Synthesis of chiral 4-alkyl 4-hydroxy cyclopentenones via a diastereoselective tandem aza-Cope/Mannich cyclization reaction from aldehydosugar
作者:C. Kuhn、G. Le Gouadec、A.L. Skaltsounis、J.-C. Florent
DOI:10.1016/0040-4039(95)00473-p
日期:1995.5
A convenient construction of chiral 4-hydroxy 2-cyclopentenones from alpha-alkoxy aldehyde 6 derived from sugar is reported. A mechanism is proposed involving imine-enamine equilibrium, then alkylation with 2-alkoxypropenyl iodide followed by a tandem 3-aza-Cope/intramolecular Mannich reaction in a one-pot process.
Domino Aza-Claisen/Mannich Cyclization Reaction from a Chiral α-Alkoxy Enamine or Sequential Alkylation of an α-Alkoxy Ester Enolate or Nitrile Anion, Followed by an Intramolecular Wittig Reaction: Two (3+2) Annulation Routes to Homochiral 4-Alkyl-4-hydroxy-2-cyclopentenone Synthesis