Gold-Catalyzed Synthesis of 2-Sulfenylspiroindolenines via Spirocyclizations

Abstract

2-Phenylsulfenyl-N-propargyl tryptamines have been prepared by electrophilic sulfuration of the corresponding tryptamines. These compounds undergo gold-catalyzed spirocyclizations to the corresponding 2-phenylthiospiroindolenines in good yields. The compounds were analyzed by NMR experiments, infrared, mass spectra and X-ray diffraction. This method provides a new efficient entry to the synthesis of 2-sulfenyl spiroindolic compounds.

Keywords

• gold catalysis
• indoles
• alkynes
• spiro compounds
• sulfenyl group