Self‐Assembled Molecular Reaction Vessels Reloaded

Enzyme-like catalysis of Nazarov cyclizations has been achieved by encapsulation of pentadienols into a metallosupramolecular capsule. Constrictive binding of the substrate and functional-group activation give rise to a tremendous rate acceleration of up to a factor of 2.1×106, thus, pushing the efficiency of self-assembled molecular capsules as catalysts to a new level.