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Award ID contains: 2104554

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  1. Abstract Living cationic ring‐opening polymerization accompanied by isomerization of cyclic imino ethers is performed at high temperatures that provide access to the synthesis of self‐organizable systems in their isotropic melt or solution state. This Perspective discusses fundamental mechanistic principles of this polymerization and bridges with the polymerization of dendronized cyclic iminoethers forming polymers that self‐organize soft Frank–Kasper and quasicrystal periodic and quasiperiodic arrays. These two fields represent frontiers in macromolecular and supramolecular science. A brief discussion of the impact of this polymerization on biomaterials and how it impacted contemporary mechanistic investigations is also made. Expected impacts via future synthetic developments and mechanistic investigations are discussed. 
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  2. Abstract DMSO, an interesting solvent for copper‐catalyzed living radical polymerization (LRP) mediated by disproportionation, does not exhibit the greatest disproportionation of Cu(I)X into Cu(0) and Cu(II)X2. Under suitable conditions, DMSO provides 100% conversion and absence of termination, facilitating the development of complex‐architecture methodologies by living and immortal polymerizations. The mechanism yielding this level of precision is being investigated. Here we compare Cu(0)‐wire‐catalyzed LRP of methyl acrylate mediated by disproportionating ligands tris(2‐dimethylaminoethyl)amine, Me6‐TREN, tris(2‐aminoethyl)amine, TREN, and Me6‐TREN/TREN = 1/1 in presence of eight disproportionating solvents, some more efficient than DMSO in disproportionation. Unexpectedly, we observed that all solvents increased the rate of polymerization when monomer concentration decreased. This reversed trend from that of conventional LRPs demonstrates catalytic effect for disproportionating solvents. Above a certain concentration, the classic concentration‐rate dependence was observed. The external order of reaction of the apparent rate constant of propagation,kpappon solvent concentration demonstrated the highest order of reaction for the least disproportionating DMSO. Of all solvents investigated, DMSO has the highest ability to stabilize Cu(0) nanoparticles and therefore, yields the highest activity of Cu(0) nanoparticles rather than their greatest concentration. The implications of the catalytic effect of solvent in this and other reactions were discussed. 
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  3. Abstract Homochiral helical self‐organizations provide some of the most fundamental architectures of biological macromolecules and of their co‐assemblies although they were first discovered and elucidated only during the early 1950. Helical synthetic covalent macromolecules started to be discovered soon after and were followed by supramolecular macromolecules and their co‐assemblies few decades later. This perspective will provide a brief historical development of chiral helical self‐organizations in biology and in supramolecular chemistry. Helical covalent and supramolecular macromolecules self‐organize and co‐organize helical supramolecular columns and spherical helices that can generate complex liquid crystals, crystals including Frank‐Kasper phases, and quasicrystals. The design of new functions based on synthetic helical assemblies will also be discussed. Personal events from the life of scientists contributing to these developments are also briefly mentioned. 
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