Synthesis of sydnonimines from sydnones and their use for bioorthogonal release of isocyanates in cells.

In this article, we report the synthesis of sydnonimines from sydnones and their use as dipoles for fast click-and-release reactions. The process relies on nucleophilic aromatic substitution of aliphatic and aromatic amines with triflated sydnones. This new methodology allowed the preparation of functionalised sydnonimine probes that are otherwise difficult to prepare. These probes were then used to release a drug and a fluorescent aromatic isocyanate inside living cells.

Nickel-Catalyzed Asymmetric Reductive Diarylation of Vinylarenes.

A nickel-catalyzed asymmetric diarylation reaction of vinylarenes enables the preparation of chiral α,α,ß-triarylated ethane scaffolds, which exist in a number of biologically active molecules. The use of reducing conditions with aryl bromides as coupling partners obviates the need for stoichiometric organometallic reagents and tolerates a broad range of functional groups. The application of an N-oxyl radical as a ligand to a nickel catalyst represents a novel approach to facilitate nickel-catalyzed cross-coupling reactions.