Silica-supported molybdenum oxide (MoOx/SiO2) with 4.8 wt% Mo (0.5 mmol g−1) was an effective and reusable heterogeneous catalyst for dehydration of 2-furamide to 2-furonitrile (96 % yield). The catalyst was applicable to the dehydration of various amides including heteroaromatic, aromatic and alkyl amides, providing the corresponding nitriles in high yields (87-97 %). Based on the results of catalyst characterizations (XRD, TEM, UV-vis, Raman) and activity tests, MoOx species are highly dispersed over SiO2, and heptamolybdate anion ([Mo7O24]6−) and isolated dioxo ((O=)2MoO2) were mainly formed on the SiO2 support of the optimal MoOx/SiO2 catalyst. The strong Brønsted acid sites (Mo-OH−Si site) can be formed from the MoOx species and the adjacent silanol group, and the acid-base pair site (Mo(=O)−OH−Si site) of the strong Brønsted acid site (Mo−OH−Si site) and base site (Mo=O) over MoOx/SiO2 catalyst could be the main active site for the dehydration of amides.
|出版ステータス||Published - 2022 5月 6|
ASJC Scopus subject areas