Creation through Immobilization: A New Family of High Performance Heterogeneous Bifunctional Iminophosphorane (BIMP) Superbase Organocatalysts

An immobilized chiral bifunctional iminophosphorane superbase organocatalyst has been developed and applied in a range of challenging enantioselective reactions. A unique feature of this novel catalytic system is that the final step creation of the iminophosphorane occurs at the point of immobilization. The utility of the immobilized catalyst system was demonstrated in the nitro-Mannich reaction of ketimines as well as the conjugate addition of high pK a 1,3-dicarbonyl pro-nucleophiles to nitrostyrene. Catalyst recycling was also demonstrated.