Selective hydrogenation of carbon–carbon double bond catalyzed by FLP-MOFs

Abstract

Selective hydrogenation of CC double bond in α, β-unsaturated carbonyl compounds is of great significance in the production of fine chemicals, and the design and preparation of hydrogenation catalysts with high selectivity is the key to realize the industrialization of this reaction. Controlling and adjusting the steric hindrance between substrate molecules and active center of catalysts is an effective strategy to achieve high selectivity. In this work, the spatially hindered “Frustrated Lewis pairs” (FLPs) was used as the active component and metal-organic frameworks (MOFs) materials with a certain window size were used as the catalyst support. We designed and synthesized a heterogeneous hydrogenation catalyst B(C6F5)3/DO-MIL-101 by immobilizing FLP onto metal-organic frameworks (MIL-101). Characterizations and catalytic performance tests revealed that the catalytically active species B(C6F5)3/DO was confined in MIL-101 nanocavities via Cr–O coordination bond. The resulting B(C6F5)3/DO-MIL-101 catalyst not only realized the recycling of FLP, but also showed excellent catalytic activity and high selectivity in the selective hydrogenation of CC double bond in α, β-unsaturated carbonyl ketones. It should be noted that the steric hindrance between FLP and substrate molecules, as well as the shape selectivity of MOFs nanocages, are the principal factors for the high selectivity of the catalyst.