One‐Pot Synthesis of Polysubstituted Pyrroles via Sequential Ketenimine Formation/Ag(I)‐Catalyzed Alkyne Cycloisomerisation Starting from Ylide Adducts.

Main observation and conclusion: A simple one pot synthesis of polysubstituted pyrroles via ketenimine formation/Ag(I)‐catalyzed alkyne cycloisomerisation has been developed. The easily accessible phosphorane ylide derivatives reacted with isocyanates, producing highly active ketenimines that were then treated with amines, which afforded substituted pyrroles by a 5‐exo‐dig cyclization/isomerization in the presence of a Ag(I) catalyst in good overall yields. [ABSTRACT FROM AUTHOR]