Syntheses of Substituted Furans and Pyrroles by Platinum-Catalyzed Cyclizations of Propargylic Oxiranes and Aziridines in Aqueous Media

The reactions of propargylic oxiranes and aziridines with a platinum catalyst in aqueous media are described. Furans having a variety of substituents were conveniently synthesized by the platinum-catalyzed reaction of propargylic oxiranes. The reaction in the presence of N-iodosuccinimide afforded the 3-iodo-substituted furan, which was further functionalized to tetrasubstituted furans with high efficiency. Propargylic aziridines were also reacted with the platinum catalyst to produce the corresponding substituted pyrroles in good yields.