ORGN 18 |
| Carbonyl compounds are ubiquitously present in nature and therefore constitute important building blocks for organic chemists in life science. The ability to functionalize carbonyl compounds is well known and the aldol and Michael reactions are textbook examples of a- and b- functionalizations, respectively. The asymmetric versions of carbonyl functionalizations are particularly well-suited for organocatalysis, which presents a benign and “user-friendly” approach to enantioselective catalysis. Herein, we will present studies of the a- and b- functionalization of aldehydes. Furthermore, a novel extension of the protocol leading to g-substituted products is presented (Figure 1). Mechanistic considerations will be presented to support the experimental results. The usefulness of the obtained products is further demonstrated by the application of b-functionalized adducts in several different one-pot reactions leading to a diverse range of highly substituted carbocycles with multiple stereocenters. (Elec = electrophile, Nuc = nucleophile)
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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 |
