Chemoselective Synthesis of Sulfenylated Spiroindolenines from Indolyl-ynones via Organosulfenyl Chloride-Mediated Dearomatizing Spirocyclization

A metal-free sulfenylation/spirocyclization of indolyl-ynones realized by organosulfenyl chloride, generated in situ from the reaction of disulfides and PhICl2, is presented. This cascade one-pot process enables a chemoselective synthesis of diverse sulfenylated spiroindolenines depending on the substituent pattern at the two-position of indolyl-ynones.