Access to substituted thiapyrrolizidinones and fused pyridones using the domino N-acyliminium-thionium equilibrium/1,3-dipolar cycloaddition/desulfurization cyclization cascade

Substituted thiapyrrolizidinones and fused pyridones, and quinolizinones were reported efficaciously from suitable thioamides in yields ranging from 30% to 65%. The reaction proceeded in a one-pot procedure as cascade process by the intramolecular 1,3-dipolar cycloaddition of thioisomünchnones followed by desulfurization of the adducts. During these investigations, the mechanistic aspects of the process were also discussed.

Graphical abstractDownload full-size imageSubstituted thiapyrrolizidinones and fused pyridones, and quinolizinones were synthesized efficiently by thioisomünchnone/1,3-dipolar cycloaddition/desulfurization cyclization cascade in a one-pot procedure from thioamides.