The effect of thread-like monomer structure on the synthesis of poly[n]catenanes from metallosupramolecular polymers.

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.

Correction: Polycatenanes: synthesis, characterization, and physical understanding.

Correction for 'Polycatenanes: synthesis, characterization, and physical understanding' by Guancen Liu et al., Chem. Soc. Rev., 2022, https://doi.org/10.1039/d2cs00256f.

Polycatenanes: synthesis, characterization, and physical understanding.

Chemical composition and architecture are two key factors that control the physical and material properties of polymers. Some of the more unusual and intriguing polymer architectures are the polycatenanes, which are a class of polymers that contain mechanically interlocked rings. Since the development of high yielding synthetic routes to catenanes, there has been an interest in accessing their polymeric counterparts, primarily on account of the unique conformations and degrees of freedom offered by non-bonded interlocked rings. This has lead to the synthesis of a wide variety of polycatenane architectures and to studies aimed at developing structure-property relationships of these interesting materials. In this review, we provide an overview of the field of polycatenanes, exploring synthesis, architecture, properties, simulation, and modelling, with a specific focus on some of the more recent developments.

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).

Selective synthesis of either enantiomer of an anti-breast cancer agent via a common enantioenriched intermediate.

A stereoselective synthesis of a bioactive triarylmethane is described. Key to the synthesis is a nickel-catalyzed Suzuki-Miyaura coupling which proceeds with retention at the benzylic center. This method is complementary to our previously reported nickel-catalyzed Kumada coupling which proceeds with inversion. Together, the two methods allow for efficient access to either enantiomer of biologically relevant triarylmethanes from a common enantioenriched intermediate.