温和条件环己烷氧化及原位过氧化物媒介活化作用研究

The activation and selective conversion of hydrocarbon with inert C-H bond under mild condition is a main challenge among the catalytic scientific community. With cyclohexanone production by cyclohexane selective oxidation as the research object, this project was designed to establish the catalytic system realizing the selective oxidation of hydrocarbon containing inert C-H bond such as cyclohexane under mild conditions, mediated by hydrocarbon containing active C-H bond. In this catalytic system, the hydrocarbon containing active C-H bond was oxidized by O2 under mild conditions, forming low concentration of peroxide. With this process as the catalytic oxidation-reduction cycle, the activation and selective oxidation of the inert C-H bond in cyclohexane was realized. The catalyst with core-shell structure will be designed and synthesized. The poor oxidation ability problem of peroxide under low concentration was solved by the “cage effect” of core-shell structure through local enrichment of the peroxide. Finally, the cyclohexane was converted to cyclohexanone efficiently. In order to support this catalytic system, the catalytic cycle and coupling rule of the intermediaries and C-H bond will be researched and illuminated utilizing the method of capturing intermediates, in-situ detection, isotope labeling, etc.

温和条件下利用分子氧实现含惰性C-H键烃类分子的活化和选择转化，是催化科学界的挑战性课题之一。本项目以环己烷选择氧化制环己酮为研究对象，以含活泼C-H键烃类分子为催化媒介，建立环己烷等含惰性C-H键烃类分子温和条件选择氧化的催化体系。所设计的含活泼C-H键的烃类催化体系，在温和条件下容易被分子氧活化，并原位生成低浓度的有机过氧化物；以此为催化氧化-还原循环媒介，实现环己烷分子中惰性C-H键的活化和选择氧化。设计制备核壳结构的催化剂，利用核壳结构的“笼效应”，实现过氧化物的局部富集，解决低浓度过氧化物氧化能力差的问题，实现温和条件下环己烷高效的转化为环己酮。利用中间体捕获、原位检测、同位素标记等手段，阐明中间媒介和C-H键催化循环过程和耦合规律，为该催化体系的研究提供理论支持。

温和条件下利用分子氧实现含惰性C-H键烃类分子的活化和选择转化，是催化科学界的挑战性课题之一。本项目以环己烷选择氧化制环己酮为研究对象，以含活泼C-H键烃类分子为催化媒介，建立了氧气原位活化利用的催化体系，实现了温和条件下底物的选择氧化的催化体系。所设计的含活泼C-H键的烃类催化体系，在温和条件下容易被分子氧活化，并原位生成低浓度的有机过氧化物；以此为催化氧化-还原循环媒介，实现了底物的选择氧化。设计并制备核壳结构的催化剂，利用核壳结构的“笼效应”，实现过氧化物的局部富集，解决低浓度过氧化物氧化能力差的问题，实现氧气的高效利用。利用中间体捕获、原位检测、同位素标记等手段，阐明氧气活化过程与过氧化物利用的耦合规律，为该催化体系的研究提供理论支持。