MOF-Supported Diimine Nickel Catalyst for Highly Active and Selective Ethylene Dimerization

Selective oligomerization of ethylene remains one of the most significant industrial processes, but it is still dominated by homogeneous catalysis. Herein, we report the synthesis of a heterogeneous α-diimine nickel catalyst (diimine-Ni@PCN-701) through ligand insertion into the Zr-based MOF (PCN-700) framework, affording single-site nickel active sites that are free of steric encumbrances. Diimine-Ni@PCN-701 achieves significant 1-butene selectivity (up to 97.3%) while keeping a considerable turnover frequency (TOF) of 43,800 h–1. This dimerization behavior stems from the electron density of the nickel center induced by the remotely bound Zr (IV) cluster with a carboxylate group on the diimine ligand, as can be analyzed and verified through atomic charge calculation and DFT calculations.