The cascade synthesis of imines from alcohols and nitroarenes via catalytic transfer hydrogenation(CTH)is a highly sustainable process.However,developing efficient non-noble metal catalysts remains a formidable challe...The cascade synthesis of imines from alcohols and nitroarenes via catalytic transfer hydrogenation(CTH)is a highly sustainable process.However,developing efficient non-noble metal catalysts remains a formidable challenge due to the kinetic mismatch of sequential reaction steps and sluggish active hydrogen transfer.Herein,we propose a novel spatial functional partitioning catalyst design paradigm and construct a highly efficient diatomic catalyst featuring atomically dispersed ZnN4 and NiN4 sites spatially bridged by nitrogen atoms.Experimental and theoretical investigations reveal a precise dual-site cooperative mechanism of the unique Zn-N-Ni constructure.Specifically,the highly electron-deficient Zn sites(+1.14|e|vs.+0.83|e|of Ni)preferentially activate the hydroxyl group of benzyl alcohol to generate active H* due to a lower dehydrogenation energy barrier(89.6 kJ mol-1 vs.111.6 kJ mol-1 for Ni).Concurrently,the Ni sites,featuring a higher d-band center(–1.47 eV vs.–5.50 eV for Zn),facilitate nitrobenzene hydrogenation with a significantly lower barrier(73.7 kJ mol-1),while the bridging N serves as an H* adsorption site.Consequently,this synergistic configuration integrates single-atom efficiency with dual-site cooperation,achieving 96%nitrobenzene conversion and 90%imine selectivity.This work not only elucidates the atomic-level hydrogen transfer mechanism in cascade reactions but also establishes a rational design principle for complex tandem catalytic systems.展开更多
Hydroxylamine(NH2OH)is an essential platform molecule,serving as the pivotal precursor for nylon-6 production,with a global annual demand exceeding 106 tons[1-3].Beyond polymer synthesis,NH2OH is also widely applied i...Hydroxylamine(NH2OH)is an essential platform molecule,serving as the pivotal precursor for nylon-6 production,with a global annual demand exceeding 106 tons[1-3].Beyond polymer synthesis,NH2OH is also widely applied in the pharmaceutical,agrochemical and textile industries,underscoring its broad industrial significant.展开更多
基金financially supported by the National Natural Science Foundation of China(22302217 and 52470193)the Shandong Provincial Natural Science Foundation(ZR2023QB049)the Plan for Youth Innovation Team of Colleges in Shandong Province。
摘要The cascade synthesis of imines from alcohols and nitroarenes via catalytic transfer hydrogenation(CTH)is a highly sustainable process.However,developing efficient non-noble metal catalysts remains a formidable challenge due to the kinetic mismatch of sequential reaction steps and sluggish active hydrogen transfer.Herein,we propose a novel spatial functional partitioning catalyst design paradigm and construct a highly efficient diatomic catalyst featuring atomically dispersed ZnN4 and NiN4 sites spatially bridged by nitrogen atoms.Experimental and theoretical investigations reveal a precise dual-site cooperative mechanism of the unique Zn-N-Ni constructure.Specifically,the highly electron-deficient Zn sites(+1.14|e|vs.+0.83|e|of Ni)preferentially activate the hydroxyl group of benzyl alcohol to generate active H* due to a lower dehydrogenation energy barrier(89.6 kJ mol-1 vs.111.6 kJ mol-1 for Ni).Concurrently,the Ni sites,featuring a higher d-band center(–1.47 eV vs.–5.50 eV for Zn),facilitate nitrobenzene hydrogenation with a significantly lower barrier(73.7 kJ mol-1),while the bridging N serves as an H* adsorption site.Consequently,this synergistic configuration integrates single-atom efficiency with dual-site cooperation,achieving 96%nitrobenzene conversion and 90%imine selectivity.This work not only elucidates the atomic-level hydrogen transfer mechanism in cascade reactions but also establishes a rational design principle for complex tandem catalytic systems.
基金supported by the National Natural Science Foundation of China(22408325)the Baima Lake Laboratory Joint Fund of Zhejiang Provincial Natural Science Foundation(LBMHZ25B030007)the Research Funds of Institute of Zhejiang University-Quzhou(IZQ2021RCZX022).
摘要Hydroxylamine(NH2OH)is an essential platform molecule,serving as the pivotal precursor for nylon-6 production,with a global annual demand exceeding 106 tons[1-3].Beyond polymer synthesis,NH2OH is also widely applied in the pharmaceutical,agrochemical and textile industries,underscoring its broad industrial significant.