Tandem Condensation-Hydrogenation to Produce Alkylated Nitriles Using Bifunctional Catalysts: Platinum Nanoparticles Supported on MOF-Derived Carbon

摘要

Tandem catalysis, which allows multiple steps of a reaction to take place without the need for separation and purification, is highly desired for the design of efficient and environmentally-friendly chemical processes. Herein, the pyrolysis of UiO-66-NH2, an amino-functionalized metal-organic framework, produces nitrogen-rich carbon-ZrO2 composite (CN-ZrO2). This composite is rich in basic sites and effectively catalyzes the Knoevenagel condensation reaction. After loading Pt nanoparticles onto this composite support, a tandem catalyst (Pt/CN-ZrO2) is produced to be capable of the one-step Knoevenagel condensation-hydrogenation reaction to produce an alpha-alkylated nitrile. The tandem catalyst exhibits >99 % aldehyde conversion and >99 % selectivity toward alpha-alkylated nitrile under 1 MPa H-2 at 80 degrees C. This catalyst could be reused for five times in the presence of malononitrile without significant deactivation and is versatile for one-step condensation-hydrogenation of various aldehydes. The good performance of Pt/CN-ZrO2 could be ascribed to the synergistic interaction between Pt and CN-ZrO2 composite supports that lead to the appropriate hydrogenation activity of supported Pt nanoparticles.