Catalytic Asymmetric Synthesis of α-Alkylidene-β-hydroxy Esters via Dynamic Kinetic Asymmetric Transformation Involving Ba-Catalyzed Direct Aldol Reaction
Akitake Yamaguchi, Shigeki Matsunaga* and Masakatsu Shibasaki*
*Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan, Email: smatsunamol.f.u-tokyo.ac.jp, mshibasamol.f.u-tokyo.ac.jp
A. Yamaguchi, S. Matsunaga, M. Shibasaki, J. Am. Chem. Soc., 2009, 131, 10842-10843.
DOI: 10.1021/ja904575e (free Supporting Information)
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A Ba-catalyzed dynamic kinetic asymmetric transformation (DYKAT) involving a direct aldol/retro-aldol reaction of a β,γ-unsaturated ester with various aldehydes and an isomerization under simple proton-transfer conditions allows the synthesis of α-alkylidene-β-hydroxy esters with high enantio- and regioselectivity.
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proposed reaction pathway