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Crown-ether functionalized poly(p-phenylenevinylene) (red) and cationic dibenzyl amine chain-end functionalized poly(styrene) (blue) were synthesized and assembled into optically active, pH responsive, and semi-crystalline bottlebrush copolymers. 

Abstract Synthetic helical polymers form compact, ordered, and inherently chiral structures, enabling their uses in biomimetic applications as well as catalysis. A challenge in using synthetic helical polymers, however, is their tendency to be sensitive to pH and the presence of nucleophiles, Lewis‐acids, or metal ions. We report a strategy to overcome these shortcomings by adapting catalyst‐transfer polymerization, a living chain‐growth polymerization typically used to access linear conjugated polymers, for the synthesis of helical poly(thiophene)s. We demonstrate that the helical poly(thiophene)s can be synthesized with a single helicity, incorporated into block copolymers, and functionalized at the chain‐ends, enabling further conjugation and functionalization. The helical poly(thiophene)s are stable to a variety of conditions, providing benefits over other helical polymers which contain sensitive imine or carbonyl‐based functional groups. We anticipate that the ability to access homochiral, heterotelechelic helical conjugated polymers and copolymers will enable new uses of these materials in optoelectronics as well as in applications for mimicking biomacromolecules and other polymers with precisely defined sequences. 

We report poly(isocyanide)-based random copolymers (co-PIC) featuring alkoxycarbonyl-based side-chains synthesized via the metal-catalyzed controlled polymerization of chiral and achiral isocyanide monomers. The pyridine-functionalized achiral monomer provides functional sites while the chiral monomer drives the formation of a one-handed preferred helix. The side-chain functionalized helical polymer undergoes self-assembly with palladated pincer ligands, as evidenced by 1H NMR and UV-Vis spectroscopies. Circular dichroism (CD) spectroscopy confirms that the side-chain self-assembly does not affect the backbone helicity. We construct supramolecular helical brush copolymers via the metal coordination of the co-PIC backbone with telechelic poly(styrene)s. 1H NMR and UV-Vis spectroscopies confirm the metal coordination, and CD measurements suggest that the backbone retains its helical conformation. Additionally, viscometry measurements verify the formation of high molecular weight polymers while dynamic light scattering confirms the increasing hydrodynamic radii of the resulting supramolecular brush copolymers. Our methodology constructs complex 3D materials with fully synthetic, secondary structure containing building blocks. We view this as a platform for building architecturally controlled 3D supramolecular materials with high degrees of complexity. 

Novel antiviral nanotherapeutics, which may inactivate the virus and block it from entering host cells, represent an important challenge to face viral global health emergencies around the world. Using a combination of bioorthogonal copper-catalyzed 1,3-dipolar alkyne/azide cycloaddition (CuAAC) and photoinitiated thiol–ene coupling, monofunctional and bifunctional peptidodendrimer conjugates were obtained. The conjugates are biocompatible and demonstrate no toxicity to cells at biologically relevant concentrations. Furthermore, the orthogonal addition of multiple copies of two different antiviral peptides on the surface of a single dendrimer allowed the resulting bioconjugates to inhibit Herpes simplex virus type 1 at both the early and the late stages of the infection process. The presented work builds on further improving this attractive design to obtain a new class of therapeutics.