Co3O4‑Promoted Cerium Oxide Catalyst for Efficient Catalytic N‑Alkylation of Amines with Alcohols
Jianyao Kou1, Guangyao Yang2, Zhixin Yu1
1School of Pharmacy and Institute for Advanced Study, Nanchang University, Nanchang 330031, Jiangxi, P. R. China.
Abstract:
The use of heterogeneous catalysts to generate amine compounds through anaerobic N-alkylation of alcohols via hydrogen transfer strategy is a highly promising synthetic strategy, as it can construct C-N bonds under relatively mild and green conditions. Moreover, amine compounds are widely used in the synthesis of pharmaceutical intermediates, agriculture and fine chemicals. In this work, we successfully constructed a novel Co3O4/CeO2 catalyst using the hydrothermal synthesis method and applied it to the N-alkylation reaction of alcohols, achieving up to 99% of the target product yield with broad substrate scope and high catalyst stability. The Ce3+/Ce4+ redox pairs and oxygen vacancies in the CeO2 support with highly dispersed Co species synergistically catalyze the hydrogen borrowing process of alcohols and amines to generate secondary amines with high activity and selectivity.
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