In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations we...In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations were used to study the thermal reactions of pyrene,1-methylpyrene,7,8,9,10-tetrahydrobenzopyrene,and mixtures of pyrene with 1-octene,cyclohexene,or styrene.The reactant conversion rates,reaction rates,and product distributions were calculated and compared,and the mechanisms were analyzed and discussed.The results demonstrated that methyl and naphthenic structures in aromatics might improve the conversion rates of reactants in hydrogen transfer processes,but their steric hindrances prohibited the generation of high polymers.The naphthenic structures could generate more free radicals and presented a more obvious inhibition effect on the condensation of polymers compared with the methyl side chains.It was discovered that when different olefins were mixed with pyrene,1-octene primarily underwent pyrolysis reactions,whereas cyclohexene mainly underwent hydrogen transfer reactions with pyrene and styrene,mostly producing superconjugated biradicals through condensation reactions with pyrene.In the mixture systems,the olefins scattered aromatic molecules,hindering the formation of pyrene trimers and higher polymers.According to the reactive molecular dynamics simulations,styrene may enhance the yield of dimer and enable the controlled polycondensation of pyrene.展开更多
As a kind of low-cost and readily available industrial byproduct, ethylene tar (ET) was for the first time utilized for the preparation of heat-resistant condensed polynuclear aromatic resin (COPNAR). The basic pr...As a kind of low-cost and readily available industrial byproduct, ethylene tar (ET) was for the first time utilized for the preparation of heat-resistant condensed polynuclear aromatic resin (COPNAR). The basic properties of ET and the resulted COPNAR were characterized by FT-IR, IH-NMR, TGA and elemental analysis. The test results showed that ET with high aromatic content (〉50%) was suitable for the synthesis of COPNAR with superior heat resistance. The average molecular structure of ET was obtained by means of the improved Brown-Ladner method, and the reaction mechanism was considered as an acid-catalyzed positive ion-typed polymerization. Our findings have provided a new route to develop ET into technology-added heat-resistant resins.展开更多
In order to improve the thermal stability of condensed polynuclear aromatic(COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by p...In order to improve the thermal stability of condensed polynuclear aromatic(COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by proton nuclear magnetic resonance spectrometry, solid carbon-13 nuclear magnetic resonance spectrometry and Fourier transform infrared spectroscopy. Microstructures of the uncured and the cured COPNA resins were studied by scanning electron microscopy and X-ray diffractometry. The thermal stability of COPNA resins before and after curing was tested by thermogravimetric analysis. The element composition of the cured COPNA resin heated at different temperatures was analyzed by an element analyzer. The results showed that the uncured COPNA resin reacted with the cross-linking agent during the curing process, and the curing mechanism was confirmed to be the electrophilic substitution reaction. Compared with the uncured COPNA resin, the cured COPNA resin had a smooth surface, well-ordered and streamlined sheet structure with more crystalline solids, better molecular arrangement and orientation. The weight loss process of the uncured and cured COPNA resins was divided into three stages. Carbon residue of the cured COPNA resin was 41.65% at 600 ℃, which was much higher than 25.02% of the uncured COPNA resin, which indicated that the cured COPNA resin had higher thermal stability.展开更多
Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,ther...Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.展开更多
The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione, bartbituric acid and 2-thiobarbituric acid proceede...The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione, bartbituric acid and 2-thiobarbituric acid proceeded very efficiently in water in the presence of triethylbenzylammonium chloride (TEBA) and the products were isolated simply by filtration.展开更多
The title compounds 3 and 4 condensed with aromatic aldehydes to give a--aroylsicinnamoyl ketene cyclic dithioacetals 5 and 6 with sodium ethoxide as the base. The stereochemistryofs and 6 was assigned as E-configurat...The title compounds 3 and 4 condensed with aromatic aldehydes to give a--aroylsicinnamoyl ketene cyclic dithioacetals 5 and 6 with sodium ethoxide as the base. The stereochemistryofs and 6 was assigned as E-configuration by 1H NMR.展开更多
The aldol condensation reactions of acetylferrocene with several aromatic aldehydes have been studied in the solid state.The results showed that they revealed different reactivities in the solid slate from that in sol...The aldol condensation reactions of acetylferrocene with several aromatic aldehydes have been studied in the solid state.The results showed that they revealed different reactivities in the solid slate from that in solution and eight compounds have been prepared. Their structures have been characterized by UV,IR,1~HNMR,HS and elemental analysis.展开更多
The ccndensation reactions occurred when heating bis(perfluoroalkane- sulfonyl)methanes with aromatic aldehydes in acetic acid anhydride and gave high yields of 1-aryl-2,2-di(perfluoroalkanesulfonyl)ethylenes The perf...The ccndensation reactions occurred when heating bis(perfluoroalkane- sulfonyl)methanes with aromatic aldehydes in acetic acid anhydride and gave high yields of 1-aryl-2,2-di(perfluoroalkanesulfonyl)ethylenes The perfluoroalkanesulfonyl groups R_FSO_2 are known as the strongest electron-attracting substituents^(1-2).This property is often used in the activation of C-C multiple and 2,2'-C-H bonds.The synthesis and reactions of perfluoroalkanesulfonyl substituted alkenes and alkynes are of great interest in synthetic organic chemistry^(3-6). Recently,Hanack^7 reported the preparation of 2-aryl-l-(perfluoroalkane- sulfonyl)acrylonitrile R_FSO_2C(CN)=CHAr.However,he failed to obtain the 1,1-di(perfluoroalkanesulfonyl)alkenes by the Knoevenagel reaction of bis(perfluoroalkanesulfonyl)methane with aldehydes.展开更多
The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
Condensates and light oils are generally characterized by high maturity, low concentration of sterane and terpane biomarkers and low content of non-hydrocarbon fraction. As a result, some commonly-used sterane, terpan...Condensates and light oils are generally characterized by high maturity, low concentration of sterane and terpane biomarkers and low content of non-hydrocarbon fraction. As a result, some commonly-used sterane, terpane and carbazole migration parameters in conventional oil reservoirs may have a certain limitation in condensate and light oil reservoirs for their poor signal-noise ratios in the gas chromatography-mass spectrometry (GC-MS). Naphthalene, phenanthrene and their methylated substituents, however, are present in significant concentrations in condensates and light oils. Taking the Fushan depression (in the Beibuwan Basin, Northern South China Sea) as an example, this paper attempts for the first time to use polycyclic aromatic hydrocarbon (PAH)-related parameters to trace migration directions and filling pathways for condensate and light oil reservoirs. The result shows that TMNr (i.e. 1, 3, 7-TMN/(1, 3, 7-TMN + 1, 2, 5-TMN), TMN: trimethylnaphthalene)), MPI-1 (i.e. 1.5×(2-MP + 3-MP)/(P + 1-MP + 9-MP), P: phenanthrene MP: methyiphenanthrene), MN/DMN (∑methylnaphthalene/∑dimethylnaphthalene, %) and MN/TMN (∑nethylnaphthalene/∑trimethylna- phthalene, %) can be used to trace the filling pathways of condensate and light oil reservoirs. These parameters, together with geological consideration and other bulk oil properties (e.g. the gas to oil ratio and density), suggest that the condensates and light oils in the Huachang oil and gas field are mainly sourced from the Bailian sag that is located to the northeast of the Huachang uplift in the Fushan depression.展开更多
The Sanchi oil tanker collision in the East China Sea on January 6th, 2018 has caused worldwide attention due to its uniqueness. A considerable amount of highly volatile natural-gas condensate oil was spilled, burned ...The Sanchi oil tanker collision in the East China Sea on January 6th, 2018 has caused worldwide attention due to its uniqueness. A considerable amount of highly volatile natural-gas condensate oil was spilled, burned and sank with the Sanchi tanker, this entirely new kind of maritime disaster has posed massive unknowns to the public. In this study, for better understanding of the evaporative behavior of condensate oils, two condensate oils were investigated under various laboratory conditions. The overall result demonstrates that the evaporation of condensate oils is highly dependent on the air-exposed time and the total loss of condensate oils could be more than 90% within a short time. However, a certain amount of the high-molecular weight and toxic oil contents such as phenanthrenes still highly remain in the aquatic system even after a long evaporation process, indicating their detrimental potentials to the aquatic organisms. Based on these data, for the Sanchi oil spill accident, it is assumed that although the evaporation weathering of the total condensate oil mass is probably tremendous, the long-term ecological risks of the remaining oil components in the marine environment are strongly recommended to be carefully evaluated.展开更多
A protocol for the Knoevenagel condensation of aromatic aldehydes with methylene compounds catalyzed by task specifed ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium lactate under solvent-free conditions has bee...A protocol for the Knoevenagel condensation of aromatic aldehydes with methylene compounds catalyzed by task specifed ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium lactate under solvent-free conditions has been developed. The reactions proceed at ambient temperature and the work-up procedures are very simple. Good to excellent yields could be obtained. The ionic liuid could be simply prepared and recycled efficiently.展开更多
Under microwave irradiation, the one-pot multicomponent condensation reaction of three moles of aromatic aldehydes with two moles of cyclic ketones having free a,a'-methylene positions such as cyclopentanone or cyclo...Under microwave irradiation, the one-pot multicomponent condensation reaction of three moles of aromatic aldehydes with two moles of cyclic ketones having free a,a'-methylene positions such as cyclopentanone or cyclohexanone in the presence of ammonium acetate and acetic acid afforded dicycloalkenopyridines with two a-arylidene groups in high yields. Under the similar reaction condition, the reaction of aromatic aldehydes with 1-tetralone having only one a-methylene position alternatively resulted in 10-aryl-2,3:5,6-dibenzoacridines.展开更多
Acenapththylene-imide(An I),similar to naphthalene diimide(NDI),is an outstanding building block for organic functional materials and has gained a lot of research attention.Herein,Sulphur and Selenium-embedded AnI-con...Acenapththylene-imide(An I),similar to naphthalene diimide(NDI),is an outstanding building block for organic functional materials and has gained a lot of research attention.Herein,Sulphur and Selenium-embedded AnI-containing polycyclic aromatic hydrocarbon molecules,AnI-SQ and AnI-SeQ,with[1,2,5]thiadiazolo[3,4-g]quinoxaline(SQ)and[1,2,5]selenadiazolo[3,4-g]quinoxaline(Se Q)are designed and synthesized with low-lying LUMO energy levels.The absorption and emission of AnI-SQ and An I-Se Q displayed a bathochromic shift upon protonation of the C=N bond.Besides,theoretical calculation indicates remarkable rigid planar backbones for both An I-SQ and An I-Se Q.Through self-assembly with polymeric Pluronic?F-127,corresponding hydrophilic nanoparticles(NPs)were prepared with low cytotoxicity.And AnI-SQ NPs could be applied for in vitro two-photon fluorescence imaging.展开更多
The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, firs...The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, first Herndon number, etc. It is shown that this polynomial can be used for calculating the resonance energy of condensed aromatic hydrocarbons with better accuracy.展开更多
基金financially supported by the National Natural Science Foundation of China(Approval No.42172168).
文摘In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations were used to study the thermal reactions of pyrene,1-methylpyrene,7,8,9,10-tetrahydrobenzopyrene,and mixtures of pyrene with 1-octene,cyclohexene,or styrene.The reactant conversion rates,reaction rates,and product distributions were calculated and compared,and the mechanisms were analyzed and discussed.The results demonstrated that methyl and naphthenic structures in aromatics might improve the conversion rates of reactants in hydrogen transfer processes,but their steric hindrances prohibited the generation of high polymers.The naphthenic structures could generate more free radicals and presented a more obvious inhibition effect on the condensation of polymers compared with the methyl side chains.It was discovered that when different olefins were mixed with pyrene,1-octene primarily underwent pyrolysis reactions,whereas cyclohexene mainly underwent hydrogen transfer reactions with pyrene and styrene,mostly producing superconjugated biradicals through condensation reactions with pyrene.In the mixture systems,the olefins scattered aromatic molecules,hindering the formation of pyrene trimers and higher polymers.According to the reactive molecular dynamics simulations,styrene may enhance the yield of dimer and enable the controlled polycondensation of pyrene.
基金supported by the Program for New Century Excellent Talents in University, China Ministry of Education, 2009 (No. NCET-10-0768)the National Natural Science Foundation of China (Nos. 20876176 and 51172285)the Natural Science Foundation of Shandong Province (ZR2011EL031, ZR2011EL030)
文摘As a kind of low-cost and readily available industrial byproduct, ethylene tar (ET) was for the first time utilized for the preparation of heat-resistant condensed polynuclear aromatic resin (COPNAR). The basic properties of ET and the resulted COPNAR were characterized by FT-IR, IH-NMR, TGA and elemental analysis. The test results showed that ET with high aromatic content (〉50%) was suitable for the synthesis of COPNAR with superior heat resistance. The average molecular structure of ET was obtained by means of the improved Brown-Ladner method, and the reaction mechanism was considered as an acid-catalyzed positive ion-typed polymerization. Our findings have provided a new route to develop ET into technology-added heat-resistant resins.
基金supported by the National Natural Science Foundation of China(51172285 and 51372277)the Fundamental Research Funds for the Central Universities(14CX02060A,15CX02084A)the Natural Science Foundation of Shandong Province(ZR2011EL030)
文摘In order to improve the thermal stability of condensed polynuclear aromatic(COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by proton nuclear magnetic resonance spectrometry, solid carbon-13 nuclear magnetic resonance spectrometry and Fourier transform infrared spectroscopy. Microstructures of the uncured and the cured COPNA resins were studied by scanning electron microscopy and X-ray diffractometry. The thermal stability of COPNA resins before and after curing was tested by thermogravimetric analysis. The element composition of the cured COPNA resin heated at different temperatures was analyzed by an element analyzer. The results showed that the uncured COPNA resin reacted with the cross-linking agent during the curing process, and the curing mechanism was confirmed to be the electrophilic substitution reaction. Compared with the uncured COPNA resin, the cured COPNA resin had a smooth surface, well-ordered and streamlined sheet structure with more crystalline solids, better molecular arrangement and orientation. The weight loss process of the uncured and cured COPNA resins was divided into three stages. Carbon residue of the cured COPNA resin was 41.65% at 600 ℃, which was much higher than 25.02% of the uncured COPNA resin, which indicated that the cured COPNA resin had higher thermal stability.
基金supported by the National Natural Science Foundation of China(Nos.42177354 and 42020104001)the National Key R&D Program of China(No.2019YFC0214402)+1 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)Guangdong Basic and Applied Basic Research Foundation(No.2019B151502064).
文摘Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.
文摘The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione, bartbituric acid and 2-thiobarbituric acid proceeded very efficiently in water in the presence of triethylbenzylammonium chloride (TEBA) and the products were isolated simply by filtration.
文摘The title compounds 3 and 4 condensed with aromatic aldehydes to give a--aroylsicinnamoyl ketene cyclic dithioacetals 5 and 6 with sodium ethoxide as the base. The stereochemistryofs and 6 was assigned as E-configuration by 1H NMR.
文摘The aldol condensation reactions of acetylferrocene with several aromatic aldehydes have been studied in the solid state.The results showed that they revealed different reactivities in the solid slate from that in solution and eight compounds have been prepared. Their structures have been characterized by UV,IR,1~HNMR,HS and elemental analysis.
文摘The ccndensation reactions occurred when heating bis(perfluoroalkane- sulfonyl)methanes with aromatic aldehydes in acetic acid anhydride and gave high yields of 1-aryl-2,2-di(perfluoroalkanesulfonyl)ethylenes The perfluoroalkanesulfonyl groups R_FSO_2 are known as the strongest electron-attracting substituents^(1-2).This property is often used in the activation of C-C multiple and 2,2'-C-H bonds.The synthesis and reactions of perfluoroalkanesulfonyl substituted alkenes and alkynes are of great interest in synthetic organic chemistry^(3-6). Recently,Hanack^7 reported the preparation of 2-aryl-l-(perfluoroalkane- sulfonyl)acrylonitrile R_FSO_2C(CN)=CHAr.However,he failed to obtain the 1,1-di(perfluoroalkanesulfonyl)alkenes by the Knoevenagel reaction of bis(perfluoroalkanesulfonyl)methane with aldehydes.
文摘The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
基金supported by the Natural Science Foundation of China(Grant No.40972089),CNPC Innovation Fund(Grant No.07E1001)the State Key Laboratory of the Petroleum Resources and Prospecting(Grant No.PRPDX2008-01)
文摘Condensates and light oils are generally characterized by high maturity, low concentration of sterane and terpane biomarkers and low content of non-hydrocarbon fraction. As a result, some commonly-used sterane, terpane and carbazole migration parameters in conventional oil reservoirs may have a certain limitation in condensate and light oil reservoirs for their poor signal-noise ratios in the gas chromatography-mass spectrometry (GC-MS). Naphthalene, phenanthrene and their methylated substituents, however, are present in significant concentrations in condensates and light oils. Taking the Fushan depression (in the Beibuwan Basin, Northern South China Sea) as an example, this paper attempts for the first time to use polycyclic aromatic hydrocarbon (PAH)-related parameters to trace migration directions and filling pathways for condensate and light oil reservoirs. The result shows that TMNr (i.e. 1, 3, 7-TMN/(1, 3, 7-TMN + 1, 2, 5-TMN), TMN: trimethylnaphthalene)), MPI-1 (i.e. 1.5×(2-MP + 3-MP)/(P + 1-MP + 9-MP), P: phenanthrene MP: methyiphenanthrene), MN/DMN (∑methylnaphthalene/∑dimethylnaphthalene, %) and MN/TMN (∑nethylnaphthalene/∑trimethylna- phthalene, %) can be used to trace the filling pathways of condensate and light oil reservoirs. These parameters, together with geological consideration and other bulk oil properties (e.g. the gas to oil ratio and density), suggest that the condensates and light oils in the Huachang oil and gas field are mainly sourced from the Bailian sag that is located to the northeast of the Huachang uplift in the Fushan depression.
基金partly supported by the National Natural Science Foundation of China (No.41807341)the Young Orient Scholars Program of Shanghai (No.QD2017038)+1 种基金the Doctoral Scientific Research Starting Foundation of Shanghai Ocean UniversityShanghai Special Research Fund for Training College's Young Teachers (No.ZZSHOU18025)。
文摘The Sanchi oil tanker collision in the East China Sea on January 6th, 2018 has caused worldwide attention due to its uniqueness. A considerable amount of highly volatile natural-gas condensate oil was spilled, burned and sank with the Sanchi tanker, this entirely new kind of maritime disaster has posed massive unknowns to the public. In this study, for better understanding of the evaporative behavior of condensate oils, two condensate oils were investigated under various laboratory conditions. The overall result demonstrates that the evaporation of condensate oils is highly dependent on the air-exposed time and the total loss of condensate oils could be more than 90% within a short time. However, a certain amount of the high-molecular weight and toxic oil contents such as phenanthrenes still highly remain in the aquatic system even after a long evaporation process, indicating their detrimental potentials to the aquatic organisms. Based on these data, for the Sanchi oil spill accident, it is assumed that although the evaporation weathering of the total condensate oil mass is probably tremendous, the long-term ecological risks of the remaining oil components in the marine environment are strongly recommended to be carefully evaluated.
基金Supported by the National Natural Science Foundation of China(No.20776127)the National Key Technology Research and Development Program of China(No.2007BAI34B07)
文摘A protocol for the Knoevenagel condensation of aromatic aldehydes with methylene compounds catalyzed by task specifed ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium lactate under solvent-free conditions has been developed. The reactions proceed at ambient temperature and the work-up procedures are very simple. Good to excellent yields could be obtained. The ionic liuid could be simply prepared and recycled efficiently.
基金Supported by the National Natural Science Foundation of China(No.20672091)
文摘Under microwave irradiation, the one-pot multicomponent condensation reaction of three moles of aromatic aldehydes with two moles of cyclic ketones having free a,a'-methylene positions such as cyclopentanone or cyclohexanone in the presence of ammonium acetate and acetic acid afforded dicycloalkenopyridines with two a-arylidene groups in high yields. Under the similar reaction condition, the reaction of aromatic aldehydes with 1-tetralone having only one a-methylene position alternatively resulted in 10-aryl-2,3:5,6-dibenzoacridines.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK20200092)the National Natural Science Foundation of China(No.21972067)。
文摘Acenapththylene-imide(An I),similar to naphthalene diimide(NDI),is an outstanding building block for organic functional materials and has gained a lot of research attention.Herein,Sulphur and Selenium-embedded AnI-containing polycyclic aromatic hydrocarbon molecules,AnI-SQ and AnI-SeQ,with[1,2,5]thiadiazolo[3,4-g]quinoxaline(SQ)and[1,2,5]selenadiazolo[3,4-g]quinoxaline(Se Q)are designed and synthesized with low-lying LUMO energy levels.The absorption and emission of AnI-SQ and An I-Se Q displayed a bathochromic shift upon protonation of the C=N bond.Besides,theoretical calculation indicates remarkable rigid planar backbones for both An I-SQ and An I-Se Q.Through self-assembly with polymeric Pluronic?F-127,corresponding hydrophilic nanoparticles(NPs)were prepared with low cytotoxicity.And AnI-SQ NPs could be applied for in vitro two-photon fluorescence imaging.
基金Project supported by the National Natural Science Foundation of China.
文摘The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, first Herndon number, etc. It is shown that this polynomial can be used for calculating the resonance energy of condensed aromatic hydrocarbons with better accuracy.