Ferrocene as a scaffold for effective bifunctional amine–thiourea organocatalysts†
Abstract
A simple and readily accessible prototype of the ferrocene-based bifunctional amine–thioureas shows high enantioselectivity in the Michael addition of acetylacetone to nitroolefins, giving the enantioselectivity of up to 96% ee. This work demonstrates that, in accord with metal catalysis, ferrocene could be an excellent scaffold for chiral organocatalysts.