Transformation of Metal–Organic Framework Secondary Building Units into Hexanuclear Zr-Alkyl Catalysts for Ethylene Polymerization

We report the stepwise and quantitative transformation of the Zr 6 (μ 3 -O) 4 (μ 3 -OH) 4 (HCO 2 ) 6 nodes in Zr-BTC (MOF-808) to the [Zr 6 (μ 3 -O) 4 (μ 3 -OH) 4 Cl 12 ] 6– nodes in ZrCl 2 -BTC, and then to the organometallic [Zr 6 (μ 3 -O) 4 (μ 3 -OLi) 4 R 12 ] 6– nodes in ZrR 2 -BTC (R = CH 2 SiMe 3 or Me). Activation of ZrCl 2 -BTC with MMAO-12 generates ZrMe-BTC, which is an efficient catalyst for ethylene polymerization. ZrMe-BTC displays unusual electronic and steric properties compared to homogeneous Zr catalysts, possesses multimetallic active sites, and produces high-molecular-weight linear polyethylene. Metal–organic framework nodes can thus be directly transformed into novel single-site solid organometallic catalysts without homogeneous analogs for polymerization reactions.