Synthesis of Trisubstituted Furans from Epoxypropargyl Esters by Sequential SmI2-Promoted Reduction-Elimination and Pd(II)-Catalyzed Cycloisomerization
José M. Aurrecoechea, Elena Pérez and Mónica Solay
*Hétérochimie Fondamentale et Appliquée (UMR 5069 CNRS), Université Paul-Sabatier, 118 route de Narbonne, 31062 Toulouse Cédex, France
J. M. Aurrecoechea, E. Pérez, M. Solay, J. Org. Chem., 2001, 66, 564-569.
DOI: 10.1021/jo0014257
Abstract
SmI2 promotes a formation of unstable 2,3,4-trien-1-ols from 4,5-epoxyalk-2-ynyl esters via reduction and elimination of an acetate or benzoate leaving group. A subsequent Pd(II)-catalyzed cycloisomerization provides furans in the presence of a proton source. The whole one-pot sequence takes place under mild reaction conditions and tolerates some useful functional groups.
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proposed reaction pathway and catalytic cycle for Pd-catalyzed
cycloisomerization
Key Words
ID: J42-Y2001