Azobenzene and its derivatives are key raw materials and it is an environmentally friendly method for the preparation of azobenzene by hydrogenative coupling of nitrobenzene. The development of nickel based catalyst f...Azobenzene and its derivatives are key raw materials and it is an environmentally friendly method for the preparation of azobenzene by hydrogenative coupling of nitrobenzene. The development of nickel based catalyst for organic transformations is of importance because of its relatively low cost and toxicity. In this work, we found that ethylenediamine can enrich the electron state of Ni and make the azobenzene easily desorb from the surface of the catalyst, which inhibits the hydrogenation of azobenzene to aniline. The selectivity of azobenzene is greatly improved. When the ratio of Ni and ethylenediamine is 1:10, the yield of the azobenzene can reach 95.5%.展开更多
Selective hydrodeoxygenation of biomass-derived aromatic alcohols to value-added chemical or fuel is of great importance for sustainable biomass upgrading,and hydrodeoxygenation of 5-hydroxymethylfurfural(HMF)to 2,5-d...Selective hydrodeoxygenation of biomass-derived aromatic alcohols to value-added chemical or fuel is of great importance for sustainable biomass upgrading,and hydrodeoxygenation of 5-hydroxymethylfurfural(HMF)to 2,5-dimethylfuran(DMF)is one of the most attractive reactions.Achieving the conversion of HMF to DMF using H_(2)at ambient temperature is challenging.In this work,we used PdCu nanoalloys to catalyze the selective hydrodeoxygenation reaction of HMF to DMF using H_(2)as the reducing agent.The reaction path and the product selectivity are governed by the crystallographic phase of the PdCu nanoalloys.It was discovered that body-centered cubic(BCC)PdCu nanoalloys supported on activated carbon(AC)exhibited outstanding performance with 93.6%yield of DMF at room temperature(PdCu/AC-BCC).A combination of experimental and density functional theory(DFT)studies showed that the tilted adsorption modes of furanic intermediates on PdCu-BCC nanoalloy surfaces accounted for the high selectivity of DMF;however,furan ring was activated on PdCu face-centered cubic(FCC)nanoalloy surfaces.Furthermore,PdCu/AC-BCC could also catalyze the hydrodeoxygenation of other aromatic alcohols at room temperature while maintaining the aromatic structures.This work opens the way for selective hydrodeoxygenation of the aromatic alcohols at room temperature with the aromatic ring intact.展开更多
基金the National Natural Science Foundation of China (No. 21603235)the Recruitment Program of Global Youth Experts of China
文摘Azobenzene and its derivatives are key raw materials and it is an environmentally friendly method for the preparation of azobenzene by hydrogenative coupling of nitrobenzene. The development of nickel based catalyst for organic transformations is of importance because of its relatively low cost and toxicity. In this work, we found that ethylenediamine can enrich the electron state of Ni and make the azobenzene easily desorb from the surface of the catalyst, which inhibits the hydrogenation of azobenzene to aniline. The selectivity of azobenzene is greatly improved. When the ratio of Ni and ethylenediamine is 1:10, the yield of the azobenzene can reach 95.5%.
基金supported by the National Natural Science Foundation of China(21871277,22003069,21725301,21932002)National Key Research and Development Program of China(2017YFB0602200)Beijing Municipal Science&Technology Commission(Z191100007219009).
文摘Selective hydrodeoxygenation of biomass-derived aromatic alcohols to value-added chemical or fuel is of great importance for sustainable biomass upgrading,and hydrodeoxygenation of 5-hydroxymethylfurfural(HMF)to 2,5-dimethylfuran(DMF)is one of the most attractive reactions.Achieving the conversion of HMF to DMF using H_(2)at ambient temperature is challenging.In this work,we used PdCu nanoalloys to catalyze the selective hydrodeoxygenation reaction of HMF to DMF using H_(2)as the reducing agent.The reaction path and the product selectivity are governed by the crystallographic phase of the PdCu nanoalloys.It was discovered that body-centered cubic(BCC)PdCu nanoalloys supported on activated carbon(AC)exhibited outstanding performance with 93.6%yield of DMF at room temperature(PdCu/AC-BCC).A combination of experimental and density functional theory(DFT)studies showed that the tilted adsorption modes of furanic intermediates on PdCu-BCC nanoalloy surfaces accounted for the high selectivity of DMF;however,furan ring was activated on PdCu face-centered cubic(FCC)nanoalloy surfaces.Furthermore,PdCu/AC-BCC could also catalyze the hydrodeoxygenation of other aromatic alcohols at room temperature while maintaining the aromatic structures.This work opens the way for selective hydrodeoxygenation of the aromatic alcohols at room temperature with the aromatic ring intact.
