Michael Reactions in Aprotic Media. An Effective Method of Construction of α,α,β-Trisubstituted Ketones and Application to Natural Product Synthesis

Article abstract of DOI:10.1021/jo00139a016

By proper selection of the reaction conditions, 1,4-additions of malonate and propionate anions to 2-(phenylthio)-2-cyclopentenone were accomplished.Subsequent trapping of the intermediate enolates with an electrophile in the aprotic media afforded α,α,β-trisubstituted ketones regiospecifically.The effects of the counterion, solvent, and temperature were examined.An application of this method to the formal synthesis of the pseudoguaianolides (+/-)-aromatin and (+/-)-confertin is described.