β‐Ketodithioesters as Versatile Building Blocks for the Diversity Oriented Synthesis of Thioamides, α‐Allylated‐Thioesters and Ketoamides

Abstract

AbstractWhen β‐ketodithioesters (β‐KDEs) are treated with various electrophiles in multi‐component reactions, three types of highly substituted and densely functionalized reactive intermediates are generated in good yields. Dual role of piperidine as base and nucleophile in Knoevenagel condensation reactions of aromatic aldehydes and β‐ketodithioesters has been observed in our investigations. Trisubstituted (Z)‐prop‐2‐en‐1‐ones have been obtained stereoselectively as a result of these condensation reactions. β‐KDEs were further utilized in allylation reactions with allyl bromide and alkylamines leading to allylated β‐ketodithioestersand allylated β‐ketoamides in good yields.