Variation in the regioselectivity of levulinic acid bromination in ionic liquids

The reaction of levulinic acid and its esters with bromine in ionic liquids results in the formation of 3-bromo derivatives as the major products and not the 5-bromo substituted isomers, which are typically formed in organic solvents. The bromination of levulinic acid in ionic liquids in the presence of urea leads to the formation of 5-broniolevulinic acid. (C) 2009 Elsevier Ltd. All rights reserved.