Tuning vibration-induced emission through macrocyclization and catenation.

In order to investigate the effect of macrocyclization and catenation on the regulation of vibration-induced emission (VIE), the typical VIE luminogen 9,14-diphenyl-9,14-dihydrodibenzo[a, c]phenazine (DPAC) was introduced into the skeleton of a macrocycle and corresponding [2]catenane to evaluate their dynamic relaxation processes. As investigated in detail by femtosecond transient absorption (TA) spectra, the resultant VIE systems revealed precisely tunable emissions upon changing the solvent viscosity, highlighting the key effect of the formation of [2]catenane. Notably, the introduction of an additional pillar[5]arene macrocycle featuring unique planar chirality endows the resultant chiral VIE-active [2]catenane with attractive circularly polarized luminescence in different states.

Extended phenothiazines: synthesis, photophysical and redox properties, and efficient photocatalytic oxidative coupling of amines.

Herein we successfully developed a ring-fusion approach to extend the conjugation length of phenothiazines and synthesized a series of novel extended phenothiazines 1-5. The intriguing π-conjugation length-dependent photophysical and redox properties of 1-5, and their photocatalytic performance towards visible-light-driven oxidative coupling reactions of amines were systematically investigated. The results indicated that this series of extended phenothiazines exhibited continuous red shifts of light absorption with increasing numbers of fused rings.

Recent advances and perspectives on supramolecular radical cages.

Supramolecular radical chemistry has been emerging as a cutting-edge interdisciplinary field of traditional supramolecular chemistry and radical chemistry in recent years. The purpose of such a fundamental research field is to combine traditional supramolecular chemistry and radical chemistry together, and take the benefit of both to eventually create new molecules and materials. Recently, supramolecular radical cages have been becoming one of the most frontier and challenging research focuses in the field of supramolecular chemistry.

Palladium/Xu-Phos-catalyzed asymmetric carboamination towards isoxazolidines and pyrrolidines.

An efficient palladium-catalyzed enantioselective carboamination reaction of -Boc--homoallyl-hydroxylamines and -Boc-pent-4-enylamines with aryl or alkenyl bromides was developed, delivering various substituted isoxazolidines and pyrrolidines in good yields with up to 97% ee. The reaction features mild conditions, general substrate scope and scalability. The obtained products can be transformed into chiral 1,3-aminoalcohol derivatives without erosion of chirality.

Hierarchical self-assembly of discrete bis-[2]pseudorotaxane metallacycle with bis-pillar[5]arene host-guest interactions and their redox-responsive behaviors.

A discrete rhomboidal metallacycle R functionalized with bis-[2]pseudorotaxane of [Cu(phenanthroline)] derivatives was successfully synthesized coordination-driven self-assembly. Furthermore, the host-guest complexation of such a bis-[2]pseudorotaxane metallacycle with a bis-pillar[5]arene (bisP5) allowed for the formation of a new family of cross-linked supramolecular polymers R⊃(bisP5), which displayed interesting redox-responsive properties. By taking advantage of the substantial structural differences between the coordination geometries of [Cu(phenanthroline)] and [Cu(phenanthroline)], the weight-average diffusion coefficients of the supramolecular polymer were adjusted through changing the redox state of the Cu(i)/Cu(ii) complexes.