An Ionic Liquid-Mediated Route to Cerium(III) Bromide Solvates

A novel synthetic route to a series of cerium bromide solvates is reported. The combination of bulk cerium bromide and the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide results in a precursor paste that enhances the solubility of the cerium(III)bromide moiety in a number of donor solvents. Crystallization from these solvents has resulted in the isolation and characterization of CeBr₃(THF)₄ (2), CeBr₃(2-Me-THF)₄ (3), and CeBr₃(MeCN)₅·MeCN (4). Additionally, 2 is shown to be an efficient precursor for the new species CeBr₃(py)₄ (5) and CeBr₃(bipy)(py)₃ (6).