Synthesis of substituted 2-cyclopenten-1-ones from oxodithioesters via a domino process

Article abstract of DOI:10.1016/S0040-4039(99)00238-5

Freshly prepared sulfines of δ-oxodithioesters underwent chemoselective addition of methyllithium to the electron poor sulfur atom of the thiocarbonyl moiety. Subsequent ring closure was effected by intramolecular addition of the carbanion, generated in situ, to the 8-carbonyl function leading to 2-cyclopenten-1-ones. While most described intramolecular procedures involve a base-catalysed cyclisation, our method is induced by an addition reaction. It is a new efficient synthesis of substituted 2- cyclopenten-1-ones via a domino process.