Selective oxidation of cyclohexene to cyclohexenyl hydroperoxide catalyzed by N-hydroxyphthalimide (NHPI) was studied. Kinetic observations and ¹³C and ¹H NMR spectroscopy showed that accumulation of cyclohexenyl hydroperoxide was accompanied by deactivation of the catalyst. A mechanism of the deactivation through phthalimido N-oxyl radical (PINO) addition to vinyl position of olefin was suggested. Responsible for the deactivation, PINO-C₆H₁₀-OOH hydroperoxide adducts were detected in the reaction conditions, and their molecular structure was elucidated by DFT technique. The mechanism explained an unexpected experimental effect, that is, lowering the oxygen partial pressure improved the stability of NHPI without decrease in production of cyclohexenyl hydroperoxide.

研究了N-羟基邻苯二甲酰亚胺（NHPI）催化的环己烯选择性氧化为环己烯基过氧化氢的反应。动力学观察和¹³ C和¹ H NMR光谱表明，环己烯基过氧化氢的积累伴随着催化剂的失活。提出了通过邻苯二甲酰亚胺基N-氧基（PINO）加成到烯烃的乙烯基而失活的机理。负责停用PINO-C ₆ H ₁₀在反应条件下检测到-OOH氢过氧化物加合物，并通过DFT技术阐明了它们的分子结构。该机理解释了出乎意料的实验效果，即降低氧分压可提高NHPI的稳定性，而不会降低环己烯基过氧化氢的产生。