CHED 323 |
| Fluorous principles have been applied in developing a recyclable fluorous Rh(II) dinuclear catalyst to promote intramolecular insertion reactions of diazoacetoacetates. Two synthetic pathways have been used to prepare 2,3,5-triperfluorohexylbenzoic acid for conversion to dirhodium(II) tetrakis(perfluoroalkylbenzoate) catalyst. One pathway, adopted from a procedure developed by Endres and Maas, uses protecting group formation of 2,3,5-triiodobenzoic acid by esterification, perfluoroalkylation, and hydrolytic deprotection to produce 2,3,5-perfluorohexylbenzoic acid. The second pathway involves direct perfluoroalkylation of 2,3,5-triiodobenzoic acid. The efficiency and reliability of each pathway will be presented. Syntheses of diazoacetoacetate precursors have been accomplished by decomposition of diketene acetone adduct in the presence of an alcohol to form beta-ketoesters. The alpha-diazo-beta-ketoesters are formed by diazo transfer from 4-acetamidobenzenesulfonyl azide to the beta-ketoesters. The effectiveness of the catalyst to promote intramolecular insertion will be presented. |
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Undergraduate Research Poster Session: Organic Chemistry
2:30 PM-4:30 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Poster
Division of Chemical Education |