One-pot multicomponent reaction for the synthesis of 2-amino-4-chromenes promoted by 1-methyl imidazoliumiodide [mim]Cl ionic- liq-uid catalyst under solvent-free conditions

A simple, clean, and environmentally benign three-component process for the synthesis of 2-amino-4H-chromenes using [mim]Cl, as an efficient catalyst under solvent-free conditions are described. A wide range of aromatic aldehydes would easily undergo condensations with 1-naphthol and malononitrile under solvent-free conditions in order to afford the desired products of good purity in excellent yields. Taking into account the environmental and economical con-siderations, the protocol presented here has the merits of environmentally benign, simple opera-tion, convenient work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities.