Studies on the degradation process of waste polyethylene terephthalate(PET)have become increasingly mature,but there are relatively few studies on the separation of degradation products.The products contain many compo...Studies on the degradation process of waste polyethylene terephthalate(PET)have become increasingly mature,but there are relatively few studies on the separation of degradation products.The products contain many components and the separation of which is difficult.Therefore,the study on phase equilibrium thermodynamics of bis-2-hydroxyethyl terephthalate(BHET)is of great theoretical significance and practical value to provide basic data for the BHET crystallization separation.In this work,the degraded products were purified and characterized.The solubility of BHET in methanol,ethanol,ethylene glycol,water and the mixture of ethylene glycol+water were determined by static method.The experimental results were correlated with different models,such as ideal solution(IS)model,λh equation,Apelblat equation and NRTL model.Based on the van’t Hoff equation,the mixing Gibbs energy,enthalpy and entropy were calculated.From this work,the basic data which can be used to guide the crystallization process of BHET were obtained,including solubility data,correlation model and thermodynamic properties.展开更多
Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as ...Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as the catalysts for the synthesis of bisdihydropyrimidin -2(1H)-ones from aromatic dialdehydes,1,3-dicarbonyl compounds and urea at 90℃under solvent-free conditions.展开更多
The title compound 1 was synthesized from 1.2:5,6-dianhydro-3,4-dianhydro-3,4-isopropylideneD-mannitol 2 through four steps in a total yield of 53%. The absolute configuration of this compound was confirmed by X-ray d...The title compound 1 was synthesized from 1.2:5,6-dianhydro-3,4-dianhydro-3,4-isopropylideneD-mannitol 2 through four steps in a total yield of 53%. The absolute configuration of this compound was confirmed by X-ray diffraction.展开更多
The geometric conformation and electronic structure of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(Ⅲ) perchlorate and its Ni/Fe/Cu/Zn analogues are studied under the TPSS (Tao-Perdew-Staroverov-Scuseria) ...The geometric conformation and electronic structure of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(Ⅲ) perchlorate and its Ni/Fe/Cu/Zn analogues are studied under the TPSS (Tao-Perdew-Staroverov-Scuseria) levels of density functional theory in order to throw light on the relationship between their energy gaps and impact sensitivity While the perchlorate ions are coordinated with the copper cation, which is different from the other four compounds NBO (Natural bond orbital) analyses indicated that the metal-ligand interaction in the Co complex is covalent, while the others are ionic. The analysis of the electrostatic potential demonstrated that the O atoms from the nitro-tetrazole ring and perchlorate were primarily negative, while the other atoms were positive. The study was also conducted to gain a better understanding of the correlation of the energy gap and impact sensitivity.展开更多
A series of(Z)-2-chloro-1,3-diarylpropen-1-ones were unexpectedly synthesized in moderate yields by treatment of easily available 2,3-epoxy-1,3-diarylpropan-1-ones with Vilsmeier reagent,which was derived from bis(...A series of(Z)-2-chloro-1,3-diarylpropen-1-ones were unexpectedly synthesized in moderate yields by treatment of easily available 2,3-epoxy-1,3-diarylpropan-1-ones with Vilsmeier reagent,which was derived from bis(trichloromethyl) carbonate(BTC, triphosgene) and DMF.A possible mechanism was also proposed,where sequential ring-opening,halogenation and elimination reactions were involved.展开更多
A series of new chiral 2(5H)-furanone derivatives containing bis-l,2,3-triazole moiety were designed and syn- thesized from (5S)-5-alkoxy-3,4-dihalo-2(5H)-furanones 1, dicarboxyl amino acids 2, propargyl bromide...A series of new chiral 2(5H)-furanone derivatives containing bis-l,2,3-triazole moiety were designed and syn- thesized from (5S)-5-alkoxy-3,4-dihalo-2(5H)-furanones 1, dicarboxyl amino acids 2, propargyl bromide, and or- ganic azides 5 under mild conditions via the sequential three steps, including asymmetric Michael addi- tion-elimination, substitution and no-ligand click reaction. Twelve new intermediates, including N-[5-alkoxy- 2(5H)-furanonyl] dicarboxyl amino acids 3 and their corresponding propargyl esters 4, and twelve target molecules 6 were characterized by FTIR, 1H NMR, 13C NMR, MS and elemental analysis. The influences of different syn- thetic conditions and substrates in each step were investigated. The research provides a new method and idea for the synthesis of 2(5H)-furanone compounds with polyheterocyclic structure due to the diversities of four basic unit molecules.展开更多
Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). Th...Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses.展开更多
A novel route for the synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2,ones from acetylated 2- aminothiazoles and 2-aminopyridines under Vilsmeier conditions has been developed. The plausible ...A novel route for the synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2,ones from acetylated 2- aminothiazoles and 2-aminopyridines under Vilsmeier conditions has been developed. The plausible mechanism has also been proposed.展开更多
基金financially supported by the National Key Research and Development Program of China(2019YFC1908204)the National Natural Scientific Fund of China(No.21878292,21776289,21908232,21978291)+1 种基金Innovation Academy forGreen Manufacture,Chinese Academy of Sciences(No.IAGM2020C12,IAGM2020C21 and IAGM-2019-A06)K.C.Wong Education Foundation(No.GJTD-2018-04)。
文摘Studies on the degradation process of waste polyethylene terephthalate(PET)have become increasingly mature,but there are relatively few studies on the separation of degradation products.The products contain many components and the separation of which is difficult.Therefore,the study on phase equilibrium thermodynamics of bis-2-hydroxyethyl terephthalate(BHET)is of great theoretical significance and practical value to provide basic data for the BHET crystallization separation.In this work,the degraded products were purified and characterized.The solubility of BHET in methanol,ethanol,ethylene glycol,water and the mixture of ethylene glycol+water were determined by static method.The experimental results were correlated with different models,such as ideal solution(IS)model,λh equation,Apelblat equation and NRTL model.Based on the van’t Hoff equation,the mixing Gibbs energy,enthalpy and entropy were calculated.From this work,the basic data which can be used to guide the crystallization process of BHET were obtained,including solubility data,correlation model and thermodynamic properties.
文摘Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as the catalysts for the synthesis of bisdihydropyrimidin -2(1H)-ones from aromatic dialdehydes,1,3-dicarbonyl compounds and urea at 90℃under solvent-free conditions.
文摘The title compound 1 was synthesized from 1.2:5,6-dianhydro-3,4-dianhydro-3,4-isopropylideneD-mannitol 2 through four steps in a total yield of 53%. The absolute configuration of this compound was confirmed by X-ray diffraction.
基金Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cjoc.201280027 or from the author. Acknowledgment We gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 10776002) and China Academy of Engineering Physics (No. 20911120033), the project of State Key Laboratory of Science and Technology (Nos. QNKT11-06, YBKT10-03), and the Program for New Centu17 Excellent Talents in University (No. NCET-09-005I). Our thanks are due to Professor Gustavo E. Scuseria for providing the development version of Gaussian program.
文摘The geometric conformation and electronic structure of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(Ⅲ) perchlorate and its Ni/Fe/Cu/Zn analogues are studied under the TPSS (Tao-Perdew-Staroverov-Scuseria) levels of density functional theory in order to throw light on the relationship between their energy gaps and impact sensitivity While the perchlorate ions are coordinated with the copper cation, which is different from the other four compounds NBO (Natural bond orbital) analyses indicated that the metal-ligand interaction in the Co complex is covalent, while the others are ionic. The analysis of the electrostatic potential demonstrated that the O atoms from the nitro-tetrazole ring and perchlorate were primarily negative, while the other atoms were positive. The study was also conducted to gain a better understanding of the correlation of the energy gap and impact sensitivity.
基金the National Natural Science Foundation of China(Nos.20806073 and 20876147)the National Key Technology Research and Development Program(No.2007BAI34B06) for financial support
文摘A series of(Z)-2-chloro-1,3-diarylpropen-1-ones were unexpectedly synthesized in moderate yields by treatment of easily available 2,3-epoxy-1,3-diarylpropan-1-ones with Vilsmeier reagent,which was derived from bis(trichloromethyl) carbonate(BTC, triphosgene) and DMF.A possible mechanism was also proposed,where sequential ring-opening,halogenation and elimination reactions were involved.
基金We are grateful to the National Natural Science Foundation of China (No. 20772035), the Third Talents Special Funds of Guangdong Higher Education (No. Guangdong-Finance-Education [2011]431) and the Natural Science Foundation of Guangdong Province (No. S2011010001556) for financial support.
文摘A series of new chiral 2(5H)-furanone derivatives containing bis-l,2,3-triazole moiety were designed and syn- thesized from (5S)-5-alkoxy-3,4-dihalo-2(5H)-furanones 1, dicarboxyl amino acids 2, propargyl bromide, and or- ganic azides 5 under mild conditions via the sequential three steps, including asymmetric Michael addi- tion-elimination, substitution and no-ligand click reaction. Twelve new intermediates, including N-[5-alkoxy- 2(5H)-furanonyl] dicarboxyl amino acids 3 and their corresponding propargyl esters 4, and twelve target molecules 6 were characterized by FTIR, 1H NMR, 13C NMR, MS and elemental analysis. The influences of different syn- thetic conditions and substrates in each step were investigated. The research provides a new method and idea for the synthesis of 2(5H)-furanone compounds with polyheterocyclic structure due to the diversities of four basic unit molecules.
文摘Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses.
基金Zhejiang Key Innovation Team of Green Pharmaceutical Technology (Project No.:2012R20043-12)
文摘A novel route for the synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2,ones from acetylated 2- aminothiazoles and 2-aminopyridines under Vilsmeier conditions has been developed. The plausible mechanism has also been proposed.