Transition-Metal-Free Synthesis of <i>N-</i>Arylphenothiazines through an <i>N</i>- and <i>S</i>-Arylation Sequence
作者:Tsubasa Matsuzawa、Takamitsu Hosoya、Suguru Yoshida
DOI:10.1021/acs.orglett.1c00515
日期:2021.3.19
transition-metal-free conditions is disclosed. An N- and S-arylation sequence of o-sulfanylanilines enabled us to synthesize a wide variety of N-arylphenothiazines. In particular, one-pot synthesis of N-arylphenothiazines was accomplished from easily available modules through preparation of o-sulfanylanilines by thioamination of aryne intermediates and following N- and S-arylation sequence.
The synthesis of ortho-(trimethylsilyl)triphenylenyl triflates 7 is described. Fluoride-induced decomposition of these triflates leads to the generation of didehydrotriphenylenes (triphenylynes) 6. These arynes undergo [4+2] cycloadditions with dienes to afford the corresponding Diels-Alder adducts or palladium-catalyzed formal [2+2+2] cycloadditions to afford extendedtriphenylenes.