Engineering Corrole and Porphyrin-Based Multivariate Metal-Organic Frameworks for Si-H Bond Insertion

As a contracted porphyrin analogue, corrole shows a more acidic and trinegative/triprotic nature compared with porphyrin in the field of coordination chemistry. However, the direct introduction of corrole into a metal-organic framework is quite difficult due to its lower C symmetry. Herein, we report the one-pot synthesis of a series of corrole and porphyrin-based multivariate porphyrinic metal-organic frameworks M₁(TCPC)@M₂-PCN-222 (M₁ = Cu^III, Mn^III, Fe^IVCl; TCPC = 5,10,15-tris(4-carboxyphenyl) corrole; M₂ = Co^II, Cu^II, Ni^II, Fe^IIICl) and applied them to the insertion of a Si-H bond with α-diazoacetates. The resultant FeCl(TCPC)@Ni-PCN-222 displayed the highest efficiency with a turnover number of 796 based on the amount of Fe, which could be reused at least 5 times without a negligible loss of activity. Mechanistic studies disclosed that the reactivity of FeCl(TCPC)@Ni-PCN-222 came from the synergistic effect between FeCl(TCPC) and Ni-PCN-222, in which FeCl(TCPC) acted as the active site in the formation of metal-carbene, whereas Ni-PCN-222 helped condense the silane molecules for boosting the insertion of the Si-H bond.