Synthesis of Functionalized Benzo[g]indoles and 1-Naphthols via Carbon-Carbon Triple Bond Breaking/Rearranging.

Novel carbon-carbon triple bond breaking and rearranging reactions of benzene-linked allene-ynes have been established. The reactions can be selectively controlled toward the formation of two families of skeletally diverse benzo[g]indoles and 1-naphthols under mild conditions. Silver salt was found to efficiently promote indole annulation to give multifunctional benzo[g]indoles with the installation of two sulfonyl groups into the indole ring via N-S and N-F bond cleavage of NFSI, whereas NBS and NCS-mediated benzannulations occurred with the formation of dihalogenated 1-naphthols.