An electrochemical sulfonylation-triggered
cyclization
reaction
of indole-tethered terminal alkynes with sulfinates as sulfonyl sources
has been developed, which affords exocyclic alkenyl tetrahydrocarbazoles
in good chemical yields. This reaction features convenient operation
and tolerates a wide scope of substrates with a variety of electronically
and sterically diverse substituents. Furthermore, high E-stereoselectivity is observed for this reaction, which provides
an efficient method for the preparation of functionalized tetrahydrocarbazole
derivatives.