A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cety...A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cetyltrimethylammonium bromide as the supramolecular template. The addition of HPWs to the synthesis mixture of hierarchical porous HKUST-1 results in the direct encapsulation of HPWs inside the mesopores of the HKUST-1 structure, with a homogeneous distribution over the HKUST-1 crystals, which is confirmed by XRD, FT-IR, N2 adsorption, UV-Vis DRS, and TEM. FT-IR-CO adsorption experiments indicated that additional Lewis acid sites were present in the HPWs@Meso-HKUST-1 sample. The novel heterogeneous catalyst demonstrates excellent catalytic performance for the selective oxidation of cyclopentene （CPE） to glutaraldehyde CGA） using tert-butyl hydroperoxide and acetonitrile （MeCN） as the oxidant and solvent, respectively. The high activity of the catalyst is attributed to the mesostructure of the catalyst and the nature and appropriate abundance of the HPWs--being highly dispersed with the addition of Lewis sites. After a reaction for 36 h, the 30% wt% HPWs@Meso-HKUST-1 catalyst exhibits a CPE conversion of 92.5% and a high GA yield of 73%. Furthermore, the HPWs@Meso-HKUST-1 material is sufficiently stable to prevent the leaching of HPWs, and behaves as a true heterogeneous catalyst that can be repeatedly recycled without sustaining a loss of activity and selectivity in the selective oxidation of CPE.展开更多
The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantl...The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantly improved the oxidation selectivity of cyclopentene. The effects of the reaction conditions on the conversion of cyclopentene were investigated in detail. The optimal reaction conditions are as follows: the H3PW12O40 to TBAB molar ratio, 1:1–1:3;H3PW12O40 to cyclopentene molar ratio,0.54:100–0.64:100;and molar ratio of H2O2 to cyclopentene, 1.6:1. The conversion reached to 59.8% in 4h at 35.0 ℃, while the selectivity of glutaraldehyde was 38.0% and the selectivity of 1,2-cyclopentanediol was 55.6%. In addition, a route for oxidation of cyclopentene by aqueous H2O2 using a heteropoly acid and quaternary ammonium salt as a phase transfer catalyst was proposed.展开更多
In this work, Pd–Cu/γ-Al2O3 is prepared by the impregnation method and investigated for selective oxygenization of cyclopentene to cyclopentanone. A series of bimetallic Pd–Cu/γ-Al_(2)O_(3) nanocatalysts were prep...In this work, Pd–Cu/γ-Al2O3 is prepared by the impregnation method and investigated for selective oxygenization of cyclopentene to cyclopentanone. A series of bimetallic Pd–Cu/γ-Al_(2)O_(3) nanocatalysts were prepared and the structures characterized by XRD, XPS and TEM. We determined that the obtained Pd–Cu/γ-Al_(2)O_(3)(molar ratio Pd:Cu = 5:1) was an efficient catalyst for the oxygenization of cyclopentene to cyclopentanone with 95% selectivity and 85% conversion(100 °C, 1 MPa initial O2 pressure, 7 h).展开更多
Tungsten-containing hexagonal mesoporous silica （W-HMS） supported tungsten oxide catalysts （WOx/W-HMS） was prepared for the selective oxidation of cyclopentene with aqueous hydrogen peroxide to glutaraldehyde. X-r...Tungsten-containing hexagonal mesoporous silica （W-HMS） supported tungsten oxide catalysts （WOx/W-HMS） was prepared for the selective oxidation of cyclopentene with aqueous hydrogen peroxide to glutaraldehyde. X-ray diffraction （XRD） results indicated that the crystal form of the active phase （tungsten oxide） of the WOx/W-HMS catalysts was dependent on the W loading and calcination temperature. X-ray photoelectron spec- troscopy （XPS） analysis revealed that the dispersed tungsten oxides on the surface of W-HMS support consisted of a mixture of W（V） and W（VI）. It was found that a high content of amorphous W species in （5＋） oxidation state resuited in the high catalytic activity. When the W loading was up to 12% （by mass） or the catalyst precursor was treated at temperature of 623 K, the catalytic activity decreased due to the presence of WO3 crystallites and the oxidation of W（V） to W（VI） on the catalyst surface. Furthermore, NH3-temperature-programmed-desorption （NH3-TPD） analysis showed that the effects of W loading and calcination temperature on the acidity of the catalysts were related to the catalytic activity. A high selectivity of 80.2% for glutaraldehyde with a complete conversion of cyclopentene was obtained over 8%WOx/W-HMS catalyst calcined at 573 K after 14 h of reaction.展开更多
Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
The development of polyoxometalates for olefin oxidation is critical to achieving the green chemical process of the C5 fraction further processing.Di-lacunary silicotungstic anions were easily obtained by continuously...The development of polyoxometalates for olefin oxidation is critical to achieving the green chemical process of the C5 fraction further processing.Di-lacunary silicotungstic anions were easily obtained by continuously adjusting the p H instead of the traditional step-by-step method,which exhibited excellent performance in the catalytic oxidation of cyclopentene(CPE)to aldehydes or alcohols.The 93.69%CPE conversion and 97.15%total product selectivity(41.38%for glutaraldehyde(GA)and 55.77%for 1,2-cyclopentanediol(1,2-diol)were achieved by using H_(2)O_(2)as the oxidant and acetonitrile as the solvent.Through complementary characterization,it was found that the optimized di-lacunary silicotungstic polyoxometalate retained a complete Keggin structure,and exhibited better catalytic activity and stability than the mono-lacunary or saturated silicodecatungstate because it exposed more catalytic active centers.Furthermore,in situ FT-IR spectra was utilized to monitor the reaction process,revealing the formation of the active species W(O_(2))on the di-lacunary silicotungstic polyoxometalate and the intermediate epoxycyclopentane during the catalytic oxidation of cyclopentene.展开更多
The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, M...The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, Mr = 473. 35) ismonoclinic with space group P21/c, a= 6. 923(1), b= 33. 178(5), c= 10. 644 (3)β=99. 86(2)°, V=2408. 8(8) A3, Z= 4, Dc= 1. 305g/cm3,μ(MoKa) = 3. 01cm-1,F(000) =984, R=0. 052, Rw=0. 067 for 2147 observed reflections (I】3(I)). Thephenyl groups and the alkoxy carbonyl group are in equatorial positions. The phenylgroups form dihedral angles bf 70. 67 and 66. 74° with the central five-membered ring.展开更多
The crystal and molecular structure of 4, 5-trans-2-amino-1, 3, 3-tri-cyano-4, 5-di(4-chlorophenyl) cyclopentene. ethanol - monohydrate has been deter-mined by X-ray diffraction method. The crystal (C20H12N4Cl2. C2H6O...The crystal and molecular structure of 4, 5-trans-2-amino-1, 3, 3-tri-cyano-4, 5-di(4-chlorophenyl) cyclopentene. ethanol - monohydrate has been deter-mined by X-ray diffraction method. The crystal (C20H12N4Cl2. C2H6O. H2O, Mr=443. 33) is triclinic with space group P1, a= 11. 033(4), b= 12. 199(3), c= 10. 732(3) A, a=114. 46(2), β=118. 33(3) γ=81. 56(3), V=1155- 1(7) A3, Z=2, Dc= 1. 275g/cm3, μ(MoKa) = 3. 05cm-1, F(000) = 460, R= 0. 070, Rw = 0. 089 for1965 observed reflections (I>3(I)). The phenyl groups are in equatorial positionsand form dihedral angles of 67. 89 and 63. 77° with the central 5-ring. X-ray analysisreveals that in the five membered ring the C (1) -C (2) bond is longer than normal double C=C bond while the C(2) -N (2) bond is shorter than normal C(sp)2-N bond.展开更多
The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, M...The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, Mr = 473. 35) ismonoclinic with space group P21/c, a= 6. 923(1), b= 33. 178(5), c= 10. 644 (3)β=99. 86(2)°, V=2408. 8(8) A3, Z= 4, Dc= 1. 305g/cm3,μ(MoKa) = 3. 01cm-1,F(000) =984, R=0. 052, Rw=0. 067 for 2147 observed reflections (I>3(I)). Thephenyl groups and the alkoxy carbonyl group are in equatorial positions. The phenylgroups form dihedral angles bf 70. 67 and 66. 74° with the central five-membered ring.展开更多
A facile iron-catalyzed C（sp3）-C（sp2） bond formation through DDQ-mediated cross-dehydrogenative homo-coupling of （E）-1,2-diarylprop-1-enes for the synthesis of highly aryl-substituted cyclopentenes has been deve...A facile iron-catalyzed C（sp3）-C（sp2） bond formation through DDQ-mediated cross-dehydrogenative homo-coupling of （E）-1,2-diarylprop-1-enes for the synthesis of highly aryl-substituted cyclopentenes has been developed.展开更多
Functionalized cyclopentenes could be prepared through Sm/TMSCl/t-BuOH mediated hydrodimerization cyclization of gem-diactivated alkene in one-pot at room temperature. The trans- or trans, transform isomer is in the m...Functionalized cyclopentenes could be prepared through Sm/TMSCl/t-BuOH mediated hydrodimerization cyclization of gem-diactivated alkene in one-pot at room temperature. The trans- or trans, transform isomer is in the majority and the major product was isolated from its stereoisomers through the fractional crystallization method.展开更多
The macrokinetics of hydrogenation of cyclopentadiene was investigated over Pd/γ-Al2O3 catalyst.Experimental results showed that the relationship between the constituents and reaction time was in agreement with the c...The macrokinetics of hydrogenation of cyclopentadiene was investigated over Pd/γ-Al2O3 catalyst.Experimental results showed that the relationship between the constituents and reaction time was in agreement with the characteristic of consecutive irreversible first-order reaction. Analysis on the reaction mechanism of selective hydrogenation of cyclopentadiene indicated that it is reasonable to express the hydrogenation rate of cyclopentadiene in the power law form. Parameters of the kinetic model were obtained by the Gauss-Newton method based on the experimental data. From the statistic test and residual error distribution the kinetic model was proved to be adequate.展开更多
Several γ-Al2O3 supported Pd-Ni bimetallic nanocatalysts （Pd-Ni （x：y）[Al2O3; where x and y represent the mass ratio of Pd and Ni, respectively） were prepared by the impregnation method and used for selective hyd...Several γ-Al2O3 supported Pd-Ni bimetallic nanocatalysts （Pd-Ni （x：y）[Al2O3; where x and y represent the mass ratio of Pd and Ni, respectively） were prepared by the impregnation method and used for selective hydrogenation of cyclopentadiene to cyclopentene. The Pd-NiJAl2O3 samples were confirmed to generate Pd-Ni bimetallic nanoparticles by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and transmission electron microscopy （TEM）. The catalytic activity was assessed in view of the effects of different mass ratios of Pd and Ni, temperature, pressure, etc. Among all the samples, the Pd-Ni （1：1 ）/Al2O3 （PN-1：1 ） catalyst showed extremely high catalytic ability. The conversion of cyclopentadiene and selectivity for cyclopentene can be simultaneously more than 90%.展开更多
Objective:To explore the main physiological mechanism of 15d-PGJ2 promoting periodontal tissue regeneration in patients with jaw defects caused by periodontal disease.Methods:From February 2016 to July 2019,a controll...Objective:To explore the main physiological mechanism of 15d-PGJ2 promoting periodontal tissue regeneration in patients with jaw defects caused by periodontal disease.Methods:From February 2016 to July 2019,a controlled study was conducted on 73 healthy residents(healthy group)and 73 patients(case group)with periodontal disease combined with jaw defects in Changsha medical university.T test was used to compare the growth factors of gingival crevicular fluid between the two groups.Peripheral blood cells;Cement-specific protein;Peripheral blood enzyme;Statistical differences in bone metabolites.The t test method compared the content of each index before and after treatment(15d-PGJ2 was treated at a dose of 200 mu/kg for 14 days).The method of factor analysis explores the internal correlation of each index.Result:RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were higher in the case group than in the healthy group.In the case group,RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were lower than those in the healthy group.The differences between the groups were statistically significant(P<0.05).Compared with before treatment,IL-1β,IL-17,Bfgf,YKL-40,BMP-2,ICTP,PICP,CTX were significantly decreased after treatment.RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were significantly increased.The differences were statistically significant(P<0.05).Factor analysis shows that four common factors can be extracted from 21 indicators,and the cumulative contribution rate is 96.993%.Conclusions:The treatment of 15d-PGJ2 in patients with periodontal disease with maxillary defects can significantly affect the expression of multiple characteristic indicators,which may involve four mechanisms:dysregulation of cell differentiation or migration,local inflammation or immune imbalance,destruction of alveolar bone microstructure,load or stimulation,and remodeling.The specific pathway related to this is still to be further explored.展开更多
in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 （20 mol%）, a [4 ＋ 1 ] annulation reaction...in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 （20 mol%）, a [4 ＋ 1 ] annulation reaction is realized between a series of l,l-dicyano-2,4-diaryl-1,3-dienes and ethoxycarbonyl-activated allylic acetate, producing polysubstituted cyclopentenes in modest to excellent yields. It is also observed that the substituents of both 1,3-dienes and allylic derivatives have a significant influence on the annulation mode： under the catalysis of PPh3 or PBu3 （20 mol%）, regioselective [3 ＋ 2] annulation products are formed from differently substituted substratcs.展开更多
基金supported by the Plan of Nature Science Fundamental Research in Henan University of Technology (2013JCYJ09)the Fundamental Research Funds for the Henan Provincial Colleges and Universities(2014YWQQ13)the National Natural Science Foundation of China (20903035,21373054)~~
文摘A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cetyltrimethylammonium bromide as the supramolecular template. The addition of HPWs to the synthesis mixture of hierarchical porous HKUST-1 results in the direct encapsulation of HPWs inside the mesopores of the HKUST-1 structure, with a homogeneous distribution over the HKUST-1 crystals, which is confirmed by XRD, FT-IR, N2 adsorption, UV-Vis DRS, and TEM. FT-IR-CO adsorption experiments indicated that additional Lewis acid sites were present in the HPWs@Meso-HKUST-1 sample. The novel heterogeneous catalyst demonstrates excellent catalytic performance for the selective oxidation of cyclopentene （CPE） to glutaraldehyde CGA） using tert-butyl hydroperoxide and acetonitrile （MeCN） as the oxidant and solvent, respectively. The high activity of the catalyst is attributed to the mesostructure of the catalyst and the nature and appropriate abundance of the HPWs--being highly dispersed with the addition of Lewis sites. After a reaction for 36 h, the 30% wt% HPWs@Meso-HKUST-1 catalyst exhibits a CPE conversion of 92.5% and a high GA yield of 73%. Furthermore, the HPWs@Meso-HKUST-1 material is sufficiently stable to prevent the leaching of HPWs, and behaves as a true heterogeneous catalyst that can be repeatedly recycled without sustaining a loss of activity and selectivity in the selective oxidation of CPE.
基金Supported by the National Natural Science Foundation of China(21406146)
文摘The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantly improved the oxidation selectivity of cyclopentene. The effects of the reaction conditions on the conversion of cyclopentene were investigated in detail. The optimal reaction conditions are as follows: the H3PW12O40 to TBAB molar ratio, 1:1–1:3;H3PW12O40 to cyclopentene molar ratio,0.54:100–0.64:100;and molar ratio of H2O2 to cyclopentene, 1.6:1. The conversion reached to 59.8% in 4h at 35.0 ℃, while the selectivity of glutaraldehyde was 38.0% and the selectivity of 1,2-cyclopentanediol was 55.6%. In addition, a route for oxidation of cyclopentene by aqueous H2O2 using a heteropoly acid and quaternary ammonium salt as a phase transfer catalyst was proposed.
基金financial assistance from the National Natural Science Foundation of China (Nos. 21272050, 21371044, 21472033 and 21571047)
文摘In this work, Pd–Cu/γ-Al2O3 is prepared by the impregnation method and investigated for selective oxygenization of cyclopentene to cyclopentanone. A series of bimetallic Pd–Cu/γ-Al_(2)O_(3) nanocatalysts were prepared and the structures characterized by XRD, XPS and TEM. We determined that the obtained Pd–Cu/γ-Al_(2)O_(3)(molar ratio Pd:Cu = 5:1) was an efficient catalyst for the oxygenization of cyclopentene to cyclopentanone with 95% selectivity and 85% conversion(100 °C, 1 MPa initial O2 pressure, 7 h).
文摘Tungsten-containing hexagonal mesoporous silica （W-HMS） supported tungsten oxide catalysts （WOx/W-HMS） was prepared for the selective oxidation of cyclopentene with aqueous hydrogen peroxide to glutaraldehyde. X-ray diffraction （XRD） results indicated that the crystal form of the active phase （tungsten oxide） of the WOx/W-HMS catalysts was dependent on the W loading and calcination temperature. X-ray photoelectron spec- troscopy （XPS） analysis revealed that the dispersed tungsten oxides on the surface of W-HMS support consisted of a mixture of W（V） and W（VI）. It was found that a high content of amorphous W species in （5＋） oxidation state resuited in the high catalytic activity. When the W loading was up to 12% （by mass） or the catalyst precursor was treated at temperature of 623 K, the catalytic activity decreased due to the presence of WO3 crystallites and the oxidation of W（V） to W（VI） on the catalyst surface. Furthermore, NH3-temperature-programmed-desorption （NH3-TPD） analysis showed that the effects of W loading and calcination temperature on the acidity of the catalysts were related to the catalytic activity. A high selectivity of 80.2% for glutaraldehyde with a complete conversion of cyclopentene was obtained over 8%WOx/W-HMS catalyst calcined at 573 K after 14 h of reaction.
基金Preject (No. 20072033) supported by the National Natural Science Foundation of China and Zhejiang Provincial Natural Science Foundation of China
文摘Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
基金the Science and Technology Project of Maoming(China)(200203094555139)for financial support。
文摘The development of polyoxometalates for olefin oxidation is critical to achieving the green chemical process of the C5 fraction further processing.Di-lacunary silicotungstic anions were easily obtained by continuously adjusting the p H instead of the traditional step-by-step method,which exhibited excellent performance in the catalytic oxidation of cyclopentene(CPE)to aldehydes or alcohols.The 93.69%CPE conversion and 97.15%total product selectivity(41.38%for glutaraldehyde(GA)and 55.77%for 1,2-cyclopentanediol(1,2-diol)were achieved by using H_(2)O_(2)as the oxidant and acetonitrile as the solvent.Through complementary characterization,it was found that the optimized di-lacunary silicotungstic polyoxometalate retained a complete Keggin structure,and exhibited better catalytic activity and stability than the mono-lacunary or saturated silicodecatungstate because it exposed more catalytic active centers.Furthermore,in situ FT-IR spectra was utilized to monitor the reaction process,revealing the formation of the active species W(O_(2))on the di-lacunary silicotungstic polyoxometalate and the intermediate epoxycyclopentane during the catalytic oxidation of cyclopentene.
文摘The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, Mr = 473. 35) ismonoclinic with space group P21/c, a= 6. 923(1), b= 33. 178(5), c= 10. 644 (3)β=99. 86(2)°, V=2408. 8(8) A3, Z= 4, Dc= 1. 305g/cm3,μ(MoKa) = 3. 01cm-1,F(000) =984, R=0. 052, Rw=0. 067 for 2147 observed reflections (I】3(I)). Thephenyl groups and the alkoxy carbonyl group are in equatorial positions. The phenylgroups form dihedral angles bf 70. 67 and 66. 74° with the central five-membered ring.
文摘The crystal and molecular structure of 4, 5-trans-2-amino-1, 3, 3-tri-cyano-4, 5-di(4-chlorophenyl) cyclopentene. ethanol - monohydrate has been deter-mined by X-ray diffraction method. The crystal (C20H12N4Cl2. C2H6O. H2O, Mr=443. 33) is triclinic with space group P1, a= 11. 033(4), b= 12. 199(3), c= 10. 732(3) A, a=114. 46(2), β=118. 33(3) γ=81. 56(3), V=1155- 1(7) A3, Z=2, Dc= 1. 275g/cm3, μ(MoKa) = 3. 05cm-1, F(000) = 460, R= 0. 070, Rw = 0. 089 for1965 observed reflections (I>3(I)). The phenyl groups are in equatorial positionsand form dihedral angles of 67. 89 and 63. 77° with the central 5-ring. X-ray analysisreveals that in the five membered ring the C (1) -C (2) bond is longer than normal double C=C bond while the C(2) -N (2) bond is shorter than normal C(sp)2-N bond.
文摘The crystal and molecular structure of 3,4-trans-4, 5-trans-2-amino-3cyano-1, 3-diethyloxy carbonyl-4, 5-di (4-chlorophenyl ) cyclopentene has been determined by X-ray diffraction method. The crystal (C24H22O4N2Cl2, Mr = 473. 35) ismonoclinic with space group P21/c, a= 6. 923(1), b= 33. 178(5), c= 10. 644 (3)β=99. 86(2)°, V=2408. 8(8) A3, Z= 4, Dc= 1. 305g/cm3,μ(MoKa) = 3. 01cm-1,F(000) =984, R=0. 052, Rw=0. 067 for 2147 observed reflections (I>3(I)). Thephenyl groups and the alkoxy carbonyl group are in equatorial positions. The phenylgroups form dihedral angles bf 70. 67 and 66. 74° with the central five-membered ring.
基金supported by the Natural Science Foundation of China （No. 20972047）, the ‘Shu Guang＇ project of Shanghai Municipal Education Commission, Shanghai Education Development Foundation （No. 09SG28）, the Fundamental Research Funds for the Central Universities and the Shanghai Committee of Science and Technology （No. 11DZ2260600）.
文摘A facile iron-catalyzed C（sp3）-C（sp2） bond formation through DDQ-mediated cross-dehydrogenative homo-coupling of （E）-1,2-diarylprop-1-enes for the synthesis of highly aryl-substituted cyclopentenes has been developed.
基金Project (No. 29872010) supported by the National Natural Science Foundation of China, the NSF of Zhejiang Province, Chinathe laboratory of Organometallic chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences.
文摘Functionalized cyclopentenes could be prepared through Sm/TMSCl/t-BuOH mediated hydrodimerization cyclization of gem-diactivated alkene in one-pot at room temperature. The trans- or trans, transform isomer is in the majority and the major product was isolated from its stereoisomers through the fractional crystallization method.
文摘The macrokinetics of hydrogenation of cyclopentadiene was investigated over Pd/γ-Al2O3 catalyst.Experimental results showed that the relationship between the constituents and reaction time was in agreement with the characteristic of consecutive irreversible first-order reaction. Analysis on the reaction mechanism of selective hydrogenation of cyclopentadiene indicated that it is reasonable to express the hydrogenation rate of cyclopentadiene in the power law form. Parameters of the kinetic model were obtained by the Gauss-Newton method based on the experimental data. From the statistic test and residual error distribution the kinetic model was proved to be adequate.
基金the financial assistance from the National Natural Science Foundation of China (Nos.21272050,21371044,21472033)the Program for New Century Excellent Talents in University of the Chinese Ministry of Education (No.NCET-110627)
文摘Several γ-Al2O3 supported Pd-Ni bimetallic nanocatalysts （Pd-Ni （x：y）[Al2O3; where x and y represent the mass ratio of Pd and Ni, respectively） were prepared by the impregnation method and used for selective hydrogenation of cyclopentadiene to cyclopentene. The Pd-NiJAl2O3 samples were confirmed to generate Pd-Ni bimetallic nanoparticles by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and transmission electron microscopy （TEM）. The catalytic activity was assessed in view of the effects of different mass ratios of Pd and Ni, temperature, pressure, etc. Among all the samples, the Pd-Ni （1：1 ）/Al2O3 （PN-1：1 ） catalyst showed extremely high catalytic ability. The conversion of cyclopentadiene and selectivity for cyclopentene can be simultaneously more than 90%.
基金Hunan university students’innovation and entrepreneurship training program(No.[2019]191-2440)Zhejiang provincial natural fund(No.GF18H140006)。
文摘Objective:To explore the main physiological mechanism of 15d-PGJ2 promoting periodontal tissue regeneration in patients with jaw defects caused by periodontal disease.Methods:From February 2016 to July 2019,a controlled study was conducted on 73 healthy residents(healthy group)and 73 patients(case group)with periodontal disease combined with jaw defects in Changsha medical university.T test was used to compare the growth factors of gingival crevicular fluid between the two groups.Peripheral blood cells;Cement-specific protein;Peripheral blood enzyme;Statistical differences in bone metabolites.The t test method compared the content of each index before and after treatment(15d-PGJ2 was treated at a dose of 200 mu/kg for 14 days).The method of factor analysis explores the internal correlation of each index.Result:RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were higher in the case group than in the healthy group.In the case group,RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were lower than those in the healthy group.The differences between the groups were statistically significant(P<0.05).Compared with before treatment,IL-1β,IL-17,Bfgf,YKL-40,BMP-2,ICTP,PICP,CTX were significantly decreased after treatment.RANKL,ICAM-1,TGF-β1,Th17,Treg,PDLSCs,SOST,CAP,HMGB1,CTSK,5-LOX,COX-2,NTX were significantly increased.The differences were statistically significant(P<0.05).Factor analysis shows that four common factors can be extracted from 21 indicators,and the cumulative contribution rate is 96.993%.Conclusions:The treatment of 15d-PGJ2 in patients with periodontal disease with maxillary defects can significantly affect the expression of multiple characteristic indicators,which may involve four mechanisms:dysregulation of cell differentiation or migration,local inflammation or immune imbalance,destruction of alveolar bone microstructure,load or stimulation,and remodeling.The specific pathway related to this is still to be further explored.
基金Acknowledgement Financial support from National Natural Science Foundation of China （Nos. 21072100 21121002 21272119） is gratefully acknowledged.
文摘in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 （20 mol%）, a [4 ＋ 1 ] annulation reaction is realized between a series of l,l-dicyano-2,4-diaryl-1,3-dienes and ethoxycarbonyl-activated allylic acetate, producing polysubstituted cyclopentenes in modest to excellent yields. It is also observed that the substituents of both 1,3-dienes and allylic derivatives have a significant influence on the annulation mode： under the catalysis of PPh3 or PBu3 （20 mol%）, regioselective [3 ＋ 2] annulation products are formed from differently substituted substratcs.
