16. Metal–Organic Framework Nodes Support Single-Site Nickel(II) Hydride Catalysts for the Hydrogenolysis of Aryl Ethers

Yang Song†, Zhe Li†, Pengfei Ji, Michael Kaufmann, Xuanyu Feng, Justin S. Chen, Cheng Wang, and Wenbin Lin* 

Herein we report that the Ti₈-BDC (MIL-125) (BDC is 1,4-benzenecarboxylate) metal–organic framework (MOF) supports single-site solid Ni^II-hydride catalyst for the hydrogenolysis of aryl ethers containing α-O-4, β-O-4, and 4-O-5 linkages to exclusively afford hydrocarbons under mild conditions without the addition of a base. The catalytic activity of Ti₈-BDC-NiH is highly dependent on the reduction of Ti₈(μ₂-O)₈(μ₂-OH)₄ nodes. Density functional theory (DFT) calculations revealed two key steps of σ-bond metathesis in the catalytic cycle of Ti₈-BDC-NiH catalyzed hydrogenolysis. This work highlights the potential of MOF-supported single-site catalysts in aryl ether bond scission and other processes for the efficient production of biofuels and chemical feedstocks.