Novel axially chiral bis-arylthiourea-based organocatalysts for asymmetric Friedel–Crafts type reactions

It has been shown that catalytic amounts (10–20 mol %) of novel axially chiral bis-arylthioureas promote the asymmetric organocatalytic Friedel–Crafts type addition of indole and N-methylindole to nitroolefins. The optimum catalyst is capable of promoting the reaction between challenging substrates such as N-methylindole and nitroolefins bearing aliphatic β-substituents with enantioselectivity unprecedented for an organocatalytic system.