3,3＇-Bis（5-（N-（4-hydroxylphenyl）imidomethyl）pyrrol-2-yl）pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·（CH3OH）2, belongs to the orthorhombic system, space group ...3,3＇-Bis（5-（N-（4-hydroxylphenyl）imidomethyl）pyrrol-2-yl）pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·（CH3OH）2, belongs to the orthorhombic system, space group Pccn with a = 18.094（2）, b = 11.6890（16）, c = 13.3629（19） , V = 2826.3（7） 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F（000） = 1080 and μ（MoKα） = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ（I）, and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds.展开更多
A novel esterase Est C10 from B acillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of Est C10 was characterized. At present, the reports about the kinetic resolution of ra...A novel esterase Est C10 from B acillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of Est C10 was characterized. At present, the reports about the kinetic resolution of racemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase Est C10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate( R)-methyl 2-chloropropionate with high enantiomeric excess(>99%) after the optimization of process parameters such as p H, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration(80 mmol/L) of esterase Est C10 was higher than the kinetic resolution of another esterase, Est12-7(50 mmol/L). The novel microbial esterase Est C10 identified from the deep sea was a promising green biocatalyst in the generation of( R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.展开更多
Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedi...Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-（imidazol-2-methyl）propane and bib = 1,4-bis（imidazol-2-methyl）butane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional （2D） layered network with 3-connected （6,3） topology, which is further connected into a three- dimensional （3D） supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis（imidazol-2-methyl） ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature.展开更多
The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, ...The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol;and the reaction heat being 10.06 kJ·mol;. The dominant product predicted theoretically is in agreement with the experiment results.展开更多
The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Ab...The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.展开更多
Aluminum-promoted sulfated zirconia （ASZ） catalyst was prepared by impregnation of zirconium hydroxide with aqueous Al2（SO4）3 followed by calcinations. The characterization of these samples was carried out with va...Aluminum-promoted sulfated zirconia （ASZ） catalyst was prepared by impregnation of zirconium hydroxide with aqueous Al2（SO4）3 followed by calcinations. The characterization of these samples was carried out with various techniques such as X-ray powder diffraction （XRD）, N2 adsorption （BET）, NH3 temperature-programmed desorption （NH3-TPD）. The results indicated that the addition of aluminum has an effect on acid properties of the catalysts. Isomerization of n-pentane was carried out at 2.0 MP, WHSV 0.5 and H2/pentane molar ration of 4. In comparison to sulfated zirconia （SZ）, ASZ catalyst exhibited high catalytic activity and stability at low reaction temperature. In particular, when the reaction temperature was 120 ℃, the n-pentane conversion over ASZ remains at 80%, which is closed to its equilibrium conversion after running on stream for 6 h.展开更多
A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the s...A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the skeletal isomerization and the crack of n-pentane proceed simultaneously on WC-supported S_2O 2-_8/ZrO_2 catalyst. The addition of tungsten carbide showed a significant enhancement in the activity and stability of the catalyst for n-pentane isomerization. The catalyst showed evidently a better activity than S_2O 2-_8/ZrO_2 supported by Pt and WO_3. The results can be interpreted by the existence of the tungsten oxycarbide compound(WC_xO_y) with carbidic, oxide and acidic sites.展开更多
The crystal structure of the title compound（E）-ethyl 2-（4-（2,4-dimethoxy benzylide-neamino）-5-（3,4,5-trimethoxyphenyl）-4H-1,2,4-triazol-3-ylthio）acetate（4,C24H28N4O7S,Mr = 516.17） was synthesized and determi...The crystal structure of the title compound（E）-ethyl 2-（4-（2,4-dimethoxy benzylide-neamino）-5-（3,4,5-trimethoxyphenyl）-4H-1,2,4-triazol-3-ylthio）acetate（4,C24H28N4O7S,Mr = 516.17） was synthesized and determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 13.162（2）,b = 8.4506（13）,c = 22.602（4） ,β = 99.888（3）°,μ = 0.183 mm-1,V = 2476.5（7）3,Z = 4,Dc = 1.385 g/cm3,F（000） =1088,T = 110（2） K,R = 0.0426 and wR = 0.1216 for 3859 observed reflections with I 2σ（Ⅰ）.展开更多
基金supported by the National Natural Science Foundation of China (No. 20702038)
文摘3,3＇-Bis（5-（N-（4-hydroxylphenyl）imidomethyl）pyrrol-2-yl）pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·（CH3OH）2, belongs to the orthorhombic system, space group Pccn with a = 18.094（2）, b = 11.6890（16）, c = 13.3629（19） , V = 2826.3（7） 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F（000） = 1080 and μ（MoKα） = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ（I）, and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11030404)the Guangzhou Science and Technology Plan Projects(No.201510010012)the National Natural Science Foundation of China(No.21302199)
文摘A novel esterase Est C10 from B acillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of Est C10 was characterized. At present, the reports about the kinetic resolution of racemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase Est C10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate( R)-methyl 2-chloropropionate with high enantiomeric excess(>99%) after the optimization of process parameters such as p H, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration(80 mmol/L) of esterase Est C10 was higher than the kinetic resolution of another esterase, Est12-7(50 mmol/L). The novel microbial esterase Est C10 identified from the deep sea was a promising green biocatalyst in the generation of( R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.
基金supported by the National Natural Science of Foundation of China(No.21305060)
文摘Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-（imidazol-2-methyl）propane and bib = 1,4-bis（imidazol-2-methyl）butane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional （2D） layered network with 3-connected （6,3） topology, which is further connected into a three- dimensional （3D） supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis（imidazol-2-methyl） ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature.
基金Supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1601215)the Ministry of Education "Chunhui Plan"(Z2016177)
文摘The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol;and the reaction heat being 10.06 kJ·mol;. The dominant product predicted theoretically is in agreement with the experiment results.
文摘The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.
文摘Aluminum-promoted sulfated zirconia （ASZ） catalyst was prepared by impregnation of zirconium hydroxide with aqueous Al2（SO4）3 followed by calcinations. The characterization of these samples was carried out with various techniques such as X-ray powder diffraction （XRD）, N2 adsorption （BET）, NH3 temperature-programmed desorption （NH3-TPD）. The results indicated that the addition of aluminum has an effect on acid properties of the catalysts. Isomerization of n-pentane was carried out at 2.0 MP, WHSV 0.5 and H2/pentane molar ration of 4. In comparison to sulfated zirconia （SZ）, ASZ catalyst exhibited high catalytic activity and stability at low reaction temperature. In particular, when the reaction temperature was 120 ℃, the n-pentane conversion over ASZ remains at 80%, which is closed to its equilibrium conversion after running on stream for 6 h.
文摘A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the skeletal isomerization and the crack of n-pentane proceed simultaneously on WC-supported S_2O 2-_8/ZrO_2 catalyst. The addition of tungsten carbide showed a significant enhancement in the activity and stability of the catalyst for n-pentane isomerization. The catalyst showed evidently a better activity than S_2O 2-_8/ZrO_2 supported by Pt and WO_3. The results can be interpreted by the existence of the tungsten oxycarbide compound(WC_xO_y) with carbidic, oxide and acidic sites.
基金supported by the Science Foundation of the Southern Medical University for New Excellent Talents (No. B1000374)the Natural Science Foundation of Guangdong Province(No.10451051501004725)
文摘The crystal structure of the title compound（E）-ethyl 2-（4-（2,4-dimethoxy benzylide-neamino）-5-（3,4,5-trimethoxyphenyl）-4H-1,2,4-triazol-3-ylthio）acetate（4,C24H28N4O7S,Mr = 516.17） was synthesized and determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 13.162（2）,b = 8.4506（13）,c = 22.602（4） ,β = 99.888（3）°,μ = 0.183 mm-1,V = 2476.5（7）3,Z = 4,Dc = 1.385 g/cm3,F（000） =1088,T = 110（2） K,R = 0.0426 and wR = 0.1216 for 3859 observed reflections with I 2σ（Ⅰ）.
