Nickel-Imidazolium Low Transition Temperature Mixtures with Lewis-Acidic Character

Molecules. 2023 Aug 30;28(17):6338. doi: 10.3390/molecules28176338.

Abstract

Low transition temperature mixtures (LTTMs) are a new generation of solvents that have found extensive application in organic synthesis. The interactions between the components often generate highly activated, catalytically active species, thus opening the possibility of using LTTMs as catalysts, rather than solvents. In this work, we introduce a nickel-based imidazolium LTTM, study its thermal behavior and explore its catalytic activity in the solvent-free allylation of heterocycles with allylic alcohols. This system is effective in this reaction, affording the corresponding products in excellent yield without the need for additional purifications, thus resulting in a very environmentally friendly protocol.

Keywords: allylic alcohols; imidazolium salts; low transition temperature mixtures; sustainable chemistry; tetrachloronickelates.