Ambidoselective Dithiocarboxylation and Thiocarbamoylation of β‐Keto Enolates

Abstract

Abstract Treatment of β‐keto enolates 1 with carbon disulfide in the presence of sodium hydride and subsequent alkylation yield the open‐chain or cyclic acylformylketene S , S ‐acetals 3 and 4 , respectively. Thiophenes 5 , 6 , or 7 and thieno[2,3‐ b ]thiophenes 8 are formed by using as alkylating agents first methyl iodide and then an α‐CH‐acidic halo compound or only two equivalents of the latter. β‐Keto enolates 1 also react with phenyl isothiocyanate to give acylformylketene S,N ‐acetals 10 , aroylthiophenes 11 or thiazolidin‐4‐ones 12 .