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.

Substituted 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.