One-pot synthesis of fused pyrroles through a key gold-catalysis-triggered cascade.

A two-step, one-pot synthesis of fused pyrroles is realized by firstly condensing an N-alkynylhydroxammonium salt with a readily enolizable ketone under mild basic conditions and then subjecting the reaction mixture to a gold catalyst, which triggers a cascade reaction involving a facile initial [3.3]-sigmatropic rearrangement of the gold-catalysis product, that is, an N,O-dialkenylhydroxamine. The reaction provides a facile access to polycyclic pyrroles in moderate to good yields.