ORGN 11 |
| When treated with cesium hydroxide, allyl or benzyl electrophiles, and cinchonidinium catalysts at -40 °C, protected alpha-hydroxy acyl N-methyl imidazoles are alkylated with high yield and excellent enantioselectivity (79 to >99% ee). These products are converted simply to their corresponding methyl ester adducts, via methyltriflate and sodium methoxide, with no detectable racemization. The process is efficient, direct, and applicable to natural product synthesis. |
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Asymmetric Reactions and Syntheses
8:00 AM-12:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Rm. R06, Oral
Division of Organic Chemistry |