Phosphonate-Functionalized Polycarbonates Synthesis through Ring-Opening Polymerization and Alternative Approaches.

Well-defined phosphonate-functionalized polycarbonate with low dispersity (Ð = 1.22) was synthesized using organocatalyzed ring-opening polymerization (ROP) of novel phosphonate-based cyclic monomers. Copolymerization was also performed to access different structures of phosphonate-containing polycarbonates (PC). Furthermore, phosphonate-functionalized PC was successfully synthesized using a combination of ROP and post-modification reaction.

Photolabile Well-Defined Polystyrene Grafted on Silica Nanoparticle via Nitroxide-Mediated Polymerization (NMP).

Herein, the synthesis of a novel nitroxide-mediated polymerization (NMP) initiator bearing a photolabile ortho-nitrobenzyl (oNB) group allowing surface-initiated NMP preparation of well-defined photoresponsive polystyrene grafted on silica nanoparticles is described. The photocleavable and photoresponsive properties of the prepared materials are demonstrated using small angle X-ray scattering (SAXS) characterization.

Azlactone-based heterobifunctional linkers with orthogonal clickable groups: efficient tools for bioconjugation with complete atom economy.

We report the efficient synthesis of a series of new azlactone-based heterofunctional linkers bearing two orthogonal clickable groups that proceed with full atom economy. These new linkers comprise an azlactone (oxazolone) group that quickly reacts with amino groups in biologically relevant medium without byproduct elimination and a (bio)orthogonal handle which further undergoes facile and selective click reactions such as thiol-ene coupling, Diels-Alder or azide-alkyne cycloadditions. As an example, the application of this methodology to lysozyme PEGylation in aqueous medium is described.

Tuning the Molar Composition of "Charge-Shifting" Cationic Copolymers Based on 2-(N,N-Dimethylamino)Ethyl Acrylate and 2-(tert-Boc-Amino)Ethyl Acrylate.

Copolymers of 2-(N,N-dimethylamino)ethyl acrylate (DMAEA) and 2-(tert-Boc-amino)ethyl acrylate (tBocAEA) are synthesized by reversible addition-fragmentation chain transfer polymerization in a controlled manner with defined molar masses and narrow molar masses distributions (Ð ≤ 1.17). Molar compositions of the P(DMAEA-co-tBocAEA) copolymers are assessed by means of 1 H NMR. A complete screening in molar composition is studied from 0% of DMAEA to 100% of DMAEA. Reactivity ratios of both comonomers are determined by the extended Kelen-Tüdos method (r DMAEA = 0.81 and rtBocAEA = 0.99).

Amine-reactive polymers synthesized by RAFT polymerization using an azlactone functional trithiocarbonate RAFT agent.

A new azlactone-derived trithiocarbonate is prepared and used as a chain-transfer agent to mediate the reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene, ethyl acrylate, and N-isopropyl acrylamide. Well-defined polymers with controlled molecular weights (M(n) = 1000-7000 g mol(-1) ) and narrow molecular weight distributions (PDI = 1.05-1.10) are thus obtained that retain the azlactone functionality at the chain end. The ability of the resulting end-functionalized polymers to react quantitatively at room temperature with a stoichiometric amount of amino groups with retention of the thiocarbonylthio moiety is ascertained by using 4-fluorobenzylamine and allylamine.