We report that a synthetic, vase-shaped host molecule forms complexes with quinuclidine and accelerates the Menschutkin reaction in the nanoenvironment that the host provides. Kinetic simulation is used to determine rate constants for reactions of the complex, and these are compared to control reactions in the absence of the host. The efficacy of the host in effecting this supramolecular acceleration is dependent on the structures of the alkylating agent and its leaving group.