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We report the first heterotelechelic helical poly(methacrylamide) (PMAc) bearing orthogonal supramolecular binding sites on its chain-ends synthesized through a combination of reversible addition–fragmentation chain-transfer (RAFT) polymerization and thiol–bromo “click” chemistry. The heterotelechelic PMAc was assembled with two monotelechelic polymers featuring different secondary structures, namely a coil-like poly(styrene) and a helical poly(isocyanide), resulting in the formation of a coil–helix–helix supramolecular triblock copolymer through orthogonal metal coordination and hydrogen bonding interactions. Triblock assembly was confirmed through 1 H NMR spectroscopy, isothermal titration calorimetry (ITC) and viscometry. The individual polymer blocks retained their secondary structures in the final triblock copolymer, as evidenced by circular dichroism (CD) spectroscopy. Our synthetic strategy expands the toolbox of triblock copolymers featuring structural motifs similar to the ones found in proteins and provides the potential for the development of other complex multifunctional polymeric ensembles.
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Homochiral Helical Poly(thiophene)s Accessed via Living Catalyst‐Transfer Polymerization
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.
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- Award ID(s):
- 2203929
- PAR ID:
- 10628077
- Publisher / Repository:
- Wiley VCH
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 64
- Issue:
- 19
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/anie.202502104
