Wednesday, June 25, 2008 Congressional Room (Capital Hilton) 99
A Mild and Environmentally Friendly α-Bromination of Ketones in Ionic Liquid Using 1,3-Dibromo-5,5-Dimethylhydantoin(DBDMH) and UHP in H2O
Soon-Uk Chang and Jong Chan Lee. Chung-Ang University, Seoul, South Korea
Evolution of environmentally friendly synthesis is a paramount goal of the present day organic chemistry. In recent years, ionic liquids have been acknowledged as green alternatives to the toxic and volatile organic solvents for various chemical reactions. Bromination of organic compounds is one of the important synthetic implement in organic syntheses. The drawbacks of many known bromination methods associated with the use of organic solvents and toxic reagents lead us to develop more greener bromination systems. In this context, a new environmentlly friendly bromination protocols has been developed. In our work, an efficient and selective a-bromination of ketones by use of 1,3-dibromo-5,5-dimethylhydantoin(DBDMH) and UHP in H2O in ionic liquid at 50-60°C is smoothly achieved. Bromination with 1,3-dibromo-5,5-dimethylhydantoin(DBDMH) as a source of bromine cation have been accomplished a mild and environmentally benign UHP in H2O and provides selectively bromination in excellent yields in the presence of catalytic Ionic liquids.