Helically Chiral 1‑Sulfur-Functionalized [6]Helicene: Synthesis, Optical Resolution, and Functionalization

The synthesis and optical resolution of helically chiral 5,6,9,10-tetrahydro-1-[6]­helicenethiol and its subsequent transformations to enantiopure 1-sulfur-functionalized [6]­helicenes are reported. A novel enantiopure [7]­thiahelicene having a thiophene ring at the terminal position of the [6]­helicene skeleton was synthesized

Efficient Enantioselective Synthesis of Oxahelicenes Using Redox/Acid Cooperative Catalysts

An efficient and enantioselective synthesis of oxa[9]­helicenes has been established via vanadium­(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols. A newly developed vanadium complex cooperatively functions as both a redox and Lewis acid catalyst to promote the present sequential reaction and afford oxa[9]­helicenes in good yields with up to 94% ee

Efficient Enantioselective Synthesis of Oxahelicenes Using Redox/Acid Cooperative Catalysts

An efficient and enantioselective synthesis of oxa[9]­helicenes has been established via vanadium­(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols. A newly developed vanadium complex cooperatively functions as both a redox and Lewis acid catalyst to promote the present sequential reaction and afford oxa[9]­helicenes in good yields with up to 94% ee