Synthesis of Unprotected and Highly Substituted Indoles by the Ruthenium(II)-Catalyzed Reaction of Phenyl Isocyanates with Diaryl/Diheteroaryl Alkynes/Ethyl-3-phenyl Propiolates

A one-pot transformation has been developed for the synthesis of unprotected and highly substituted indoles by an in situ installed carbamide-directed Ru(II)-catalyzed intermolecular oxidative annulation of phenyl isocyanates with diaryl/diheteroaryl alkynes/ethyl phenyl propiolates in the presence of Cu(OAc)(2)center dot H2O as an oxidant and AgSbF6 as an additive at 120 degrees C within 3 h.

Automated summary

A one-pot transformation has been developed for the synthesis of unprotected and highly substituted indoles by an in situ-installed carbamide-directed Ru(II)-catalyzed intermolecular oxidative annulation of phenyl isocyanates with diaryl/diheteroaryl alkynes/ethyl phenyl propiolates in the presence of Cu(OAc)(2)center dot H2O as an oxidant and AgSbF6 as an additive at 120 degrees C within 3 h. The method is efficient with mild reaction conditions and short reaction time.