专业从事离子液体的合成、应用及其相关技术的研究工作----Lanzhou Greenchem ILs/青岛奥立科

• Green and Practical Synthesis of Carbamates from Ureas and Organic Carbonates
• 更新时间：2014-04-10；信息类型：SCI论文
• A practical method for the synthesis of carbamates from ureas and organic carbonates was developed with 100% atom economy using La2O3/SiO2 as catalyst without any additional solvent. The scope of the protocol is demonstrated in the synthesis of 14 carbamates with various functional groups in excellent yields (76–95%).
• 链接地址：http://www.ionike.com/download/article/2014-04-10/134.html

• N-substituted carbamates syntheses with alkyl carbamates as carbonyl source over Ni-promoted Fe3O4 catalyst
• 更新时间：2014-04-10；信息类型：SCI论文
• A series of catalysts of magnetic iron oxide containing Ni with different nickel content were prepared with co-precipitation method and tested in the syntheses of N-substituted carbamates from various amines and alkyl carbamates. Under the optimized reaction conditions, various N-substituted carbamates were successfully synthesized with 90–98% isolated yield. The catalyst could be recovered based on the magnetic property of the catalyst and reused for five runs without deactivation. The catalysts were characterized with X-ray photoelectron spectroscopy, X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption, and Mössbauer spectroscopy analyses. The results showed that the catalytic activity may be derived from the delicate synergy between Ni and Fe species resulted in specific basic sites. Quasi in situ FT-IR and isotopic tracer revealed that the formation of substituted urea was the key step and the N-substituted carbamate was formed via further alcoholysis of the substituted urea.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/131.html

• Atom-economy Synthesis of N-substituted Carbamate from Urea Derivative and Dimethyl Carbonate Catalyzed by La/SiO2: Characterization and Activity
• 更新时间：2014-04-10；信息类型：SCI论文
• A series of silica gel immobilized lanthanum catalysts were prepared for the atom-economy synthesis of N-substituted carbamates from urea derivatives and dimethyl carbonate. The La/SiO2 catalysts with lanthanum loadings varied from 1.3 wt% to 8.5 wt% were characterized by AES, BET, XRD, TEM, FT-IR, XPS and TPD. According to the characterization, lanthanum species with particle sizes of 5—10 nm on the surface of silica gel were formed. The catalysts were all amorphous and the surface areas were 336.5—530.2 m2/g. NH3-TPD analysis showed that all samples exhibited similar acid strength with different acid amounts. FT-IR measurement indicated that the component of lanthanum speci es on the catalyst surface were La(OH)3, LaOOH and hydrated La2O3. Also, the peak value of the absolute amount of LaOOH was obt ained with 4.3 wt% lanthanum loading. The BET surface area decreased dramatically when the lanthanum loading was above 4.3 wt%. In consideration of the results ob-tained from the catalytic reactions, it could be concluded that LaOOH was the possible active species and high sur-face area was important for the high catalytic activity.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/130.html

• MCM-41 Grafted Quaternary Ammonium Salts as Recyclable Catalysts for the Sequential Synthesis of Dimethyl Carbonate from Epoxides, CO2, and Methanol
• 更新时间：2014-04-10；信息类型：SCI论文
• One kind of novel heterogenous bifunctional catalyst, MCM-41 grafted quaternary ammonium salts with terminal amino group, was prepared. These catalysts exhibited excellent catalytic performance and good reusability in the sequential synthesis of dimethyl carbonate from epoxides, CO2, and methanol.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/129.html

• Synthesis of dialkyl hexamethylene-1,6-dicarbamate from 1,6-hexamethylenediamine and alkyl carbamate over FeCl3 as catalyst
• 更新时间：2014-04-10；信息类型：SCI论文
• A series of catalysts (e.g. FeCl3, Zn(OAc)2, Pb(NO3)2, etc.) were tested for the trans-esterification reaction of 1,6-hexamethylenediamine (HDA) with methyl carbamate (MC), ethyl carbamate (EC), and butyl car-bamate (BC) to afford dialkyl hexamethylene-1,6-dicarbamate (AHDC). By applying the optimized condi-tion, 100% conversion of HDA and 93% yield to diethyl hexamethylene-1,6-dicarbamate (EHDC) could be obtained using FeCl3 as catalyst. The desired products could be precipitated by adding water into the resulting mixture, and the activity of recovered catalyst could be maintained.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/118.html

• Copper-Catalyzed Alkylation of Sulfonamides with Alcohols
• 更新时间：2014-04-10；信息类型：SCI论文
• Shi F,Man Kin Tes,Cui XJ,et al. Copper-catalyzed Alkylation Of Sulfonamides With Alcohols[J]. Angew. Chem. Int. Ed.,2009,48:5912-5915.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/115.html

• Copper-Catalyzed N-Alkylation of Sulfonamides with Benzylic Alcohols: Catalysis and Mechanistic Studies
• 更新时间：2014-04-10；信息类型：SCI论文
• The N-alkylation of sulfonamides with alcohols is efficiently performed in the presence of easily available copper catalysts via hydrogen borrowing methodology. Applying a copper acetate/potassium carbonate system the reaction of sulfon-ACHTUNGTRENUNGamides and alcohols gave the corresponding secondary amines in excellent yield. In situ HR-MS analysis indicated that bissulfonylated amines are formed under air atmosphere, which act as self-stabilizing ligands for the catalytic system. UV-visible measurements suggest the interaction between the copper centre and the bissulfonylated amine. Reactions of benzyl alcohol-d7 with p-toluenesulfonamide, Nbenzyl-p-toluenesulfonamide or N-benzylidenetolu-ACHTUNGTRENUNGenesulfonamide revealed that the reaction proceeds via a transfer hydrogenation mechanism and the whole process is micro-reversible. Competitive reactions of benzyl alcohol and benzyl alcohol-d7 with ptoluenesulfonamide revealed a kinetic isotope effect (kH/kD) of 3.287 (0.192) for the dehydrogenation of benzyl alcohol and 0.611 (0.033) for the hydrogenation of the N-benzylidene-p-toluACHTUNGTRENUNGenesulfonamide intermediate, which suggests that dehydrogenation of the alcohol is the rate-determining step.
• 链接地址：http://www.ionike.com/download/article/2014-04-10/114.html

• Synthesis of dialkyl hexamethylenedicarbamate from 1,6-hexamethylenediamine and alkyl carbamate over Y(NO3)3·6H2O catalyst
• 更新时间：2014-04-09；信息类型：SCI论文
• The non-phosgene carbonylation of 1,6-hexamethylenediamine (HDA) with alkyl carbamates using Y(NO3)3·6H2O as a catalyst and the influence of reaction variables on the yields of dialkyl hexamethylenedicarbamate (HDC) were studied. At 453K and in the presence of 5 wt.% Y(NO3)3·6H2O, nearly 100% HDA conversion and 85% dibutyl hexamethylenedicarbamate (BHDC) isolated yield could be achieved when butyl carbamate (BC) was employed as a carbonyl source. During reaction, an induction periodwas observed, but it almost disappeared by pretreating the catalyst with n-butanol. The FT-IR, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations of the catalyst showed that some transformation occurred when the catalyst was pretreated with n-butanol or employed during reaction, i.e., part decomposition of Y(NO3)3 to Y2O3, conversion from crystal to amorphous state, changes occurring in chemical state of the active species, as well as some subtle interactions between the catalyst and n-butanol. All these observed changes might be the reason resulting in activation of the catalyst.
• 链接地址：http://www.ionike.com/download/article/2014-04-09/106.html

• Microwave assisted synthesis and biological activities of 9-boronobenzyladenine derivatives
• 更新时间：2014-04-09；信息类型：SCI论文
• Microwave enhanced syntheses of 9-boronobenzyladenine derivatives by the reaction of adenine with the corresponding bromomethylphenylboric acid were reported. Microwave irradiation reduced the overnight reaction time of conventional thermal methods to 10 min, provided the desired products and increased the yields up to three times. Preliminary in vitro pharmacological tests were also described.
• 链接地址：http://www.ionike.com/download/article/2014-04-09/105.html

• Synthesis of carbamates from aliphatic amines and dimethyl carbonate catalyzed by acid functional ionic liquids
• 更新时间：2014-04-09；信息类型：SCI论文
• Selective synthesis of carbamates from amines and dimethyl carbonate were studied in the presence of various ionic liquids as catalysts. The –SO3H-functionalized ionic liquid was found to be the most active catalyst among the applied ionic liquids, and nearly 100% conversion and 95% selectivity were achieved when using 1,6-hexanediamine as reactant. The acid functional ionic liquid catalyst system is also readily separable and reusable after reaction.
• 链接地址：http://www.ionike.com/download/article/2014-04-09/102.html