Metal induced gel formation from pyridine cored poly(aryl ether) dendrons has been achieved. The gel is successfully utilized as a template for the in situ synthesis of silver nanoparticles (AgNPs) in hydrogel networks without using any external reducing or capping agents for the development of an exceptionally well-ordered AgNP-hybrid hydrogel soft composite.

Organic materials generating pure white light emission have attracted considerable attention in recent times due to their potential applications in lighting and display devices. We have used anthracene carboxylic acid (AnA) and anthracene carbaldehyde (AnC) to generate white light using solvent induced selective self-assembly (SISSA). Mechanistically, SISSA prevents a fast intersystem crossing of the AnC monomer and generates an emissive state from the self-assembled AnC. While AnA emits in the blue region, the self-assembled AnC emits in the greenish yellow region with identical emission intensity. CIE coordinates (0.33, 0.33) of pure white light have been achieved by incorporating orange emitting rhodamine B. More importantly, the pure white light formation has been demonstrated at desired temperatures in both aqueous medium as well as in an agar-agar hydrogel.

In π-conjugated macrocycles, there is a trade-off between the global and local expression of effects such as aromaticity, with the outcome of the trade-off determined by the geometry and aromaticity of the constituent units. Compared with other aromatic rings, the aromatic character of furan is relatively small, and therefore global effects in macrocyclic furans are expected to be more pronounced. Following our introduction of macrocyclic oligofuran, we present the first synthesis of a series of π-conjugated bifuran macrocycles of various ring sizes, from trimer to hexamer, and characterize them using both computational and experimen-tal methods. The properties of macrocyclic oligofurans change considerably with size: The smaller trimer is rigid, weakly emissive and planar as revealed by its single crystal structure, and displays global antiaromaticity. In contrast, the larger pentamer and hexamer are flexible, emissive, have non-planar structures, and exhibit local aromaticity. The results are supported by NICS and ACID calculations that indicate the global antiaromaticity of planar furan macrocycles, and by transient absorption measurements showing sharp absorption band for the trimer and only the internal conversion decay pathway.

Despite decades of investigation, mechanistic details of aqueous permanganate photo-decomposition remain unclear.

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