Morphology‐Tuned Activity of Ru/Nb₂O₅ Catalysts for Ketone Reductive Amination

Abstract

Amines are important compounds in natural products and medicines. Specifically, cyclopentylamine is one of the value‐added chemicals widely used in the production of pesticides, cosmetics and medicines. In this work, three Ru/Nb2O5 catalysts with different Nb2O5 morphologies were used in the reductive amination of cyclopentanone under mild reaction conditions (90 °C, 2 MPa H2), among which 1 %Ru/Nb2O5−L catalyst exhibits best performance with the yield of cyclopentylamine reaching 84 %. This catalytic system is stable and has not significant deactivation even after 5 runs in the durability test. In addition, this catalyst can be extended to a series of aldehydes/ketones. Further comprehensive characterizations (XPS analysis and CO‐adsorption DRIFT) reveal that the electronic effect of Ru species can be ruled out; instead, the activity of the catalyst is strongly influenced by the geometric effect. Layered Nb2O5 material possesses the highest surface area, resulting in the highest Ru dispersion, and therefore shows the highest catalytic activity. The in‐situ DRIFT‐MS technique was also used to reveal and understand the reaction mechanism. It is found that Ru species play a key role in activating carbonyl groups. This study illustrates a promising application of Ru/Nb2O5‐Layer catalyst in the synthesis of amine and provides an understanding to the reaction mechanism.

Sustainable access to renewable N-containing chemicals from reductive amination of biomass-derived platform compounds

“…The strategy of reductive amination towards synthesis of nitrogen-containing compounds was also applicable to cyclopentanone as reported by Wang et al [173]. Among the nitrogen-containing derivatives of cyclopentanone, cyclopentylamine is an attractive starting material for the synthesis of medicines, cosmetics, and pesticides, and its synthesis has therefore been scrutinized [173][174][175]. Wang et al highest Ru dispersion, which in turn made a significant effect on improving its catalytic performance [173].…”

“…Cyclopentanone generated from the aqueous-phase hydrogenative ring-rearrangement reaction of furfural is a key building block for the production of medicine, rubber, perfume and high-density fuels [171,172]. The strategy of reductive amination towards synthesis of nitrogen-containing compounds was also applicable to cyclopentanone as reported by Wang et al [173]. Among the nitrogen-containing derivatives of cyclopentanone, cyclopentylamine is an attractive starting material for the synthesis of medicines, cosmetics, and pesticides, and its synthesis has therefore been scrutinized [173][174][175].…”

“…Among the nitrogen-containing derivatives of cyclopentanone, cyclopentylamine is an attractive starting material for the synthesis of medicines, cosmetics, and pesticides, and its synthesis has therefore been scrutinized [173][174][175]. Wang et al highest Ru dispersion, which in turn made a significant effect on improving its catalytic performance [173]. In addition to cyclopentylamine and imine intermediate, some by-products detected in the reaction mixture stemmed from hydrogenation or aldol condensation of cyclopentanone as well as condensation of cyclopentanone with cyclopentylamine, as illustrated in Scheme 20.…”

“…In addition to cyclopentylamine and imine intermediate, some by-products detected in the reaction mixture stemmed from hydrogenation or aldol condensation of cyclopentanone as well as condensation of cyclopentanone with cyclopentylamine, as illustrated in Scheme 20. Moreover, the applied catalytic system was extended to various aldehydes/ketones capable of offering good yields (60-90%) towards the corresponding target products [173]. bioactive compounds and natural products to yield target primary amines [174].…”

Meet the Women of Catalysis

“…Her research interests include nano‐/mesoporous materials and their applications in catalysis, mainly focused on the design of solid acid/base and bifunctional/multifunctional catalysts used in biomass conversion, especially niobium‐based catalysts. An important application is the design of more efficient and durable catalysts for biofuel production from biomass‐derived compounds, with the collaboration of SinoPec …”