Proline-catalyzed asymmetric aldol reactions between ketones and alpha-unsubstituted aldehydes.
[reaction: see text] With this communication we extend the methodology of proline-catalyzed direct asymmetric aldol reactions to include alpha-unsubstituted aldehydes as acceptors. This important aldehyde class gives the corresponding aldols in 22-77% yield and up to 95% ee when the reactions are performed in pure acetone or in ketone/chloroform mixtures. On the basis of these results we have developed a concise new synthesis of (S)-ipsenol.
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Departments of Chemistry and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA. blist@scripps.edu
Pojarliev
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Castello
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D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D011392:Proline / Q000737:chemistry*; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D007659:Ketones; C424142:ipsenol; D011392:Proline