Annulations of α-carbamoyl ketene dithioacetals with dicarboxylic acid dichlorides: Synthesis of functionalized pyrrolidinetriones and piperidinetriones
An annulation strategy based on ketene dithioacetals is described. Under very mild conditions, a number of pyrrolidinetriones 2 and piperidinetriones 3 have been synthesized by the cycloaddition reaction of α-carbamoyl ketene di-thioacetals 1 with di-carboxylic acid dichlorides in good to excellent yields. Further application of this protocol is highlighted by the synthesis of a set of fused pyrimidine derivatives 4/5 from 2/3 and amidines.
Annulations of α-Carbamoyl Ketene Dithioacetals with Dicarboxylic Acid Dichlorides: Synthesis of Functionalized Pyrrolidinetriones and Piperidinetriones
An annulation strategy based on ketene dithioacetals is described. Under very mild conditions, a number of pyrrolidinetriones 2 and piperidinetriones 3 have been synthesized by the cycloaddition reaction of α-carbamoyl ketene dithioacetals 1 with di-carboxylic acid dichlorides in good to excellent yields. Further application of this protocol is highlighted by the synthesis of a set of fused pyrimidine derivatives 4/5 from 2/3 and amidines.