Coordination-based ionic liquids (IL) have attracted extensive fascination in past few years

for their exceptional physical properties and potential applications in green separation

catalysis and electrolytes. Among them

chelate ILs are advantageous due to their enhanced multiple-site chelating interactions between metals and ligands. Based on positions of metallic components in molecules

chelate ILs can be divided into four classes

i.e.

cation

anion

cation-anion and neutral chelate ILs. The synthesis

physical properties and applications of chelate ILs were reviewed from recent publications. Present issues

challenges and future research directions were also discussed.