The calcined Mg-A1 layered double hydroxides （LDHs） with a Mg/A1 molar ratio of 3 ： 1 were synthesized and characterized thoroughly by X-ray diffraction （XRD）, temperature-programmed desorption （TPD） of CO2, an...The calcined Mg-A1 layered double hydroxides （LDHs） with a Mg/A1 molar ratio of 3 ： 1 were synthesized and characterized thoroughly by X-ray diffraction （XRD）, temperature-programmed desorption （TPD） of CO2, and thermogravimetric analysis （TGA）. Thus the calcined Mg-A1 LDHs were used as catalyst for the catalytic synthesis of disubstituted ureas from amines and CO2. The effects of reaction time, reaction temperature, pressure, solvent and calcined temperature on activity have been investigated. The results indicated that aliphatic amines, cyclo- hexylamine and benzylamine can be converted to the corresponding ureas selectively over the calcined Mg-A1 LDHs catalysts with N-methyl-2-pyrrolidone （NMP） as solvent without using any dehydrating regent. The catalyst can be recycled several times with only slight loss of activity.展开更多
以2-氯异烟酸为起始原料,在氯化氢催化下和甲醇经酯化反应合成纯度98.5%以上的医药中间体2-氯异烟酸甲酯,收率77.7%。目标化合物进行了1 H NMR、IR和GC-MS表征。条件实验表明:当氯化氢浓度为26%,反应温度为40℃,反应时间为3h时,反应效...以2-氯异烟酸为起始原料,在氯化氢催化下和甲醇经酯化反应合成纯度98.5%以上的医药中间体2-氯异烟酸甲酯,收率77.7%。目标化合物进行了1 H NMR、IR和GC-MS表征。条件实验表明:当氯化氢浓度为26%,反应温度为40℃,反应时间为3h时,反应效果最佳。探讨了2-甲氧基异烟酸甲酯副产物产生的原因,并对副产物产生的机理进行了推测。展开更多
Iron can be found in all mammalian cells and is of critical significance to diverse cellular activities within human bodies.Widespread applications and the underlying chemical and biological fundamental explorations o...Iron can be found in all mammalian cells and is of critical significance to diverse cellular activities within human bodies.Widespread applications and the underlying chemical and biological fundamental explorations of iron-based nanomaterials,especially on the biomedical frontiers,have attracted growing interests most recently in the community.In this review,we focus on the catalytic performance of iron-based nanomaterials(termed as nanocatalysts,abbreviated as NCs)and their nanocatalytic biomedical applications in Fenton nanocatalytic therapeutics,nanocatalytic oxygenation-enabled therapeutics,and nanocatalytic peroxidation-enabled biodetections.Fabrication methodologies of the iron-based NCs are also summarized along with their applications.Representative therapeutic performance against malignant tumors,Alzheimer’s disease(and other pathological abnormalities),and nanocatalyticbased biodetection are discussed.Finally,future development prospects of the iron-based NCs are surveyed,aiming to deliver a brighter future for iron-based NCs in nanocatalytic medicine.展开更多
基金The authors are grateful for the support from the Na-tional Natural Science Foundation of China （No. 21073058）, the Research Fund for the Doctoral Program of Higher Education of China （20100074110014）, and the Fundamental Research Funds for the Central Uni-versities.
文摘The calcined Mg-A1 layered double hydroxides （LDHs） with a Mg/A1 molar ratio of 3 ： 1 were synthesized and characterized thoroughly by X-ray diffraction （XRD）, temperature-programmed desorption （TPD） of CO2, and thermogravimetric analysis （TGA）. Thus the calcined Mg-A1 LDHs were used as catalyst for the catalytic synthesis of disubstituted ureas from amines and CO2. The effects of reaction time, reaction temperature, pressure, solvent and calcined temperature on activity have been investigated. The results indicated that aliphatic amines, cyclo- hexylamine and benzylamine can be converted to the corresponding ureas selectively over the calcined Mg-A1 LDHs catalysts with N-methyl-2-pyrrolidone （NMP） as solvent without using any dehydrating regent. The catalyst can be recycled several times with only slight loss of activity.
文摘以2-氯异烟酸为起始原料,在氯化氢催化下和甲醇经酯化反应合成纯度98.5%以上的医药中间体2-氯异烟酸甲酯,收率77.7%。目标化合物进行了1 H NMR、IR和GC-MS表征。条件实验表明:当氯化氢浓度为26%,反应温度为40℃,反应时间为3h时,反应效果最佳。探讨了2-甲氧基异烟酸甲酯副产物产生的原因,并对副产物产生的机理进行了推测。
基金from the National Natural Science Foundation of China(grant nos.21835007 and 22005327)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(grant no.ZDBS-LY-SLH029),Shanghai Municipal Government S&T Project(grant no.17JC1404701)China Postdoctoral Science Foundation(grant nos.2020M671243 and BX20200345).
文摘Iron can be found in all mammalian cells and is of critical significance to diverse cellular activities within human bodies.Widespread applications and the underlying chemical and biological fundamental explorations of iron-based nanomaterials,especially on the biomedical frontiers,have attracted growing interests most recently in the community.In this review,we focus on the catalytic performance of iron-based nanomaterials(termed as nanocatalysts,abbreviated as NCs)and their nanocatalytic biomedical applications in Fenton nanocatalytic therapeutics,nanocatalytic oxygenation-enabled therapeutics,and nanocatalytic peroxidation-enabled biodetections.Fabrication methodologies of the iron-based NCs are also summarized along with their applications.Representative therapeutic performance against malignant tumors,Alzheimer’s disease(and other pathological abnormalities),and nanocatalyticbased biodetection are discussed.Finally,future development prospects of the iron-based NCs are surveyed,aiming to deliver a brighter future for iron-based NCs in nanocatalytic medicine.
