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Alkene oligomerization on heterogeneous Ni-based catalysts has been studied for several decades, with recent attention focused on the preparation, structure and function of Ni active site motifs isolated within microporous and mesoporous supports, including zeolites and metal–organic frameworks (MOFs). This mini-review focuses on the active site requirements and the microscopic kinetic and mechanistic details that become manifested macroscopically as activation and deactivation behavior during oligomerization catalysis and that determine measured reaction rates and selectivity among alkene isomer products. The preponderance of mechanistic evidence is consistent with the coordination–insertion (Cossee–Arlman) cycle for alkene oligomerization prevailing on heterogeneous Ni-exchanged zeolites and MOFs, even when external co-catalysts are not present, as they often are in homogeneous Ni-based oligomerization catalysis. Certain mechanistic features of the coordination–insertion route allow catalyst and active site design strategies to influence product selectivity. Our mini-review provides a critical discussion of reported alkene oligomerization data and the challenges in their measurement and interpretation and concludes with an outlook for future research opportunities to improve our kinetic and mechanistic understanding of alkene chain growth chemistries mediated by Ni-based porous catalysts. 

Abstract Ni cation sites exchanged onto microporous materials catalyze ethene oligomerization to butenes and heavier oligomers but also undergo rapid deactivation. The use of mesoporous supports has been reported previously to alleviate deactivation in regimes of high ethene pressures and low temperatures that cause capillary condensation of ethene within mesoporous voids. Here, we reproduce these prior findings on mesoporous Ni‐MCM‐41 and report that, in sharp contrast, reaction conditions that nominally correspond to ethene capillary condensation in microporous Ni‐Beta or Ni‐FAU zeolites do not mitigate deactivation, likely because confinement within microporous voids restricts the formation of condensed phases of ethene that are effective at solvating and desorbing heavier intermediates that are precursors to deactivation. Deactivation rates are found to transition from a first‐order to a second‐order dependence on Ni site density in Ni‐FAU zeolites with increasing ethene pressure, suggesting a transition in the dominant deactivation mechanism involving a single Ni site to one involving two Ni sites, reminiscent of the effects of increasing H₂pressure on changing the kinetic order of deactivation in our prior work on Ni‐Beta zeolites.