Lewis Acid-Catalyzed Diastereoselective Domino Reaction of Ene-Ynamide with Trimethylsilyl Cyanide to Construct Spiroindolines

The Zn(OTf)(2)-catalyzed domino reaction of enamide-ynamides in the presence of trimethylsilyl cyanide as an external nucleophile to construct spirocyclic indolines was developed. This domino reaction involved cyclization of enamide to ynamide to generate 4',5'-dihydrospiro[indoline-3,3'-pyrrol]-1'-ium followed by cyanide addition to produce spiroindolopyrrolidines with good diastereoselectivity.

Automated summary

A Zn(OTf)(2)-catalyzed domino reaction was developed for the synthesis of spirocyclic indolines from enamide-ynamides in the presence of trimethylsilyl cyanide. This reaction involved the cyclization of enamide to ynamide followed by cyanide addition, resulting in the formation of spiroindolopyrrolidines with excellent diastereoselectivity.