General, Robust, and Stereocomplementary Preparation of α,β-Disubstituted α,β-Unsaturated Esters
Hidefumi Nakatsuji, Hiroshi Nishikado, Kanako Ueno and Yoo Tanabe*
*Department of Chemistry, School of Science and Technology,
Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan, Email: tanabekwansei.ac.jp
H. Nakatsuji, H. Nishikado, K. Ueno, Y. Tanabe, Org. Lett., 2009, 11, 4258-4261.
DOI: 10.1021/ol9013359
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Abstract
An (E)- and (Z)-stereocomplementary preparative method for α,β-disubstituted α,β-unsaturated esters is performed via three general and robust reaction sequences: Ti-Claisen condensation (formylation) of esters to give α-formyl esters, (E)- and (Z)-stereocomplementary enol tosylation using TsCl-N-methylimidazole-Et3N and LiOH, and stereoretentive Suzuki-Miyaura cross-coupling.
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H. Nishikado, H. Nakatsuji, K. Ueno, R. Nagase, Y. Tanabe, Synlett, 2010, 2087-2092.
H. Nakatsuji, K. Ueno, T. Misaki, Y. Tanabe, Org. Lett., 2008, 10, 2131-2134.
Key Words
Claisen Condensation, β-Keto Esters, Sulfonates, Suzuki Coupling, Styrenes
ID: J54-Y2009-2800