1344675-04-2Relevant articles and documents
Asymmetric catalysis on the nanoscale: The organocatalytic approach to helicenes
Koetzner, Lisa,Webber, Matthew J.,Martinez, Alberto,Defusco, Claudia,List, Benjamin
, p. 5202 - 5205 (2014)
The first asymmetric organocatalytic synthesis of helicenes is reported. A novel SPINOL-derived phosphoric acid, bearing extended π-substituents, catalyzes the asymmetric synthesis of helicenes through an enantioselective Fischer indole reaction. A variety of azahelicenes and diazahelicenes could be obtained with good to excellent yields and enantioselectivities. Twisting indoles: A novel chiral Bronsted acid, specifically designed for long-range control on a nanoscale, catalyzes the asymmetric synthesis of azahelicenes through a Fischer indolization. The method has the advantage of starting from simple achiral starting materials, which can be modified by changing the protecting group (R2) or the terminal substituents (R1, R3). The products can be further oxidized to polyaromatic systems.