Reported here are the isolation, structural characterization, and decomposition kinetics of the four-coordinate pentachloroethyl nickel complex, NiCl(CCl2CCl3)(CNAr((Mes2))(2) (Ar((Mes2)) = 2,6-(2,4,6-Me3C6H2)(2)C6H3). This complex is a unique example of a kinetically persistent beta-chloroalkyl in a system relevant to coordination-insertion polymerization of polar olefins. Kinetic analysis of NiCl(CCl2CCl3)(CNAr((Mes2))(2) decomposition indicates that beta-chloride (beta-Cl) elimination proceeds by a unimolecular mechanism that does not require initial dissociation of a CNAr((Mes2)) ligand. The results suggest that a direct beta-Cl elimination pathway is available to four-coordinate, Group 10 metal vinyl chloride polymerization systems.