A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic in...A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic intermediate7h,the key B/C rings in brazilin core could be constructed by the sequential of Friedel-Crafts/Ullmann-Ma rather than Ullmann-Ma/Friedel-Crafts reactions.展开更多
Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discusse...Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discussed.The results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.展开更多
Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. De...Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. Depolymerization was made by two methods： （1） reaction oflignin with NaOH 2%; （2） exposition oflignin to UV beam for 6, 12, 24, 36, 48 and 60 hours. The best depolimerization result was with exposition of lignin to UV by 12 hours since phenylpropanoic structure with higher number of free positions （unoccupied carbons） in C3 and C5 of its aromatic ring was obtained. It is known by Mannich Reaction and determination of phenolic OH by UV analysis. Later, its reactivity was increased by hydroxymethylation process by means of reaction of depolymerizated product with formaldehyde and later with glyoxal since it is less toxic. The modified product was mixed with six different kinds of resins （phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, Glyoxal-formaldehyde, urea-formaldehyde and melamine-formaldehyde） to obtain a better mechanical characteristic as a synthetic wood. The best result was the one with melamine-formaldehyde. Finally, this product was mixed with testa rice so final product showed a great hardness and a shinny and smooth appearance.展开更多
Objective： Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization i...Objective： Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods： Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein （EGFP） tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay （EMSA） and chromatin immunoprecipitation assay （CHIP）. Results： Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions： Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.展开更多
Non-a-tocopherols are hydroxymethylated and hydrogenated to produce α-tocopherol in one pot process by simultaneously reacting with paraformaldehyde and hydrogen in the presence of catalysts of benzenesulfonic acid a...Non-a-tocopherols are hydroxymethylated and hydrogenated to produce α-tocopherol in one pot process by simultaneously reacting with paraformaldehyde and hydrogen in the presence of catalysts of benzenesulfonic acid and 5% Pd/C in an autoclave. Effects of various operation conditions have been studied. The preferable reaction conditions are: temperature 180 ℃ to 200 ℃, pressure 5.0 MPa, acid concentration 0.5 g/100 ml ethanol, mass ratio of Pd/C to tocopherols 7.1 g/100 g, and reaction time 5.0 h. A product with α-tocopherol content of 80% was obtained by using a raw material with a total tocopherols content of 80.54%. The conversion of non-α-tocopherols is almost 100%, and the mole yield of a-tocopherol is more than 90%.展开更多
The global burden of psychopathologies appears to be underestimated,since the global psychiatric disorder burden is exceeding other medical burdens.To be able to address this problem more effectively,we need to better...The global burden of psychopathologies appears to be underestimated,since the global psychiatric disorder burden is exceeding other medical burdens.To be able to address this problem more effectively,we need to better understand the etiology of psychiatric disorders.One of the hallmarks of psychiatric disorders appears to be epigenetic dysregulation.While some epigenetic modifications(such as DNA methylation)are well known and studied,the roles of others have been investigated much less.DNA hydroxymethylation is a rarely studied epigenetic modification,which as well as being an intermediate stage in the DNA demethylation cycle is also an independent steady cell state involved in neurodevelopment and plasticity.In contrast to DNA methylation,DNA hydroxymethylation appears to be related to an increase in gene expression and subsequent protein expression.Although no particular gene or genetic locus can be at this point linked to changes in DNA hydroxymethylation in psychiatric disorders,the epigenetic marks present good potential for biomarker identification because the epigenetic landscape is a result of the interplay between genes and environment,which both influence the development of psychiatric disorders,and because hydoxymethylation changes are particularly enriched in the brain and in synapse-related genes.展开更多
The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexat...The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.展开更多
A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis（hydroxymethyl）phenol（BBHMP）,which is a simple and available phenolic receptor the abs...A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis（hydroxymethyl）phenol（BBHMP）,which is a simple and available phenolic receptor the absence of any special chromophoric function and with over wide range of anions（Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-） in DMSO media.The colorimetric method is described for naked-eye detection of F^- in the presence of the BBHMP.The BBHMP was found to show selective and sensitive fluorescence quenching response toward fluoride over than Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-.展开更多
2,3-Bis（hydroxymethyl）-2,3-dinitro-1,4-butanediol（C6H12N2O8） was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the t...2,3-Bis（hydroxymethyl）-2,3-dinitro-1,4-butanediol（C6H12N2O8） was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324（2）,b = 0.6454（3）,c = 0.7062（3） nm,α= 111.550（4）,β= 95.505（4）,γ= 113.395（4）°,V = 0.23595（16） nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F（000） = 126,R = 0.0304 and wR = 0.0907.展开更多
The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under...The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under ambient pressure,the modified carbon nanotube‐supported Pd‐based catalysts demonstrate the maximum FDCA yield of 93.0%with a full conversion of BHMF after 60 min at 60°C,much superior to that of the traditional route using 5‐hydroxymethylfurfural(HMF)as substrates(only a yield of 35.7%).The participation of PdH_(x) active species with metallic Pd can be responsible for the encouraging performance.Meanwhile,a possible reaction pathway proceeding through 2,5‐diformylfuran(DFF)and 5‐formyl‐2‐furancarboxylic acid(FFCA)as process intermediates is suggested for BHMF route.The present work may provide new opportunities to synthesize other high value‐added oxygenates by using BHMF as an alternative feedstock.展开更多
5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated...5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source.展开更多
The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymeth...The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymethyl-2-furancarboxylic acid(HMFCA),formyl 2-furancarboxylic acid(FFCA),2,5-furandicarboxylic acid(FDCA) and furan-2,5-dimethylcarboxylate(FDMC).These products have been extensively employed to fabricate novel polymers,pharmaceuticals,sustainable dyes and many other value-added fine chemicals.The heart of the developed HMF oxidation processes is always the catalyst.In this regard,this review comprehensively summarized the established heterogeneous catalyst design strategy for the selective oxidation of HMF via thermo-catalysis.Particular attention has been focused on the reaction mechanism of HMF oxidation over different catalysts as well as enhancing the catalytic performance of the catalyst through manipulating the properties of the support and fabricating of multi-component metal nano-particles and oxides.The current challenges and possible research directions for the catalytic oxidation of HMF in the future are also discussed.展开更多
5-（Hydroxymethyl） isophthalic acid （H2HIA） as a novel organic ligand was prepared from 3,5-bis（methoxycarbonyl）benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold inter...5-（Hydroxymethyl） isophthalic acid （H2HIA） as a novel organic ligand was prepared from 3,5-bis（methoxycarbonyl）benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold interpenetration structure, namely [Zn1/2（HIA）1/2（DPEE）1/2]n （1）, was hydrothermally synthesized at 160 ℃, using H2HIA ligands to assemble with DPEE ligands and Zn2＋ ions. Complex 1 crystalizes in orthorhombic system, space group Pnna, with a = 8.2118（5）, b = 17.1698（7）, c =14.9922（7） ？, V = 2113.82（18） ？3, μ = 1.194 mm-1, Z = 4 and S = 0.967. Moreover, some physical characteristics of complex 1, such as powder X-ray diffraction （PXRD）, thermogravimetry analyses （TGA） and photoluminescent properties, were also investigated.展开更多
The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the prese...The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the presence of p-toluenesulfonic acid,and characterized by IR,1H-NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic system,space group C2/c with a = 25.133（2）,b = 5.7219（5）,c = 21.942（2）（A°） ,β = 99.145（2）°,V = 3115.3（5）（A°）^3,Z = 8,Dc = 1.340 g/cm^3,Mr = 314.33,F（000） = 1328,μ = 0.097 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0352 and wR = 0.1022 for 2486 observed reflections with I 〉 2σ（I）.X-ray analysis reveals that the two 1,3-dioxane rings passing through the central spiro-C atom both adopt chair conformation.Intermolecular C-H…π,C-H…O and C-H…N weak interactions link the molecules to form a three-dimensional samdwich,which are effective in the stabilization of the crystal structure.展开更多
基金support from National Natural Science Foundation of China(82260683 and 22267024)Scientific and Technological Project of Yunnan Precious Metals Laboratory(YPML-2023050265 and YPML-2023050217)+3 种基金Yunnan Science and Technology Talent and Platform Program(202105AG070012)the Top Young Talent of Ten Thousand Talents Program of Yunnan Province(D.L.and L.-D.S.)the Start-up Fund of Yunnan University of Chinese Medicine(2019YZG03)the Bioactive Ethnopharmacol Molecules Chemical Conversion and Application Innovation Team of Department of Education of Yunnan Province(2022).
文摘A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic intermediate7h,the key B/C rings in brazilin core could be constructed by the sequential of Friedel-Crafts/Ullmann-Ma rather than Ullmann-Ma/Friedel-Crafts reactions.
基金supported by Natural Science Foundation of Xuzhou Normal University(No.08XLB08)Science and Technology Project of Xuzhou(No.XJ09078)Universities Natural Science Foundation of Jiangsu Province (No.09KJD 150006)
文摘Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discussed.The results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.
文摘Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. Depolymerization was made by two methods： （1） reaction oflignin with NaOH 2%; （2） exposition oflignin to UV beam for 6, 12, 24, 36, 48 and 60 hours. The best depolimerization result was with exposition of lignin to UV by 12 hours since phenylpropanoic structure with higher number of free positions （unoccupied carbons） in C3 and C5 of its aromatic ring was obtained. It is known by Mannich Reaction and determination of phenolic OH by UV analysis. Later, its reactivity was increased by hydroxymethylation process by means of reaction of depolymerizated product with formaldehyde and later with glyoxal since it is less toxic. The modified product was mixed with six different kinds of resins （phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, Glyoxal-formaldehyde, urea-formaldehyde and melamine-formaldehyde） to obtain a better mechanical characteristic as a synthetic wood. The best result was the one with melamine-formaldehyde. Finally, this product was mixed with testa rice so final product showed a great hardness and a shinny and smooth appearance.
基金supported by National Basic Research Program of China(Grant No.2011CB504201)
文摘Objective： Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods： Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein （EGFP） tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay （EMSA） and chromatin immunoprecipitation assay （CHIP）. Results： Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions： Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.
文摘Non-a-tocopherols are hydroxymethylated and hydrogenated to produce α-tocopherol in one pot process by simultaneously reacting with paraformaldehyde and hydrogen in the presence of catalysts of benzenesulfonic acid and 5% Pd/C in an autoclave. Effects of various operation conditions have been studied. The preferable reaction conditions are: temperature 180 ℃ to 200 ℃, pressure 5.0 MPa, acid concentration 0.5 g/100 ml ethanol, mass ratio of Pd/C to tocopherols 7.1 g/100 g, and reaction time 5.0 h. A product with α-tocopherol content of 80% was obtained by using a raw material with a total tocopherols content of 80.54%. The conversion of non-α-tocopherols is almost 100%, and the mole yield of a-tocopherol is more than 90%.
基金Supported by Slovenian Research Agency,Young Researcher Grant toŠalamon Arčan I,No.P1-0390,J3-4533,Z3-2653.
文摘The global burden of psychopathologies appears to be underestimated,since the global psychiatric disorder burden is exceeding other medical burdens.To be able to address this problem more effectively,we need to better understand the etiology of psychiatric disorders.One of the hallmarks of psychiatric disorders appears to be epigenetic dysregulation.While some epigenetic modifications(such as DNA methylation)are well known and studied,the roles of others have been investigated much less.DNA hydroxymethylation is a rarely studied epigenetic modification,which as well as being an intermediate stage in the DNA demethylation cycle is also an independent steady cell state involved in neurodevelopment and plasticity.In contrast to DNA methylation,DNA hydroxymethylation appears to be related to an increase in gene expression and subsequent protein expression.Although no particular gene or genetic locus can be at this point linked to changes in DNA hydroxymethylation in psychiatric disorders,the epigenetic marks present good potential for biomarker identification because the epigenetic landscape is a result of the interplay between genes and environment,which both influence the development of psychiatric disorders,and because hydoxymethylation changes are particularly enriched in the brain and in synapse-related genes.
文摘The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.
文摘A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis（hydroxymethyl）phenol（BBHMP）,which is a simple and available phenolic receptor the absence of any special chromophoric function and with over wide range of anions（Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-） in DMSO media.The colorimetric method is described for naked-eye detection of F^- in the presence of the BBHMP.The BBHMP was found to show selective and sensitive fluorescence quenching response toward fluoride over than Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-.
基金Supported by the National "973" project (No. 613740102)
文摘2,3-Bis（hydroxymethyl）-2,3-dinitro-1,4-butanediol（C6H12N2O8） was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324（2）,b = 0.6454（3）,c = 0.7062（3） nm,α= 111.550（4）,β= 95.505（4）,γ= 113.395（4）°,V = 0.23595（16） nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F（000） = 126,R = 0.0304 and wR = 0.0907.
文摘The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under ambient pressure,the modified carbon nanotube‐supported Pd‐based catalysts demonstrate the maximum FDCA yield of 93.0%with a full conversion of BHMF after 60 min at 60°C,much superior to that of the traditional route using 5‐hydroxymethylfurfural(HMF)as substrates(only a yield of 35.7%).The participation of PdH_(x) active species with metallic Pd can be responsible for the encouraging performance.Meanwhile,a possible reaction pathway proceeding through 2,5‐diformylfuran(DFF)and 5‐formyl‐2‐furancarboxylic acid(FFCA)as process intermediates is suggested for BHMF route.The present work may provide new opportunities to synthesize other high value‐added oxygenates by using BHMF as an alternative feedstock.
基金financially supported by the National Key R&D Program of China 2021YFC2101604)the National Natural Science Foundation of China(22278339,21978248)+1 种基金the Guangdong Provincial Key Research and Development Program(2020B0101070001)the Natural Science Foundation of Fujian Province of China(2019J06005)。
文摘5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source.
基金funding supported by the National Natural Science Foundation of China (Grant Nos. 2207827521978246)+3 种基金the National Key Research and Development Program of China (Grant No. 2019YFB1503903)the Key Area Research and Development Program of Guangdong Province (Grant No. 2020B0101070001)the Fundamental Research Funds for the Central Universities (Grant No. 20720190014)PetroChina Innovation Foundation (2019D5007-0413)。
文摘The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymethyl-2-furancarboxylic acid(HMFCA),formyl 2-furancarboxylic acid(FFCA),2,5-furandicarboxylic acid(FDCA) and furan-2,5-dimethylcarboxylate(FDMC).These products have been extensively employed to fabricate novel polymers,pharmaceuticals,sustainable dyes and many other value-added fine chemicals.The heart of the developed HMF oxidation processes is always the catalyst.In this regard,this review comprehensively summarized the established heterogeneous catalyst design strategy for the selective oxidation of HMF via thermo-catalysis.Particular attention has been focused on the reaction mechanism of HMF oxidation over different catalysts as well as enhancing the catalytic performance of the catalyst through manipulating the properties of the support and fabricating of multi-component metal nano-particles and oxides.The current challenges and possible research directions for the catalytic oxidation of HMF in the future are also discussed.
基金supported by the Natural Science Foundation of Guizhou Province(20122344)125 program of Guizhou Education Department(2012015)the Doctoral Scientific Fund of Zunyi Normal College(2012BSJJ12)
文摘5-（Hydroxymethyl） isophthalic acid （H2HIA） as a novel organic ligand was prepared from 3,5-bis（methoxycarbonyl）benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold interpenetration structure, namely [Zn1/2（HIA）1/2（DPEE）1/2]n （1）, was hydrothermally synthesized at 160 ℃, using H2HIA ligands to assemble with DPEE ligands and Zn2＋ ions. Complex 1 crystalizes in orthorhombic system, space group Pnna, with a = 8.2118（5）, b = 17.1698（7）, c =14.9922（7） ？, V = 2113.82（18） ？3, μ = 1.194 mm-1, Z = 4 and S = 0.967. Moreover, some physical characteristics of complex 1, such as powder X-ray diffraction （PXRD）, thermogravimetry analyses （TGA） and photoluminescent properties, were also investigated.
基金supported by the National Natural Science Foundation of China (No. 20872051 and 21002009)the Scientific and Technological Project of Changzhou (CJ20115019)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the presence of p-toluenesulfonic acid,and characterized by IR,1H-NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic system,space group C2/c with a = 25.133（2）,b = 5.7219（5）,c = 21.942（2）（A°） ,β = 99.145（2）°,V = 3115.3（5）（A°）^3,Z = 8,Dc = 1.340 g/cm^3,Mr = 314.33,F（000） = 1328,μ = 0.097 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0352 and wR = 0.1022 for 2486 observed reflections with I 〉 2σ（I）.X-ray analysis reveals that the two 1,3-dioxane rings passing through the central spiro-C atom both adopt chair conformation.Intermolecular C-H…π,C-H…O and C-H…N weak interactions link the molecules to form a three-dimensional samdwich,which are effective in the stabilization of the crystal structure.
