Reversible photoswitching self-assembly of azobenzene-functionalized hyperbranched polyglycerol induced by host-guest chemistry

Conformer-dependent self-assembled metallacycles with photo-reversible response

Discrete, well-defined metallacycles and metallacages with stimuli-responsive behaviors have been largely predominated by the organic donor/metal acceptor paradigm with spontaneous formation of coordination bonds. However, light-driven self-assembly systems usually show relatively low utilization yield of photons and low fatigue resistance. Given that almost no example illustrates the different self-assembly behaviors of antiparallel and parallel conformers in the traditional photochromic diarylethene (DAE) system, here we have for the first time constructed a unique series of photoactive conformer-dependent metallacycles, focusing on the characterization and comparison of self-assembly behavior in different ligand conformers with different di-platinum(ii) acceptors. Their photoswitchable scaffold sizes and shapes are precisely controlled by photochromically separable parallel or anti-parallel conformers via coordination-driven self-assembly. The ap-conformer and closed form provide larger bending angles upon coordination with di-Pt(ii) acceptors into hexagon [6 + 6] or [3 + 3] while the p-conformer only can form smaller polygon cycles. Notably, in contrast with the non-photoactive parallel conformer, the reversible interconversion of anti-parallel ring-open and ring-closed conformer metallacycles can be achieved by alternate irradiation with UV and visible light, respectively, along with a relatively high conversion ratio and good fatigue resistance. This work provides a potential way to construct smart materials for use in sensing, catalysis and drug delivery systems.

Solution processible hyperbranched inverse-vulcanized polymers as new cathode materials in Li–S batteries

Highly soluble inverse-vulcanized hyperbranched polymers were synthesized as cathode-active materials in Li–S batteries.

Hyperbranched polymers: advances from synthesis to applications

This review summarizes the advances in hyperbranched polymers from the viewpoint of structure, click synthesis and functionalization towards their applications in the last decade.

A self-assembled conformational switch: a host–guest stabilized triple stem molecular beacon via a photoactivated and thermal regeneration mode

A novel strategy for construction of a conformational switch is presented with a combination of DNA self-assembly and reversible host–guest inclusion interaction.