Thiol click chemistry

Hoyle CE, Lowe AB, Bowman CN (2010) Thiol-click chemistry a multifaceted toolbox for small molecule and polymer synthesis. Chem Soc Rev 39(4) 1355-1387... 

Hensarling RM, Hoff EA, LeBlanc AP, Guo W, Rahane SB, Patton DL (2013) Photocaged pendent thiol polymer brush surfaces for postpolymerization modifications via thiol-click chemistry. J Polym Sci A Polym Chem 51 1079-1090... 

There now are available a number of alkyl azide compounds that may be used in click chemistry reactions and the Staudinger ligation processes. It is not recommended, however, to use aryl azide compounds, as these are light sensitive and photoreactive as well as highly susceptible to reduction in the presence of thiols. Unfortunately, at the time of this writing there are fewer choices in aryl phosphine compounds to participate in this reaction, as commercial sources of labeling reagents are limited. 

A specific peptide sequence for nuclear targeting (NLS) has been conjugated to gold NRs via click chemistry. In particular, a thiol with an azide end group has been reacted via Huisgen 1,3-dipolar cycloaddition to an alkyne-terminated NLS peptide and then anchored to CTAB-protected gold NRs.250... 

Connal LA, Kinnane CR, ZehMn AN, et al. (2009) Stabilization and functionalization of polymer multilayers and capsules via thiol-ene click chemistry. Chem Mater 21 27-30... 

Click Chemistry in Polymer Science CuAAC and Thiol-Ene Coupling for the Synthesis and Functionalization of Macromolecules... 

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. 

In potentially the ultimate demonstration of the power of click chemistry for the construction of dendrimers, both thiol-ene and CuAAC coupling reactions were combined in a single accelerated growth strategy [133], This rapid synthetic... 

Hyperbranched polymers can be prepared by a variety of techniques, including the polycondensation of AB monomers as originally described by Flory [113], the reaction of A2 + B3 monomers, and self-condensing vinyl polymerization [139-141]. The first report [142] of using click chemistry in the synthesis of hyperbranched materials appeared at about the same time as the initial report for dendrimers prepared using CuAAC however, but much fewer examples have been reported that describe hyperbranched materials involving click chemistry. Nevertheless, these polymers represent an important class of materials, and both CuAAC [142-147] and thiol-ene [148] chemistry have found their way into the hyperbranched hterature. 

A review of click chemistry and its application to material synthesis would not be complete without a discussion of the network-forming abilities of CuAAC and fhiol-ene coupling reactions. In particular, thiol-ene chemistry has been well established in the field, and has been used extensively in network formation for over... 

The ability of thiol-ene click chemistry to retain high efficiency under the most benign reaction conditions was exempHfied by Ritter and Bardts, in the preparation of hydrogels based on methacryhc acid [224]. In this study, poly(methacrylic acid) polymers were modified with cysteamine and aUyl amine to afford complementary thiol-ene reactive polymer chains. Solutions of the polymer pairs in water were mixed in the presence of a radical initiator, and the formation of a highly elastic gel was observed within only 2 h at room temperature. The authors noted that this approach might have broad application for a rapid and straightforward access to hydrogel materials for which the properties could easily be tailored by the choice of the amine modifiers. 

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