Nitrile-ligated zinc(II) complexes incorporating aluminum-based weakly coordinating anions (WCAs) have been successfully prepared and fully characterized. An X-ray crystal structure proves both the octahedral symmetry of the zinc(II) cation having six nitrile ligands and the non-coordinating nature of the anion. Similar to complexes bearing boran-based WCAs, the compounds described here can be applied to polymerize isobutylene at room temperature resulting in polyisobutylene with a high content of exo double bonds.