Simple One-pot Conversion of Aldehydes and Ketones to Enals
Petr Valenta, Natalie A. Drucker, Jeffrey W. Bode and Patrick J. Walsh*
*P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, Email: pwalshsas.upenn.edu
P. Valenta, N. A. Drucker, J. W. Bode, P. J. Walsh, Org. Lett., 2009, 11, 2117-2119.
A simple and efficient method converts aldehydes into α,β-unsaturated aldehydes with a two-carbon homologation. Hydroboration of ethoxy acetylene with BH3 • SMe2 generates tris(ethoxyvinyl) borane. Transmetalation with diethylzinc, addition to aldehydes or ketones, and acidic workup affords enals or protected derivatives depending on the workup procedure.
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