Densely functionalized alkenes are often utilized as excellent tools for further functionalization of molecules. Recent progress in their synthesis includes nucleophilic addition to vinylbenziodoxolones (VBX) and vinylbenziodoxoles (VBO) to reach alkenes with complete regio- and stereocontrol. In this work, we leverage the inherent properties of mechanochemistry to enable an efficient transition metal-free one-pot route to 1,2-heteroatom-substituted (Z)-alkenes directly from ethynylbenziodoxol(on)es (EBX/EBO), avoiding the isolation of VBX/VBO. We demonstrate a high-yielding synthesis of a large variety of N/O/S-VBX reagents, which, combined with a telescoped nucleophilic addition, delivers a wide range of novel, complex (Z)-alkenes. This one-pot strategy would be challenging to develop in solution due to a mismatch in reaction solvents, and the unique mechanochemical activation offered by solventless, solid-state mixing also enables formation of products whose synthesis is inefficient with solvent-based methods.

Although functionalized cyclopropenes have found uses in many applications, their synthesis has been severely limited. Now, a hypervalent iodine reagent, in conjunction with gold catalysis, has been utilized to control their reactivity, allowing efficient formation of cyclopropenyl alkynes/alkenes.

The combination of mechanochemistry and hypervalent iodine chemistry has rarely been reported, despite the numerous advantages offered by this enabling technology. With this in mind, this study addresses the key issue of transforming hypervalent iodine-mediated, solution-based reactions into the mechanochemical realm, accompanied by benchmarking and sustainability studies of the different types of reactions. Interestingly, several reagents displayed quite different reactivity and regioselectivity under mechanochemical conditions.

Our group has reported several one-pot protocols for the synthesis of diaryliodonium salts, which have been recognized as attractive multi-purpose reagents in areas ranging from organic synthesis to materials chemistry. Over the years, we have identified limitations in the published protocols concerning synthesis of mixed electron-rich and electron-poor, as well as highly electron-poor diaryliodonium salts, as the corresponding starting materials are either too reactive or too unreactive. In this update, we discuss the underlying limitations concerning the stability and reactivity of the involved reagents and provide strategies to overcome these challenges through updated synthetic protocols. 

N- and O-arylated compounds are prevalent in pharmaceuticals and materials, and efficient approaches for their synthesis are important. Herein, we present an efficient protocol for the diarylation of aliphatic amines and water with two structurally different aryl groups in one single step, yielding highly functionalized diaryl amines and ethers. We describe the synthesis of the required diaryliodonium salts and detail the procedure for the diarylation. The protocol is limited to use of unhindered amines and diaryliodonium salts with certain substituents.