We report a versatile Cu-catalyzed multicomponent polymerization (MCP) technique that enables the synthesis of high-molecular-weight, defect-free poly(N-sulfonylamidines) from monomers of diynes, sulfonyl azides, and diamines. Through a series of optimizations, we discovered that the addition of excess triethylamine and the use of N,N'-dimethylformamide as a solvent are key factors to ensure efficient MCP. Formation of cyclic polyamidines was a side reaction during polymerization, but it was readily controlled by using diynes or diamines with long or rigid moieties. In addition, this polymerization is highly selective for three-component reactions over click reactions. The combination of the above factors enables the synthesis of high-molecular-weight polymers, which was challenging in previous MCPs. All three kinds of monomers (diynes, sulfonyl azides, and diamines) are readily accessible and stable under the reaction conditions, with various monomers undergoing successful polymerization regardless of their steric and electronic properties. Thus, we synthesized various high-molecular-weight, defect-free polyamidines from a broad range of monomers while overcoming the limitations of previous MCPs, such as low conversion and defects in the polymer structures.

This manuscript is dedicated to Professor Mitsuo Sawamoto's outstanding achievements in polymer chemistry and recognizes his recent retirement from 40 years of exceptional service to Kyoto University.To address this challenge and provide insight into photo-CRP processes, a recently developed in situ NMR spectroscopy method is utilized to evaluate temporal control for a selection of widely studied photo-CRP processes (see Fig. 1 and Supplementary Information Figure S1 for a Additional supporting information may be found in the online version of this article.

The development and application of a novel endo furan-protected maleimide building block is reported. The endo isomer undergoes deprotection at temperatures ~50 °C below the exo derivative. This enables a simple and powerful approach to quantitatively and selectively introduce functional maleimide groups via temperature modulation.

Using a grafting-through strategy, brush polymers containing semiconducting polyene backbones were efficiently synthesized by cyclopolymerization for the first time. Macromonomers containing poly(l-lactide) and poly(ε-caprolactone), prepared by living ring-opening polymerization, were polymerized using the Grubbs–Hoveyda catalyst to produce high molecular weight (>0.5 M Da) brush polymers. The brush polymers underwent a unique coil-to-rod transition during the aging of the polymer solution, and this conformational change was supported by UV–vis and size-exclusion chromatography (SEC)–viscometry analysis. In addition, the extended conformation of single chains of the brush polymers could be visualized by atomic force microscopy.

1D nanocaterpillar structures were spontaneously formed during the synthesis of fully conjugated poly(2,5-dihexyloxy-1,4-phenylene)-block-polythiophene due to the strong π-π interactions between the polythiophene blocks. With the elongation of the polythiophene block, nanostructures evolved from nanospheres to nanocaterpillars and their length and height increased with good control.