The main-chain poly[ n ]catenane consists of a series of interlocked rings that resemble a macroscopic chain-link structure. Recently, the synthesis of such intriguing polymers was reported via a metallosupramolecular polymer (MSP) template that consists of alternating units of macrocyclic and linear thread-like monomers. Ring closure of the thread components has been shown to yield a mixture of cyclic, linear, and branched poly[ n ]catenanes. Reported herein are studies aimed at accessing new poly[ n ]catenanes via this approach and exploring the effect the thread-like monomer structure has on the poly[ n ]catenane synthesis. Specifically, the effect of the size of the aromatic linker and alkenyl chains of the thread-like monomer is investigated. Three new poly[ n ]catenanes (with different ring sizes) were prepared using the MSP approach and the results show that tailoring the structure of the thread-like monomer can allow the selective synthesis of branched poly[ n ]catenanes.
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Effect of metallosupramolecular polymer concentration on the synthesis of poly[ n ]catenanes
Poly[ n ]catenanes are a class of polymers that are composed entirely of interlocked rings. One synthetic route to these polymers involves the formation of a metallosupramolecular polymer (MSP) that consists of alternating units of macrocyclic and linear thread components. Ring closure of the thread components has been shown to yield a mixture of cyclic, linear, and branched poly[ n ]catenanes. Reported herein are investigations into this synthetic methodology, with a focus on a more detailed understanding of the crude product distribution and how the concentration of the MSP during the ring closing reaction impacts the resulting poly[ n ]catenanes. In addition to a better understanding of the molecular products obtained in these reactions, the results show that the concentration of the reaction can be used to tune the size and type of poly[ n ]catenanes accessed. At low concentrations the interlocked product distribution is limited to primarily oligomeric and small cyclic catenanes . However, the same reaction at increased concentration can yield branched poly[ n ]catenanes with an ca. 21 kg mol −1 , with evidence of structures containing as many as 640 interlocked rings (1000 kg mol −1 ).
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- Award ID(s):
- 1903603
- NSF-PAR ID:
- 10232656
- Date Published:
- Journal Name:
- Chemical Science
- ISSN:
- 2041-6520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Tz denotes a 1,2,3‐triazole moiety replacing one phenylene ring in the [n]CPP backbone). -
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ABSTRACT This work investigates effects of poly(
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1SC02450G
