ORGN 952 |
| Double deprotonation of aliphatic alpha-ketoamides leads to dienediolates which undergo regioselective alkylation to generate (E)-substituted 2-alkyl-2-hydroxybut-3-enamide derivatives. The use of chiral protected iodohydrin electrophiles with prochiral enolates leads to a rare example of electrophile-controlled asymmetric induction, with synthetically useful selectivities (up to 9:1). The structural features of both the enolate and electrophile partners responsible for this phenomenon have been probed and the reaction shows useful generality. The olefins in the 2-alkyl-2-hydroxybut-3-enamide products undergo remarkably general and highly diastereoselective substrate-controlled dihydroxylation, leading to advanced intermediates for the total synthesis of the phospholipase A2 inhibitor Cinatrin B. The key methodological results will be presented alongside the end-game approaches to Cinatrin B.
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New Reactions and Methodology
1:00 PM-5:00 PM, Thursday, 14 September 2006 Moscone Center -- Room 133, Oral
Division of Organic Chemistry |
