Acetic Acid Aldol Reactions in the Presence of Trimethylsilyl Trifluoromethanesulfonate
C. Wade Downey*, Miles W. Johnson, Daniel H. Lawrence, Alan S. Fleisher and Kathryn J. Tracy
*Gottwald Center for the Sciences, University of Richmond, Richmond, Virginia 23173, Email: wdowneyrichmond.edu
C. W. Downey, M. W. Johnson, D. H. Lawrence, A. S. Fleisher, K. J. Tracy, J. Org. Chem., 2010, 75, 5351-5354.
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In the presence of TMSOTf and a trialkylamine base, acetic acid or TMSOAc undergo aldol addition to non-enolizable aldehydes under exceptionally mild conditions. Acidic workup yields the β-hydroxy carboxylic acid. The reaction appears to proceed via trimethylsilyl ester formation, bis-silyl ketene acetal formation, and TMSOTf-catalyzed Mukaiyama aldol addition.
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proposed reaction pathway
Mukaiyama aldol addition, β-hydroxy carboxylic acids