Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex an...Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex and [Bmim]BF4 showed high catalytic activity, diastereoselec-tivity, stability, and reusability in the one-pot synthesis of (E)-α,β-unsaturat-ed ketones through highly selective crossed-condensation of ketones and aldehydes. Through switching the reaction from homogeneous to heterogeneous, the system shows facile separation ability and facile reusability.展开更多
In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabis...In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabismocine framework was examined for the first time for the coupling of CO_(2) into cyclic carbonates,using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions.It is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO_(2) with a wide range of terminal epoxide.The selectivity of propylene carbonates could reach 100%,and the maximum turnover frequency was up to 10740 h^(-1) at 120℃ and 3 MPa CO_(2) pressure when tetrabutylammonium iodide was used as co-catalyst.Moreover,the catalyst is environment friendly,resistant to air and water,and can be readily reused and recycled without any loss of activity,demonstrating a potential in industrial application.展开更多
The crystal of triphenylbismuth bis (Salicylate) pentavalent was synthesized from the reaction of triphenylbismuth dichloride with salicylic acid dissolved in methylene chloride at room temperature. The molecular and ...The crystal of triphenylbismuth bis (Salicylate) pentavalent was synthesized from the reaction of triphenylbismuth dichloride with salicylic acid dissolved in methylene chloride at room temperature. The molecular and crystal structures of triphenylbismuth bis (Salicylate) were determined by X-ray diffraction analysis. This compound crystallizes in the triclinic space group with crystallographic parameters: a = 11.2937 (3) , b = 14.6516 (3) , c = 17.8253 (4) , α = 78.2958 (7)o, β = 76.232 (6)o, γ = 85.351 (6)o, u=6.332mm, V = 2803.59 (11) , Z=2, Dc=1.693g/cm, F(000)=1392, T=293(2)K. The final residual factor is 0.0602 for 5806 reflexions with . The bismuth atom of the compound has a distorted trigonal-bipyramidal configuration.展开更多
In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydro...In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO_(2) cycloaddition onto epoxides.The hypervalent bismuth compounds show good ability for association and dissociation with CO_(2).The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction.The heterogeneous catalysts,viz.Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid,are efficient for the synthesis of cyclic carbonate from CO_(2) and epoxide.It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.展开更多
文摘Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex and [Bmim]BF4 showed high catalytic activity, diastereoselec-tivity, stability, and reusability in the one-pot synthesis of (E)-α,β-unsaturat-ed ketones through highly selective crossed-condensation of ketones and aldehydes. Through switching the reaction from homogeneous to heterogeneous, the system shows facile separation ability and facile reusability.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20507005)Outstanding Young Research Award of National Natural Science Foundation of China(Grant No.E50725825).
文摘In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabismocine framework was examined for the first time for the coupling of CO_(2) into cyclic carbonates,using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions.It is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO_(2) with a wide range of terminal epoxide.The selectivity of propylene carbonates could reach 100%,and the maximum turnover frequency was up to 10740 h^(-1) at 120℃ and 3 MPa CO_(2) pressure when tetrabutylammonium iodide was used as co-catalyst.Moreover,the catalyst is environment friendly,resistant to air and water,and can be readily reused and recycled without any loss of activity,demonstrating a potential in industrial application.
文摘The crystal of triphenylbismuth bis (Salicylate) pentavalent was synthesized from the reaction of triphenylbismuth dichloride with salicylic acid dissolved in methylene chloride at room temperature. The molecular and crystal structures of triphenylbismuth bis (Salicylate) were determined by X-ray diffraction analysis. This compound crystallizes in the triclinic space group with crystallographic parameters: a = 11.2937 (3) , b = 14.6516 (3) , c = 17.8253 (4) , α = 78.2958 (7)o, β = 76.232 (6)o, γ = 85.351 (6)o, u=6.332mm, V = 2803.59 (11) , Z=2, Dc=1.693g/cm, F(000)=1392, T=293(2)K. The final residual factor is 0.0602 for 5806 reflexions with . The bismuth atom of the compound has a distorted trigonal-bipyramidal configuration.
基金The financial supports of the National Natural Science Foundation of China(Grant Nos.20507005 and 20873038)Outstanding Young Research Award of National Natural Science Foundation of China(Grant No.E50725825)Hong Kong Baptist University(FRG/08-09/II-09)。
文摘In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO_(2) cycloaddition onto epoxides.The hypervalent bismuth compounds show good ability for association and dissociation with CO_(2).The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction.The heterogeneous catalysts,viz.Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid,are efficient for the synthesis of cyclic carbonate from CO_(2) and epoxide.It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.
