Bifunctional Noble-Metal-Free Catalyst for the Selective Aerobic Oxidation-Knoevenagel One-Pot Reaction: Encapsulation of Polyoxometalates into an Alkylamine-Modified MIL-101 Framework

One-pot reactions offer economic and environmental advantages. Therefore, the design and synthesis of multifunctional catalysts capable of catalyzing multistep organic transformations are highly important. Herein, an effective bifunctional heterogeneous catalyst is presented. For the first time, the encapsulation of H5PMo10V2O40 (PMoV2) polyoxometalate into the cages of an alkylamine-modified MIL-101 using an optimized double-solvent method is reported. The obtained PMoV2@DETA-MIL-101 material displays a great catalytic performance (99% conversion of alcohols) for the selective aerobic oxidation-Knoevenagel one-pot reaction. To the best of our knowledge, this is one of the first reports on the usage of noble-metal-free catalysts for the aerobic oxidation-Knoevenagel one-pot reaction without the addition of additives. The catalyst is very stable and can be used for at least five cycles with no leaching of the active sites.

Automated summary

The study presents an effective bifunctional heterogeneous catalyst by encapsulating a polyoxometalate into the cages of an alkylamine-modified MIL-101, achieving a great catalytic performance for the selective oxidation-Knoevenagel one-pot reaction with 99% conversion rate.