Exploiting Anion-π Interactions for Efficient and Selective Catalysis with Chiral Molecular Cages

Exploiting anion-pi interactions in catalyst design is a fascinating direction to develop new and fundamental catalysis. For the appealing yet flexible yr-face activation, can two or more pi-acidic surfaces be manipulated for cooperative activation to achieve efficient transformation and particularly selectivity control is highly desirable. Here, we demonstrate a supramolecular pi-catalysis strategy by establishing cooperative pi-face activation in a confined electron-deficient cage cavity. The catalysts have a triazine based prism-like cage core and pendant chiral base sites. Only 2 mol % of cage catalyst efficiently catalyzed the decarboxylate Mannich reactions of sulfamate-headed cyclic aldimines and a series of malonic acid half thioesters in nearly quantitative yields and up to 97 % ee, enabling an unprecedent organocatalytic approach. The supramolecular pi-cavity is essential in harnessing cooperative anion-pi interactions for the efficient activation and excellent selectivity control.