IEC 184 |
| Jin Qian1, Michael Timko2, Jefferson W. Tester2, Jeffrey I. Steinfeld3, Bozena Winnik4, and Brian Buckley4. (1) Laboratory for Energy and the Environment, Massachusetts Institute of Technology, Cambridge, MA 02139, (2) Lab for Energy and the Environment and Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, (3) Lab for Energy and the Environment and Department of Chemistry, Massachusetts Institute of Technology, 2-221 M.I.T, Cambridge, MA 02139, (4) Environmental and Occupational Health Sciences Institute, Rutgers University, 170 Frelinghuysen Rd., Piscataway, NJ 08854 |
| Green synthetic chemistry is more than simply replacing hazardous solvents or reagents with less toxic ones. In addition to being environmentally friendly, the reaction media should be chemically efficient (highly selective with acceptablly fast kinetics) and economically viable. Due to its high density and non-toxicity, at moderate pressure (less than 150 bar) and near ambient temperature, compressed liquid and supercritical carbon dioxide (scCO2) is a promising green solvent for organic synthesis. One of the major technical obstacles to the widespread industrial implementation of liquid or scCO2 as a solvent for chemical synthesis is the fact that very few reactions have been shown to proceed with enhanced rate or selectivity as compared to their behavior in conventional organic solvent and the solubility of many industrially important reagents and products is very low in CO2. In this study, the kinetics of the Diels-Alder reaction of the dienophile N-ethylmaleimide with the diene 9-hydroxymethylanthracene is followed in situ by disappearance of 9-hydroxymethylanthracene at 379 nm by UV-Vis Spectrophotometry. The adduct in the reaction was identified by reversed-phase HPLC with MS/MS detection utilizing an atmospheric pressure chemical ionization interface. We have found that scCO2 increases the rate of this reaction as compared to traditional organic solvents. For instance, in scCO2 our measured rate is 23 times faster than that reported for the reaction in acetonitrile. Our results suggest that carefully selected reactions can benefit from using scCO2 as a solvent. |
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General Poster Session
5:00 PM-7:00 PM, Tuesday, March 25, 2003 Convention Center -- Hall G, Poster
Division of Industrial and Engineering Chemistry |