Silver-Catalyzed Skeletal Editing of Benzothiazol-2(3H)-ones and 2-Halogen-Substituted Benzothiazoles as a Rapid Single-Step Approach to Benzo[1,2,3]thiadiazoles

A facile silver(I)-catalyzed reaction of benzothiazol-2(3H)-ones with NaNO2, or using AgNO2 directly, enables a single-step transformation to the corresponding benzo[1,2,3]thiadiazoles in moderate to excellent yields, with wide functional group compatibility. It can also be performed in a one-pot manner from readily available 2-halobenzothiazoles. This intriguing transformation involving an atom replacement in the S,N-heteroarene ring thus provides rapid access to isobenzothiadiazoles (while avoiding the usage of unstable precursors) and also expands the toolbox of modern skeletal editing reactions.

L-Cysteine/AgNO2 low molecular weight gelators: self-assembly and suppression of MCF-7 breast cancer cells

We report a new supramolecular hydrogel based on simple amino acids and silver salt compounds with low molecular weights. The in situ formation of silver nanoparticles during the self-assembly process endows the hydrogel with high cytotoxicity towards adenocarcinoma breast cells but no toxic effects towards embryonic fibroblasts.

Biaryl synthesis with arenediazonium salts: cross-coupling, CH-arylation and annulation reactions

The rich legacy of arenediazonium salts in the synthesis of unsymmetrical biaryls, built around the seminal works of Pschorr, Gomberg and Bachmann more than a century ago, continues to make important contributions at various evolutionary stages of modern biaryl synthesis. Based on in-depth mechanistic analysis and design of novel pathways and reaction conditions, the scope of biaryl synthesis with arenediazonium salts has enormously expanded in recent years through applications of transition metal/photoredox-catalysed cross-coupling, thermal/photosensitized radical chain CH-arylation of (hetero)arenes and arylative radical annulation reactions with alkynes. These recent developments have provided facile synthetic access to a wide variety of unsymmetrical biaryls of pharmaceutical, agrochemical and optoelectronic importance with green scale-up options and created opportunities for late-stage modification of peptides, nucleosides, carbon nanotubes and electrodes, the details of which are captured in this review.