Selenolactone as a Building Block toward Dynamic Diselenide-Containing Polymer Architectures with Controllable Topology.

A versatile protocol for the synthesis of a variety of multiresponsive diselenide-containing polymeric architectures was investigated. It consists of a one-pot, two-step process with the generation of a selenol by in situ nucleophilic ring opening of selenolactone with a broad range of amine-containing structures, followed by the transformation of the obtained compounds to the corresponding diselenide through a spontaneous oxidation coupling reaction. After elaboration of this one-pot reaction, a number of routes based on selenolactones have been developed for the successful synthesis of functional, linear, branched, cyclic, and cross-linked polymers via a mild, straightforward process.

One-Pot Modular Synthesis of Functionalized RAFT Agents Derived from a Single Thiolactone Precursor.

In this paper, the straightforward preparation of a range of functionalized trithiocarbonates as RAFT chain transfer agents (CTAs) is presented. The crucial step in the one-pot, three-step reaction sequence is the aminolysis of a thiolactone precursor as it introduces the desired functional handle (double bond, hydroxyl, furan, protected amine, ..

Macromolecular Coupling in Seconds of Triazolinedione End-Functionalized Polymers Prepared by RAFT Polymerization.

The ultrafast and additive-free triazolinedione-click reaction with electron rich (di)enes is a powerful method for the ultrafast ligation of polymer segments. A versatile method is described for the introduction of clickable TAD end groups in various polymer segments, using reversible addition-fragmentation chain transfer polymerization. These triazolinedione-functionalized prepolymers were subsequently used for macromolecular functionalization with a low molecular weight diene and block copolymer synthesis of different types within seconds, at ambient conditions, through the coupling with diene-functionalized polymers such as poly(ethylene glycol) and poly(isobornyl acrylate).

Double Modification of Polymer End Groups through Thiolactone Chemistry.

A straightforward synthetic procedure for the double modification and polymer-polymer conjugation of telechelic polymers is performed through amine-thiol-ene conjugation. Thiolactone end-functionalized polymers are prepared via two different methods, through controlled radical polymerization of a thiolactone-containing initiator, or by modification of available end-functionalized polymers. Next, these different linear polymers are treated with a variety of amine/acrylate-combinations in a one-pot procedure, creating a library of tailored end-functionalized polymers.

Precision Multisegmented Macromolecular Lineups: A Display of Unique Control over Backbone Structure and Functionality.

A practical synthesis of unique, precisely decorated, multisegmented block copolymers was elaborated via amine-thiol-ene conjugation. By mixing the thiolactone-acrylate heterotelechelic precursor polymer with selected amines, a library of multisegmented species was obtained, featuring a high level of control over backbone structure and spatial arrangement of side chain residues. Ranging from glycosylated to amphiphilic materials, these macromolecular lineups have been analyzed by LCxSEC DOSY-NMR, and DLS, revealing the particular properties of these macromolecular structures.

Triazolinediones enable ultrafast and reversible click chemistry for the design of dynamic polymer systems.

With its focus on synthetic reactions that are highly specific and reliable, 'click' chemistry has become a valuable tool for many scientific research areas and applications. Combining the modular, covalently bonded nature of click-chemistry linkages with an ability to reverse these linkages and reuse the constituent reactants in another click reaction, however, is a feature that is not found in most click reactions. Here we show that triazolinedione compounds can be used in click-chemistry applications.

Straightforward RAFT procedure for the synthesis of heterotelechelic poly(acrylamide)s.

Heterotelechelic, hydrophilic polymers with a primary amine and thiol group at the α- and ω-chain end, respectively, are synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization in a straightforward and versatile way and subsequently used for the design of dual-responsive polymer/gold nanohybrids. Therefore, a phthalimido-containing chain transfer agent (CTA) is synthesized and used for the polymerization of the hydrophilic monomers N-isopropylacrylamide (NIPAM) and N,N-dimethylacrylamide (DMA). After polymerization, the trithiocarbonate functionality at the ω-chain end, originating from the CTA, is converted into a thiol upon aminolysis.