A [P44414][Cl]-NaCl-H2O ionic liquid-based aqueous biphasic system shows promising results for the separation of cobalt(II) and nickel(II) by homogeneous liquid-liquid extraction. The extracting phase consists of a hydrophilic ionic liquid that is salted-out by sodium chloride, indicating that there is no need for using hydrophobic ionic liquids.

An overview of the latest developments (2016–August 2020) in the metal-free synthesis of non-benzo-fused N-functionalized and NH-1,2,3-triazoles is provided in this feature article.

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A metal-free three-step synthesis toward functionalized 1-methyleneisoquinolines from readily available substrates is reported. First, acetal-containing 1,2,3-triazoles were prepared via a high-yielding triazolization reaction and quantitatively converted into triazolo­[5,1-a]­isoquinolines. Next, the acid-promoted ring opening of these fused triazoles was studied in order to obtain coupling to a diverse scope of nucleophiles, including carbon nucleophiles such as veratrole. By means of non-nucleophilic strong acids under anhydrous conditions, a series of unprecedented isoquinolines and imidazo­[5,1-a]­isoquinolines was synthesized.

The development of metal‐free syntheses toward 1,2,3‐triazoles has been a burgeoning research area throughout the past decade. Despite the numerous advances, the scarceness of methods for the preparation of 1,5‐disubstituted 1,2,3‐triazoles from readily available substrates remained a challenge that was addressed by our group in 2016. A metal‐free three‐component reaction, which we have dubbed the triazolization reaction, was established for the rapid synthesis of 1,5‐disubstituted, fully functionalized and NH‐1,2,3‐triazoles. This novel approach stands out because it utilizes widely available starting materials, namely primary amines and enolizable ketones. Furthermore, the broad substrate scope is a major advantage, and was further expanded by the number of modified protocols that have been reported. Triazolization products have successfully found utility as intermediates in various synthetic transformations, and were the subject of a few interesting biological activity studies.