Chelate tetra(acetylacetonato) tin(Ⅳ) was prepared and used as catalyst for polytrimethylene terephthalate synthesis.It exhibited higher catalytic activity than tetrabutyl titanate,butyltinhydroxide oxide and dibutyl...Chelate tetra(acetylacetonato) tin(Ⅳ) was prepared and used as catalyst for polytrimethylene terephthalate synthesis.It exhibited higher catalytic activity than tetrabutyl titanate,butyltinhydroxide oxide and dibutyltin oxide.Decrease in reaction time, content of terminal carboxyl group,color intensity and increase in intrinsic viscosity were observed.The unique molecular structure can be considered as factor remarkably improving the catalytic activity of tetra(acetylacetonato) tin(Ⅳ).展开更多
This paper reports mainly the preparation of silica supported acetylacetone ligands and their cobalt complexes, the characterization of their chemical structure, and the evaluation of their catalytic activity in the r...This paper reports mainly the preparation of silica supported acetylacetone ligands and their cobalt complexes, the characterization of their chemical structure, and the evaluation of their catalytic activity in the reaction for the preparation of ethers directly from alkanols and benzyl chloride. The results indicate that those silica supported β-diketone cobalt complexes (SACO) not only can simplify the reaction procedure of the ether preparation but also show a much higher catalytic activity in comparison with other homogeneous catalysts. In addition, SACO can be recovered and reused although their catalytic activity descend gradually as a result of the decrease in their cobalt content.展开更多
Between all precursors of copper complex, bis-(acetylacetonato)-copper (II) and bis-oxalate copper (II) with very close structures are two of the best representatives for copper nanoparticles synthesis. In this resear...Between all precursors of copper complex, bis-(acetylacetonato)-copper (II) and bis-oxalate copper (II) with very close structures are two of the best representatives for copper nanoparticles synthesis. In this research, only bis-(acetylacetonato)-copper (II) in presence of some effective non-ionic surfactants such as Triton X-100, Dodecylamine, Tween 80 and also triphenylphosphine as a reducing agent via thermal decomposition process was used for copper nanopaticles synthesis. Two shif-base E19 and E22 complexes were also used for the investigation of these kinds of shif-base complexes capabilities by this method as precursors and all results were compared with each other. Between all surfactants, Triton X-100 gave the best yield with the largest grains. The techniques used for characterization of copper nanoparticles were TEM, EDX, FT-IR and XRD. TG-DTA and CV were used for characterization of bis-(acetylacetonato)-copper (II) complex.展开更多
Insulin resistance is characterized as one of crucial pathological changes in type 2 diabetes mellitus（T2DM）, and dyslipidaemia is frequently detected in T2DM. A variety of vanadium compounds have been studied as dr...Insulin resistance is characterized as one of crucial pathological changes in type 2 diabetes mellitus（T2DM）, and dyslipidaemia is frequently detected in T2DM. A variety of vanadium compounds have been studied as drug candidates for diabetes based on their insulin-like action. However, few studies focus on their antilipolytic effect. In the present study, we established an insulin-resistant model in 3T3-L1 adipocytes to mimic pathological conditions of T2DM according to a well-established method by the treatment of high concentrations of glucose and insulin, which was validated by oil red O staining and the decreased levels of phosphorylated Akt, AS160 and GSK3 after insulin treatment. The results demonstrated that bis（acetylacetonato）-oxidovanadium（Ⅳ）（VO（acac）_2） could inhibit isoproterenol-stimulated lipolysis through the reduction of the phosphorylated HSL and perilipin levels in both insulin-sensitive and insulin-resistant 3T3-L1 adipocytes. Moreover, although the levels of phosphorylated Akt induced by VO（acac）_2 were decreased, the rates of lipolytic inhibition were not significantly altered compared with those under insulin-sensitive condition, indicating that the anti-lipolytic effect of VO（acac）_2 might also function in an Akt-independent way in insulin-resistant adipocytes. Our work here help elucidate the anti-diabetic effects of vanadium compounds. It may not only shed light on the utility of vanadium-based compounds as potential anti-diabetic drugs but also serve as a useful screening model for new anti-diabetic drugs.展开更多
The title complex C24H38O14Yb2(Mr=896. 62 ) crystallized in orthorhombic system, space group Pbcn with unit cell dimensions a=13. 478 (4), b=16. 161(7), c=15. 110(5); V=3291. 2(2); Z=4; F(000) = 1736; Dc=1. 810g. cm-3...The title complex C24H38O14Yb2(Mr=896. 62 ) crystallized in orthorhombic system, space group Pbcn with unit cell dimensions a=13. 478 (4), b=16. 161(7), c=15. 110(5); V=3291. 2(2); Z=4; F(000) = 1736; Dc=1. 810g. cm-3;μ= 17. 5 cm-1 (MoKa). The final R and Rw are 0.061 and 0.058 respectively. The title complex is a bridged dimer. The ligands that bridge two Yb(Ⅲ) centerions are the two acetatos in the complex and every Yb(Ⅲ) ion is eight-coordinated, being bonded to one O atom of one H,O molecule, four O atoms of two acetylacetonatos,two O atoms of an acetato and one O atom of another acetato. The coordination polyhedron of the Yb(Ⅲ) ion in the title complex is a dodecahedron.展开更多
基金the National High Technology Research and Development Program of China(No. 2003AA321010)the Innovation Research Fund of Graduate University,Chinese Academy of Sciences(2006)
文摘Chelate tetra(acetylacetonato) tin(Ⅳ) was prepared and used as catalyst for polytrimethylene terephthalate synthesis.It exhibited higher catalytic activity than tetrabutyl titanate,butyltinhydroxide oxide and dibutyltin oxide.Decrease in reaction time, content of terminal carboxyl group,color intensity and increase in intrinsic viscosity were observed.The unique molecular structure can be considered as factor remarkably improving the catalytic activity of tetra(acetylacetonato) tin(Ⅳ).
文摘This paper reports mainly the preparation of silica supported acetylacetone ligands and their cobalt complexes, the characterization of their chemical structure, and the evaluation of their catalytic activity in the reaction for the preparation of ethers directly from alkanols and benzyl chloride. The results indicate that those silica supported β-diketone cobalt complexes (SACO) not only can simplify the reaction procedure of the ether preparation but also show a much higher catalytic activity in comparison with other homogeneous catalysts. In addition, SACO can be recovered and reused although their catalytic activity descend gradually as a result of the decrease in their cobalt content.
文摘Between all precursors of copper complex, bis-(acetylacetonato)-copper (II) and bis-oxalate copper (II) with very close structures are two of the best representatives for copper nanoparticles synthesis. In this research, only bis-(acetylacetonato)-copper (II) in presence of some effective non-ionic surfactants such as Triton X-100, Dodecylamine, Tween 80 and also triphenylphosphine as a reducing agent via thermal decomposition process was used for copper nanopaticles synthesis. Two shif-base E19 and E22 complexes were also used for the investigation of these kinds of shif-base complexes capabilities by this method as precursors and all results were compared with each other. Between all surfactants, Triton X-100 gave the best yield with the largest grains. The techniques used for characterization of copper nanoparticles were TEM, EDX, FT-IR and XRD. TG-DTA and CV were used for characterization of bis-(acetylacetonato)-copper (II) complex.
基金supported by National Natural Science Foundation of China(Grant No.21171011 and 21671009)
文摘Insulin resistance is characterized as one of crucial pathological changes in type 2 diabetes mellitus（T2DM）, and dyslipidaemia is frequently detected in T2DM. A variety of vanadium compounds have been studied as drug candidates for diabetes based on their insulin-like action. However, few studies focus on their antilipolytic effect. In the present study, we established an insulin-resistant model in 3T3-L1 adipocytes to mimic pathological conditions of T2DM according to a well-established method by the treatment of high concentrations of glucose and insulin, which was validated by oil red O staining and the decreased levels of phosphorylated Akt, AS160 and GSK3 after insulin treatment. The results demonstrated that bis（acetylacetonato）-oxidovanadium（Ⅳ）（VO（acac）_2） could inhibit isoproterenol-stimulated lipolysis through the reduction of the phosphorylated HSL and perilipin levels in both insulin-sensitive and insulin-resistant 3T3-L1 adipocytes. Moreover, although the levels of phosphorylated Akt induced by VO（acac）_2 were decreased, the rates of lipolytic inhibition were not significantly altered compared with those under insulin-sensitive condition, indicating that the anti-lipolytic effect of VO（acac）_2 might also function in an Akt-independent way in insulin-resistant adipocytes. Our work here help elucidate the anti-diabetic effects of vanadium compounds. It may not only shed light on the utility of vanadium-based compounds as potential anti-diabetic drugs but also serve as a useful screening model for new anti-diabetic drugs.
文摘The title complex C24H38O14Yb2(Mr=896. 62 ) crystallized in orthorhombic system, space group Pbcn with unit cell dimensions a=13. 478 (4), b=16. 161(7), c=15. 110(5); V=3291. 2(2); Z=4; F(000) = 1736; Dc=1. 810g. cm-3;μ= 17. 5 cm-1 (MoKa). The final R and Rw are 0.061 and 0.058 respectively. The title complex is a bridged dimer. The ligands that bridge two Yb(Ⅲ) centerions are the two acetatos in the complex and every Yb(Ⅲ) ion is eight-coordinated, being bonded to one O atom of one H,O molecule, four O atoms of two acetylacetonatos,two O atoms of an acetato and one O atom of another acetato. The coordination polyhedron of the Yb(Ⅲ) ion in the title complex is a dodecahedron.
