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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. 

Abstract The fabrication of truly hierarchically folded single‐chain polymeric nanoparticles with primary, secondary, and defined 3D architecture is still an unfulfilled goal. In this contribution, a polymer is reported that folds into a well‐defined 3D structure from a synthetic sheet‐helix block copolymer. The sheet‐like poly(p‐phenylene vinylene) (PPV) block is synthesized via the ring‐opening metathesis polymerization of a thymine‐bearing dialkoxy‐substituted [2.2]paracyclophane‐1,9‐diene. The PPV block is terminated with a Pd complex using a Pd‐containing chain‐terminating agent. The terminal Pd complex catalyzes the polymerization of isocyanide monomers with side‐chains containing either a chiral menthol or an achiral diaminopyridine resulting in the formation of a helical poly(isocyanide) (PIC) random copolymer. The PIC side‐chains are capable of engaging in complementary hydrogen‐bonding with thymine units along the PPV block resulting in the folding of the two secondary structural domains into a well‐defined 3D structure. The folding and unfolding of the polymer in both chloroform and THF are monitored using dynamic light scattering and NMR spectroscopy. This work is the first example of a hierarchically folded synthetic polymer featuring a defined 3D structure achieved by using two different polymer backbones with two distinct secondary structures.