Establishment of Integrated Analysis Method for Probing and Reconstructing Hydrogenation Mechanism of a Model Reaction

The hydrogenation of 4-nitrophenol (4-NP) has attracted much attention, since it is typically used as a model reaction for evaluating newly developed catalysts, but its mechanism still debated. Herein, Co(OH)2-modified CuO catalyst (Co(OH)2/CuO) was the reduction 4-NP to 4-aminophenol (4-AP) in an aqueous sodium borohydride (NaBH4) solution. investigated by UV-Vis spectroscopy (UV-Vis), high-performance liquid chromatography (HPLC), HPLC-Q-orbitrap high-resolution mass spectrometry (LC-MS/MS), and 1HNMR (1HNMR) integrated technology at different concentrations NaBH4. Samples were taken specified time intervals monitored using UV-Vis, HPLC, LC-MS/MS, 1HNMR. With help comprehensive analysis, eight intermediates, including azo azoxy compounds, effectively captured, variation tendency each intermediate determined, revealing that proceeds via coexistence direct condensation routes. analysis methods powerful technical supports study catalysis mechanism.