The Addition of 1-Lithio-1-(phenylthio)alkanes to 2-(N-Methylanilino)acrylonitrile: An Easy Access to 3-(Phenylthio)ketones and 2-Enones

Article abstract of DOI:10.1055/s-1988-27514

A simple and versatile strategy for the synthesis of the title compounds is described.The key-step consists in the addition of 1-lithio-1-(phenylthio)alkanes to 2-(N-methylanilino)acrylonitrile, the nucleophilic phenylthioalkylation of an enol-cation equivalent.Alkylation of the adducts and hydrolysis give 3-(phenylthio)ketones, which can be isolated, or without further purification can be transformed into 2-enones via the well known oxidation-elimination procedure.These reactions are possible with allylic derivatives too, therefore the homologous vinylic compoundscan be prepared by the same way.Pyrolysis of the 1-lithioaminonitriles formed within the first step gives aminonitriles of cyclopropanones via cyclization.