ORGN 25 |
| In the last few years, organocatalytic reactions have emerged as powerful tools for the preparation of optically active compounds. Among these is the aldol reaction, which constitutes one of the most commonly used methods for the formation of carbon-carbon bonds. Within our group aldolase type I antibodies have been used to kinetically resolve racemic mixtures of aldols derived from unsymmetrical ketone as well as enone donors with high enantioselectivity. Our attention was then driven towards aldols derived from ynones. Only a very limited number of catalytic asymmetric aldol reactions are known to access these compounds despite their enormous synthetic potential. As an alternative to catalytic antibodies, we have now screened a large number of proline-based catalysts and have identified suitable organocatalysts which are able to deliver structurally diverse β-hydroxyynones in good yields and high levels of diastereo- and enantiocontrol. These adducts could be further functionalised into dihydropyranones and furanones without loss of selectivity.
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Asymmetric Reactions and Syntheses
8:00 AM-12:20 PM, Sunday, 10 September 2006 Moscone Center -- Room 131, Oral
Division of Organic Chemistry |
