ORGN 667 |
| 2-Butadienylphenacyloxazolones under an intramolecular Diels-Alder reaction to give a tetracyclic species that is a useful intermediate for the synthesis of phenanthridone alkaloids. A problem with the synthesis is the lack of a good synthesis for 2-oxazolone, which is not commercially available. we have shown that sulfuryl chloride reaction with 2-oxazolidinone leads to two chlorooxazolidiones, which are separable. They react differently upon heating, but low yields of oxazolone can be obtained. Better results are obtained by simply heating the crude chlorinated products. The overall yield of oxazolone is no better than other literature reports, but this method avoids the use of chlorine gas, and is manageable on a lab scale. apart from the intramolecular Diels-Alder route to phenanthridone alkaloids, we are also exploring the intermolecular Diels-Alder reaction with unsymmetrical dienes, particularly those that can be used in the synthesis of alkaloids. |
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New Reactions and Methodology
1:00 PM-5:00 PM, Wednesday, 16 March 2005 Convention Center -- Ballroom 20 C-D, Oral
Division of Organic Chemistry |
