N‐ Benzyldithiocarbamate Salts as Sulfur Sources to Access Tricyclic Thioheterocycles Mediated by Copper Species

Using an easily prepared triethylammonium N ‐benzyldithiocarbamate salt as a sulfur source, a dual C−S functionalization of cyclic diaryliodoniums to form tricyclic thioheterocycles is realized. Our method uses the readily available copper sulfate to accelerate the chemical transformation under mild conditions. A broad range of cyclic diaryliodoniums with a ring size from 5‐ to 7‐membered can be employed to gain a quick access to tricyclic thioheterocycles including dibenzothiophenes, thioxanthenes, and phenoxathiines.