<i>N</i>‑Arylazetidines: Preparation through Anionic Ring Closure

We report herein an efficient synthesis of diversely substituted <i>N</i>-aryl-2-cyanoazetidines based on an anionic ring-closure reaction. These compounds can be prepared from β-amino alcohols in enantiomerically pure form through a three-step sequence involving (i) copper-catalyzed <i>N</i>-arylation, (ii) <i>N</i>-cyanomethylation of the secondary aniline, and (iii) one-pot mesylation followed by ring closure induced by a base. This high-yielding sequence gives access to azetidines with a predictable and adjustable substitution pattern and also with predictable diastereoselectivity. These compounds are susceptible to multiple further derivatizations through Suzuki coupling or nitrile transformation, thus appearing as valuable new scaffolds for medicinal chemistry. Their rigid shape, featuring an almost planar <i>N</i>-arylamine and a planar four-membered ring, was revealed by both AM1 calculations and X-ray crystallography

Sequential Copper-Catalyzed Alkyne–Azide Cycloaddition and Thiol-Maleimide Addition for the Synthesis of Photo- and/or Electroactive Fullerodendrimers and Cysteine-Functionalized Fullerene Derivatives

In this study, the functionalization of a fullerene building block in a stepwise process by means of the copper-catalyzed alkyne–azide cycloaddition (CuAAC) and thiol-maleimide reactions is reported. Grafting of the fullerene platform with a variety of azido derivatives, including Bodipy, pyrene and ferrocene, was carried out first. These fullerene compounds were then reacted with thiol derivatives to yield sophisticated structures comprising photo- and/or electroactive fullerodendrimers and cysteine-functionalized fullerene assemblies. This strategy, which combines the CuAAC and thiol-maleimide processes, could become more widely adopted in the field of fullerene chemistry