Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ...Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ) oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.展开更多
Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.
bState Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China The differently substituted aromatic nitro compounds were chemoselect...bState Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China The differently substituted aromatic nitro compounds were chemoselectively reduced by Sm/HOAc system in an ionic liquid medium to afford aromatic amines. Under these conditions the other substituents, such as -X, -CHO, -COOH, -CN, -NHTos and -alkyl, remained intact. The notable advantages of this reaction are its mild conditions, simple operation, short reaction time, high yields and easy recycling of ionic liquid.展开更多
Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed ...Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates.This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel.The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH_4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium.Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups.The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.展开更多
The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production,and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of n...The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production,and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of nitroaromatics under mild reaction conditions.In this work,zinc-modified Ni-Ti catalysts(Ni_(x)Zn_(y)Ti_(1))were fabricated and applied for the hydrogenation of nitroaromatics hydrogenation.It was found that the introduction of zinc effectively increases the surface Ni density,enhances the electronic effect,and improves the interaction between Ni and TiO_(2),resulting in smaller Ni particle size,more oxygen vacancies,higher dispersion and greater concentration of Ni on the catalyst surface.Furthermore,the electron-rich Ni^(δ-) obtained by electron transfer from Zn and Ti to Ni effectively adsorbs and dissociates hydrogen.The results reveal that Ni_(x)Zn_(y)Ti_(1)(Ni_(0.5)Zn_(0.5)Ti_(1))shows excellent catalytic performance under mild conditions(70℃and 6 bar).These findings provide a rational strategy for the development of highly active non-noble-metal hydrogenation catalysts.展开更多
文摘Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ) oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.
文摘Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.
基金theNationalNaturalScienceFoundationofChina (No .2 9872 0 10 )theNaturalScienceFoundationofZhejiangProvinceChina (No .2 0 0 72 0 33)
文摘bState Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China The differently substituted aromatic nitro compounds were chemoselectively reduced by Sm/HOAc system in an ionic liquid medium to afford aromatic amines. Under these conditions the other substituents, such as -X, -CHO, -COOH, -CN, -NHTos and -alkyl, remained intact. The notable advantages of this reaction are its mild conditions, simple operation, short reaction time, high yields and easy recycling of ionic liquid.
基金supports for this work by Shahid Chamran University Research Council
文摘Nanoparticles have properties that can be fine-tuned by their size as well as shape.Hence,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates.This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel.The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH_4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium.Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups.The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.
基金supported by the National Natural Science Foundation of China(Grant Nos.22078277,21908185)Project of Hunan Provincial Education Department(Grant Nos.19B572,20B547)the Collaborative Innovation Center of New Chemical Technolo gies Technolo gies for Environmental Benignity and Efficient Resource Utilization,and the National Department of Education Engineering Research Centre for Chemical Process Simulation and Optimization。
文摘The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production,and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of nitroaromatics under mild reaction conditions.In this work,zinc-modified Ni-Ti catalysts(Ni_(x)Zn_(y)Ti_(1))were fabricated and applied for the hydrogenation of nitroaromatics hydrogenation.It was found that the introduction of zinc effectively increases the surface Ni density,enhances the electronic effect,and improves the interaction between Ni and TiO_(2),resulting in smaller Ni particle size,more oxygen vacancies,higher dispersion and greater concentration of Ni on the catalyst surface.Furthermore,the electron-rich Ni^(δ-) obtained by electron transfer from Zn and Ti to Ni effectively adsorbs and dissociates hydrogen.The results reveal that Ni_(x)Zn_(y)Ti_(1)(Ni_(0.5)Zn_(0.5)Ti_(1))shows excellent catalytic performance under mild conditions(70℃and 6 bar).These findings provide a rational strategy for the development of highly active non-noble-metal hydrogenation catalysts.