有害副产物、反应效率高等出色的反应性能备受关注,是继组合化学之后又一新型合成技术,在材料表面功能化、大分子聚合物的合成、生物标记等领域得到了广泛应用.点击反应试剂的活性基团易于修饰在其他化学基团上,表明点击反应有望作为中间反应介导特定反应的信号转换或放大.近几年出现了大量基于点击化学构建...     

Surface Functionalization of a γ-Graphyne-like Carbon Material via Click Chemistry

Surface functionalization of carbon materials is of interest in many research fields, such as electrocatalysis, interfacial engineering, and supercapacitors. As an emerging carbon material, γ-graphyne has attracted broad attention. Herein, we report that the surface functionalization of a γ-graphyne-like carbon material ( γ-G1 ) is achieved by immobilizing functional groups via the click chemistry. Texture analysis of aberration-corrected microscopy, X-ray photoelectron spectroscopy, and electrochemistry confirm the successful surface modification of γ-G1 through a strong covalent linkage 1,2,3-triazole. The direct linkage of functional groups on γ-G1 via the click chemistry represents a general method for preparing other functional materials by using γ-graphyne-like materials as a skeleton.     

PEG- and peptide-grafted aliphatic polyesters by click chemistry

Novel aliphatic polyesters with pendent acetylene groups were prepared by controlled ring-opening polymerization and subsequently used for grafting poly(ethylene glycol) and oligopeptide moieties by the Cu(I)-catalyzed addition of azides and alkynes, a type of "click" chemistry. These aliphatic polyesters possess an acetylene graft density that can be tailored by ring-opening copolymerization of alpha-propargyl-delta-valerolactone (1) with epsilon-caprolactone. Since the mild conditions associated with the click reaction are shown to be compatible with the polyester backbone, this method is a generally useful means for grafting numerous types of functionality onto aliphatic polyesters. The amphiphilic graft polyesters prepared in this study are shown to be biocompatible by in vitro cytotoxicity evaluation, suggesting their suitability for a range of biomaterial applications.     

点击化学在拓扑结构聚合物合成中的应用

首先对点击化学进行简述,介绍了点击化学的概况、特征及主要反应类型;随后,重点介绍点击化学在拓扑结构聚合物(包括线形、刷形、星形、环状及树枝状大分子等)合成中的应用,并对这一领域的研究进展进行综述;最后,提出目前点击化学存在的一些问题,并对其发展前景进行展望.     

基于巯基点击反应与RAFT聚合的功能性聚合物合成

可逆加成-裂解链转移聚合(RAFT)由于单体适用面广、聚合条件温和、不受聚合方法的限制等特性, 已经成为活性合成聚合物的有效手段之一。点击化学(click chemistry)由于具有良好的选择性、模块性以及官能团耐受性等特点迅速成为许多研究领域,如药物、聚合物、功能材料等合成的有力工具,同时涌现出了多种基于巯基的点击反应。本文综述了近年来基于巯基的点击反应, 如巯基-烯、巯基-炔、巯基-异氰酸酯、巯基-环氧化物以及巯基-卤代烃等新型点击反应与RAFT聚合相结合在功能性聚合物的制备和修饰中的应用, 相信这两种手段的结合将在其中发挥积极的作用。     

1,3-偶极环加成反应与控制自由基聚合结合制备嵌段共聚物的研究进展

炔基与叠氮基的1,3-偶极环加成反应作为点击化学的精髓,反应高效,条件温和.通过它与控制自由基聚合结合,为制备多种拓扑结构嵌段共聚物提供了新途径,所得嵌段共聚物纯度高,分子量分布较窄.本文就1,3-偶极环加成点击反应与3种控制自由基聚合方法相结合在制备线型及非线型嵌段共聚物方面所取得的成就加以综述,并对今后的发展方向做...     

Topological polymer chemistry by programmed self-assembly and effective linking chemistry

Ongoing challenges in topological polymer chemistry are reviewed. In particular, we focus on recent developments in an “electrostatic self-assembly and covalent fixation (ESA–CF)” process in conjunction with effective linking/cleaving chemistry including a metathesis process and an alkyne–azide click reaction. A variety of novel cyclic polymers having specific functional groups and unprecedented multicyclic macromolecular topologies have been realized by combining intriguing synthetic protocols.     

The synthesis and cationic photopolymerization of monomers based on dicyclopentadiene

Several new epoxide monomers based on dicyclopentadiene (DCPD) were prepared using straightforward reaction chemistry. Those monomer-bearing groups in addition to the epoxy moiety, which can stabilize free radicals, display a pronounced acceleration of the rate of cationic ring-opening polymerization in the presence of diaryliodonium salt photoinitiators. Mechanistic studies conducted with the aid of model compounds have shown that the apparent rate acceleration is due to the free radical chain-induced decomposition of the photoinitiator. One of the chain carriers in this reaction involves a monomer-derived free radical. Also prepared was dicyclopentadiene monomer (V) bearing polymerizable epoxide and 1-propenyl ether groups in the same molecule. The functional groups in V appear to undergo independent vinyl and epoxide ring-opening polymerization. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3427–3440, 1999     

Multisite modification of neomycin B: combined Mitsunobu and click chemistry approach

The aminoglycoside antibiotic neomycin B has been converted into several novel building blocks that can be used for the specific modification of three of the four ring systems. Under carefully controlled conditions, the Mitsunobu reaction can be used to selectively dehydrate the ido ring to give the talo epoxide. Subsequently however, under more forcing conditions, the 2-deoxy streptamine ring undergoes Mitsunobu dehydration to give an aziridine. An unusual remote neighboring group effect was observed. When the primary hydroxyl of the ribose ring was blocked, aziridine formation on the deoxystreptamine ring did not occur. Both the epoxide and epoxide-aziridine neomycin building blocks can be ring-opened with azide and subjected to "click" type chemistry with terminal alkynes to generate a series of new neomycin analogues. These reactions can all be carried out without recourse to O-protecting groups. A detailed conformational analysis by NMR revealed some unexpected conformer preferences in these systems.     

Advance of click chemistry in anion exchange membranes for energy application

Click chemistry has attracted tremendous attention in polymer synthesis due to its high efficiency, considerable yield, and simple synthesis/work-up procedures. Among the various functional polymer materials prepared by click chemistry, anion exchange membrane (AEM) is a kind of polyelectrolyte which contains cations attached to the polymer skeleton. Click chemistry not only provides facile pathways for the preparation of AEMs but also generates diverse architectures of AEMs with robust performance. The commonly used click chemistry in AEMs consists of: (i) Diels-Alder reaction, (ii) thiol-ene, and (iii) Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). This review will focus on the advance of click chemistry in the preparation of AEMs, especially synthetic approaches for different AEMs and their corresponding application in energy-related fields, such as fuel cells, redox flow battery, electrodialysis, and so on.