Keto esters 8, 4-arylcarbonyl-3-methoxycarbonyl-2-phenylfurans, potential precursors of the synthesis of furofuran lignans, were obtained from dimethyl 2-phenylfuran-3,4-dicarboxylate 2. Diester 2 was selectively hydr...Keto esters 8, 4-arylcarbonyl-3-methoxycarbonyl-2-phenylfurans, potential precursors of the synthesis of furofuran lignans, were obtained from dimethyl 2-phenylfuran-3,4-dicarboxylate 2. Diester 2 was selectively hydrolyzed to monoacid 6 followed by converting to its acid chloride 7. Friedel-Crafts acylation reactions of 7 with aromatic compounds afforded keto esters 8. The geometric structures of 8 and its precursors were elucidated and verified by NMR spectra.展开更多
2-Phenylfuran-3,4-dicarboxylic acid anhydride reacted with seven aromatic compounds, of which five gave keto acids in yields of 94%-63%. The structure of the keto acid was elucidated by reducing it to hydroxy acid and...2-Phenylfuran-3,4-dicarboxylic acid anhydride reacted with seven aromatic compounds, of which five gave keto acids in yields of 94%-63%. The structure of the keto acid was elucidated by reducing it to hydroxy acid and analyzing with NMR technique.展开更多
Silica gel supported aluminium trichloride（SiO2-AlCl3） has been shown to be a mild,efficient,and chemoseiective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides.The catal...Silica gel supported aluminium trichloride（SiO2-AlCl3） has been shown to be a mild,efficient,and chemoseiective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides.The catalyst can be reused up to five times after simple washing with ether and is stable（as a bench top catalyst）.展开更多
Zeolite catalyzed Friedel-Crafts reactions were examined using acetic anhydride as an acetylating agent and an acetic acid as a solvent. It revealed that the reaction of anisole smoothly occurred quantitatively for 3 ...Zeolite catalyzed Friedel-Crafts reactions were examined using acetic anhydride as an acetylating agent and an acetic acid as a solvent. It revealed that the reaction of anisole smoothly occurred quantitatively for 3 h using mordenite zeolite with SiO2/Al2O3 = 200, and with SiO2/Al2O3 = 110, the increasing of Br?nsted acidity allowed to completely react within 2 h. Furthermore the selectivity of 4-methoxyacetophenone (4-MA) among the isomers was found to be quantitative, no by-products and/or isomers were not detectable. With the excellent recyclability and reusability, the mordenite zeolite exhibited at least 30 times quantitatively both conversion of anisole and selectivity of 4-MA. The mordenite catalysts of fresh and the used after 30 times were characterized. This opportunity obviously indicates the sufficient shape selective catalyst of mordenite zeolite and gives a green synthetic tool for heterogeneous acylation reaction.展开更多
The effect of microwave irradiation on the intermolecular and intramolecular Friedel-Crafts acylation of aromatic compounds was investigated. Microwave irradiation had no effect on the intermolecular reaction but had ...The effect of microwave irradiation on the intermolecular and intramolecular Friedel-Crafts acylation of aromatic compounds was investigated. Microwave irradiation had no effect on the intermolecular reaction but had an accelerating effect on the intramolecular reaction. This enhanced intramolecular reactivity that was attributed to the high probability of close proximity between the reaction sites.展开更多
Metal-organic framework MIL-53(Al) was synthesized by a solvothermal method using aluminum nitrate as the aluminium source and 1,4-benzenedicarboxylic acid(H2BDC) as the organic ligand. The structure of samples was ch...Metal-organic framework MIL-53(Al) was synthesized by a solvothermal method using aluminum nitrate as the aluminium source and 1,4-benzenedicarboxylic acid(H2BDC) as the organic ligand. The structure of samples was characterized by X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR). The catalytic activity and recyclability of MIL-53(Al) catalyst for the Friedel-Crafts acylation reaction of indole with benzoyl chloride were evaluated. The reaction conditions were optimized and a reaction mechanism was suggested. The results showed that the MIL-53(Al) catalyst exhibited good catalytic activity and recyclability for the Friedel-Crafts acylation reaction. When the molar ratio of indole and MIL-53(Al) catalyst was 1:0.06(n1:ncatalyst), the molar ratio of indole and benzoyl chloride was 1:3, and the solvent was dichloromethane, the conversion of indole could reach 97.1% and the selectivity of 3-acylindole could reach 81.1% at 25 °C after 8 h. The catalyst can be reused without significant degradation in catalytic activity. After the catalyst was reused five times, the conversion of indole was 87.6% and the selectivity of 3-acylindole was 79.5%.展开更多
Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce ...Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce their prospects as industrial catalyst.Herein, a novel hybrid material HPW@Zr-BTC,composed of 12-tungstophoric acid(HPW) and Zr^(Ⅳ)-benzene tri-carboxylate(Zr-BTC) metal-organic framework(MOF), was prepared via one-pot solvothermal method. Excellent HPW loading up to 32.3 wt% was achieved, and HPW@Zr-BTC composite proved to be highly stable, besides the crystalline morphology of Zr-BTC was intact. The catalytic activity of the hybrid composite was explored via Friedel-Crafts acylation of anisole with benzoyl chloride.The 28.2 wt% HPW@Zr-BTC showed excellent catalytic performance, with 99.4% anisole conversion and 97.6% yield(pmethoxybenzophenone) under solvent free conditions. Excellent retention of catalytic activity was achieved after at least five consecutive runs due to non-observable HPW leaching. The promising activity and stability of the catalyst forecasted its potential industrial applications.展开更多
文摘Keto esters 8, 4-arylcarbonyl-3-methoxycarbonyl-2-phenylfurans, potential precursors of the synthesis of furofuran lignans, were obtained from dimethyl 2-phenylfuran-3,4-dicarboxylate 2. Diester 2 was selectively hydrolyzed to monoacid 6 followed by converting to its acid chloride 7. Friedel-Crafts acylation reactions of 7 with aromatic compounds afforded keto esters 8. The geometric structures of 8 and its precursors were elucidated and verified by NMR spectra.
文摘2-Phenylfuran-3,4-dicarboxylic acid anhydride reacted with seven aromatic compounds, of which five gave keto acids in yields of 94%-63%. The structure of the keto acid was elucidated by reducing it to hydroxy acid and analyzing with NMR technique.
文摘Silica gel supported aluminium trichloride（SiO2-AlCl3） has been shown to be a mild,efficient,and chemoseiective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides.The catalyst can be reused up to five times after simple washing with ether and is stable（as a bench top catalyst）.
文摘Zeolite catalyzed Friedel-Crafts reactions were examined using acetic anhydride as an acetylating agent and an acetic acid as a solvent. It revealed that the reaction of anisole smoothly occurred quantitatively for 3 h using mordenite zeolite with SiO2/Al2O3 = 200, and with SiO2/Al2O3 = 110, the increasing of Br?nsted acidity allowed to completely react within 2 h. Furthermore the selectivity of 4-methoxyacetophenone (4-MA) among the isomers was found to be quantitative, no by-products and/or isomers were not detectable. With the excellent recyclability and reusability, the mordenite zeolite exhibited at least 30 times quantitatively both conversion of anisole and selectivity of 4-MA. The mordenite catalysts of fresh and the used after 30 times were characterized. This opportunity obviously indicates the sufficient shape selective catalyst of mordenite zeolite and gives a green synthetic tool for heterogeneous acylation reaction.
文摘The effect of microwave irradiation on the intermolecular and intramolecular Friedel-Crafts acylation of aromatic compounds was investigated. Microwave irradiation had no effect on the intermolecular reaction but had an accelerating effect on the intramolecular reaction. This enhanced intramolecular reactivity that was attributed to the high probability of close proximity between the reaction sites.
基金supported by the National Natural Science Foundation of China(21136001,21173018)
文摘Metal-organic framework MIL-53(Al) was synthesized by a solvothermal method using aluminum nitrate as the aluminium source and 1,4-benzenedicarboxylic acid(H2BDC) as the organic ligand. The structure of samples was characterized by X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR). The catalytic activity and recyclability of MIL-53(Al) catalyst for the Friedel-Crafts acylation reaction of indole with benzoyl chloride were evaluated. The reaction conditions were optimized and a reaction mechanism was suggested. The results showed that the MIL-53(Al) catalyst exhibited good catalytic activity and recyclability for the Friedel-Crafts acylation reaction. When the molar ratio of indole and MIL-53(Al) catalyst was 1:0.06(n1:ncatalyst), the molar ratio of indole and benzoyl chloride was 1:3, and the solvent was dichloromethane, the conversion of indole could reach 97.1% and the selectivity of 3-acylindole could reach 81.1% at 25 °C after 8 h. The catalyst can be reused without significant degradation in catalytic activity. After the catalyst was reused five times, the conversion of indole was 87.6% and the selectivity of 3-acylindole was 79.5%.
基金supported by the National Key Research and Development Program of China(2016YFB0601303)the National Natural Science Foundation of China(51374193,21676278)+1 种基金Key Program of National Natural Science Foundation of China(9143420)Chinese Academy of Sciences,State Administration of Foreign Experts Affairs(CAS/SAFEA)International Partnership Program for Creative Research Teams(20140491518)
文摘Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce their prospects as industrial catalyst.Herein, a novel hybrid material HPW@Zr-BTC,composed of 12-tungstophoric acid(HPW) and Zr^(Ⅳ)-benzene tri-carboxylate(Zr-BTC) metal-organic framework(MOF), was prepared via one-pot solvothermal method. Excellent HPW loading up to 32.3 wt% was achieved, and HPW@Zr-BTC composite proved to be highly stable, besides the crystalline morphology of Zr-BTC was intact. The catalytic activity of the hybrid composite was explored via Friedel-Crafts acylation of anisole with benzoyl chloride.The 28.2 wt% HPW@Zr-BTC showed excellent catalytic performance, with 99.4% anisole conversion and 97.6% yield(pmethoxybenzophenone) under solvent free conditions. Excellent retention of catalytic activity was achieved after at least five consecutive runs due to non-observable HPW leaching. The promising activity and stability of the catalyst forecasted its potential industrial applications.
