A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the ...A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeC13/SiO2. These catalysts were characterized by BET, NH3-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeC13/SiO2 has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeC13/SiO2 ex- hibited higher molar ratio of Lewis acid sites and Brtpnsted acid sites, which might be another reason for the in- crease of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2% conversion and 82.0% selectivity were obtained. Mean- while, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.展开更多
A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL...A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL@PD-MNPs） with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significant- ly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy, A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin （DMY） in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation.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
A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3...A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3,4,7,8,11) featuring different chain length as acyl donors and alkaline protease from Bacillus subtilis as catalyst,troxerutin was regioselective acylated at B ethoxyl group.The results indicated that the regioselectivity of the enzyme-catalyzed acylation was not affected by the chain length o...展开更多
A novel catalytic system, ZnCl2 supported on alumina, was found to be an efficient and readily available medium for the solvent-free Friedel-Crafts acylation reactions under microwave irradiation. Good yields and high...A novel catalytic system, ZnCl2 supported on alumina, was found to be an efficient and readily available medium for the solvent-free Friedel-Crafts acylation reactions under microwave irradiation. Good yields and high catalytic efficiencies were observed within short reaction times. Comparing with silica gel, alumina was more efficient under the same conditions.展开更多
The regioselective acylation of quercetin catalyzed by a novel thermophilic esterase（APE1547） from the archaeon Aeropyrum pernix K1 was successfully conducted in organic solvents.The effects of acyl donor,substrate ...The regioselective acylation of quercetin catalyzed by a novel thermophilic esterase（APE1547） from the archaeon Aeropyrum pernix K1 was successfully conducted in organic solvents.The effects of acyl donor,substrate ratio,organic solvent,temperature,and water activity were investigated.Under the optimum conditions,a yield of 74% for its mono ester could be achieved in the reaction for about 6 h.With the reaction time extending to about 30 h,the final conversion of quercetin was about 100% and three products were synthesized.展开更多
Methoxyacetophenone(4 MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite. The addition of an appropriate amount of some solvent such as dichloromethane, chloroform, c...Methoxyacetophenone(4 MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite. The addition of an appropriate amount of some solvent such as dichloromethane, chloroform, carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent. HY zeolite used can be recovered, and reused after being regenerated, obtaining almost the same yield of 4 MAP as the fresh zeolite.展开更多
Solid superacid, silica-supported polytrifluoromethanesulfosiloxane (SiO2-Si-SCF3) wasfirstly used in the Friedel-Crafts acylation of ferrocene as a novel catalyst. IR spectra, WAXD andspecific surface area of the sup...Solid superacid, silica-supported polytrifluoromethanesulfosiloxane (SiO2-Si-SCF3) wasfirstly used in the Friedel-Crafts acylation of ferrocene as a novel catalyst. IR spectra, WAXD andspecific surface area of the superacid SiO2-Si-SCF3 were also investigated.展开更多
A series of aromatic ketones 4-acyl anisole were synthesized with high yield by using carboxylic acids as acylating agents and a HY zeolite as catalyst.
A series of acyls （Ac, Bz and Ts） were introduced regioselectively to the 2-hydroxyl in methyl and ally 3-O-benzyl-α-L-rhamnopyranosides mediated by silver（I） oxide in the presence of a catalytic amount of potass...A series of acyls （Ac, Bz and Ts） were introduced regioselectively to the 2-hydroxyl in methyl and ally 3-O-benzyl-α-L-rhamnopyranosides mediated by silver（I） oxide in the presence of a catalytic amount of potassium iodide in 56-78% yields.展开更多
Acylation of 2-methylnaphthalene(2-MN) is a very important reaction in organic synthesis,and the effiency of the continuous reactor is more than one of the batch reactor.Considering that the Friedel–Crafts acylation ...Acylation of 2-methylnaphthalene(2-MN) is a very important reaction in organic synthesis,and the effiency of the continuous reactor is more than one of the batch reactor.Considering that the Friedel–Crafts acylation is a rapid exothermic reaction,in this study,we perform the acylation of 2-MN in a stainless steel microchannel flow reactor,which is characterized by high mass and heat transfer rates.The effect of reactant ratio,mixing temperature,reaction temperature,and reaction time on product yield and selectivity were investigated.Under the optimal conditions,2-methyl-6-propionylnaphthalene(2,6-MPN) was obtained in 85.8% yield with 87.5% selectivity.Compared with the conventional batch system,the continuous flow microchannel reactor provides a more efficient method for the synthesis of 2,6-MPN.展开更多
10β-OH can be acylated cleanly when 7α-OH is also free, and thus a facile access to semisynthesis of 7-epi-paclitaxel was proposed. A 2's, 3's-oxazoline paclitaxel analog was serendipitously synthesized
The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-a...The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-acyl to N-acyl product depends upon the acylation reagents. O-acyl derivatives can be converted to the N-acyl compounds by isomerization under acidic conditions or heating.展开更多
Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer mate...Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1↑HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows： the molar fraction of AlCl3 in ionic liquid [x（AlCl3）] being 0.67, molar ratio of ionic liquid to anthracene being 2：1, molar ratio of oxalyl chloride to anthracene being 2：1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.展开更多
An acylation method of 3,4-diaminofurazan was developed. Under the catalysts of p-Tolu- enesulfonic acid, 3-amino-4-formylaminofurazan, 3-amino-4-acetylaminofurazan, 3-amino-4-propio- nylaminofurazan, 3-amino-4-butylr...An acylation method of 3,4-diaminofurazan was developed. Under the catalysts of p-Tolu- enesulfonic acid, 3-amino-4-formylaminofurazan, 3-amino-4-acetylaminofurazan, 3-amino-4-propio- nylaminofurazan, 3-amino-4-butylramino-furazan and 3-amino-4-benzoylaminofurazan were synthe- sized by acylation of 3,4-diaminofurazan with formic acid, acetic acid, propionic acid, butyric acid and benzoic acid respectively. Also, 3,4-diacetylaminofurazan and 3,4-dipropionylaminofurazan were synthesized by acylation of 3,4-diaminofurazan with acetic anhydride and propionic anhydride re- spectively. Compared with the traditional method which uses acyl halogen as reagent, our method reduced the reaction time and increased the yield and purify. The 3-amino-4-acylaminofurazan could be hydrolyzed to 3,4-diaminofurazan in ethanol with acid catalyst.展开更多
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
基金Supported by the National Basic Research Program of China("973"Program,No.21476163)
文摘A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeC13/SiO2. These catalysts were characterized by BET, NH3-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeC13/SiO2 has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeC13/SiO2 ex- hibited higher molar ratio of Lewis acid sites and Brtpnsted acid sites, which might be another reason for the in- crease of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2% conversion and 82.0% selectivity were obtained. Mean- while, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.
基金supported by the National Natural Science Foundation of China(21336002,21222606,21376096)the Key Program of Guangdong Natural Science Foundation(S2013020013049)+1 种基金the Fundamental Research Funds for the Chinese Universities(2015PT002,2015ZP009)the Program of State Key Laboratory of Pulp and Paper Engineering(2015C04)~~
文摘A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL@PD-MNPs） with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significant- ly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy, A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin （DMY） in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation.
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）.
基金the Science and Technology hall of Henan Province(No.072300420070No.82102330014)China,for financially supported to this work.
文摘A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3,4,7,8,11) featuring different chain length as acyl donors and alkaline protease from Bacillus subtilis as catalyst,troxerutin was regioselective acylated at B ethoxyl group.The results indicated that the regioselectivity of the enzyme-catalyzed acylation was not affected by the chain length o...
文摘A novel catalytic system, ZnCl2 supported on alumina, was found to be an efficient and readily available medium for the solvent-free Friedel-Crafts acylation reactions under microwave irradiation. Good yields and high catalytic efficiencies were observed within short reaction times. Comparing with silica gel, alumina was more efficient under the same conditions.
基金Supported by the National Natural Science Foundation of China(Nos.31070708,21172093 and 20772046)the Natural Science Foundation of Jilin Province,China(No.201115038)
文摘The regioselective acylation of quercetin catalyzed by a novel thermophilic esterase（APE1547） from the archaeon Aeropyrum pernix K1 was successfully conducted in organic solvents.The effects of acyl donor,substrate ratio,organic solvent,temperature,and water activity were investigated.Under the optimum conditions,a yield of 74% for its mono ester could be achieved in the reaction for about 6 h.With the reaction time extending to about 30 h,the final conversion of quercetin was about 100% and three products were synthesized.
文摘Methoxyacetophenone(4 MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite. The addition of an appropriate amount of some solvent such as dichloromethane, chloroform, carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent. HY zeolite used can be recovered, and reused after being regenerated, obtaining almost the same yield of 4 MAP as the fresh zeolite.
基金We are grateful to the National Natural Science Foundation of China(20362007)for the financial support.
文摘Solid superacid, silica-supported polytrifluoromethanesulfosiloxane (SiO2-Si-SCF3) wasfirstly used in the Friedel-Crafts acylation of ferrocene as a novel catalyst. IR spectra, WAXD andspecific surface area of the superacid SiO2-Si-SCF3 were also investigated.
文摘A series of aromatic ketones 4-acyl anisole were synthesized with high yield by using carboxylic acids as acylating agents and a HY zeolite as catalyst.
基金financially supported by the National Natural Science Foundation of China(No.30300434)the 0utstanding Youth Foundation of Sichuan Province(No.04ZQ026-039).
文摘A series of acyls （Ac, Bz and Ts） were introduced regioselectively to the 2-hydroxyl in methyl and ally 3-O-benzyl-α-L-rhamnopyranosides mediated by silver（I） oxide in the presence of a catalytic amount of potassium iodide in 56-78% yields.
基金Supported by the National Natural Science Foundation of China(91634101)The Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality(IDHT20180508)
文摘Acylation of 2-methylnaphthalene(2-MN) is a very important reaction in organic synthesis,and the effiency of the continuous reactor is more than one of the batch reactor.Considering that the Friedel–Crafts acylation is a rapid exothermic reaction,in this study,we perform the acylation of 2-MN in a stainless steel microchannel flow reactor,which is characterized by high mass and heat transfer rates.The effect of reactant ratio,mixing temperature,reaction temperature,and reaction time on product yield and selectivity were investigated.Under the optimal conditions,2-methyl-6-propionylnaphthalene(2,6-MPN) was obtained in 85.8% yield with 87.5% selectivity.Compared with the conventional batch system,the continuous flow microchannel reactor provides a more efficient method for the synthesis of 2,6-MPN.
文摘10β-OH can be acylated cleanly when 7α-OH is also free, and thus a facile access to semisynthesis of 7-epi-paclitaxel was proposed. A 2's, 3's-oxazoline paclitaxel analog was serendipitously synthesized
基金Supposed by the National Natural Science Foundation of China
文摘The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-acyl to N-acyl product depends upon the acylation reagents. O-acyl derivatives can be converted to the N-acyl compounds by isomerization under acidic conditions or heating.
基金National Natural Science Foundation of China (No.20207003)
文摘Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1↑HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows： the molar fraction of AlCl3 in ionic liquid [x（AlCl3）] being 0.67, molar ratio of ionic liquid to anthracene being 2：1, molar ratio of oxalyl chloride to anthracene being 2：1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.
基金Project supported by National Natural Science Foundation of China（Grant No. 20472048）, and Science Foundation of Shang-hai Municipal Commission of Science and Technology（ Grant No. 03ZR14033）
文摘Acetanilide was synthesized from nitrobenzene in the presence of acetic anhydride, acetic acid and samarium by a one-pot procedure in good yield.
文摘An acylation method of 3,4-diaminofurazan was developed. Under the catalysts of p-Tolu- enesulfonic acid, 3-amino-4-formylaminofurazan, 3-amino-4-acetylaminofurazan, 3-amino-4-propio- nylaminofurazan, 3-amino-4-butylramino-furazan and 3-amino-4-benzoylaminofurazan were synthe- sized by acylation of 3,4-diaminofurazan with formic acid, acetic acid, propionic acid, butyric acid and benzoic acid respectively. Also, 3,4-diacetylaminofurazan and 3,4-dipropionylaminofurazan were synthesized by acylation of 3,4-diaminofurazan with acetic anhydride and propionic anhydride re- spectively. Compared with the traditional method which uses acyl halogen as reagent, our method reduced the reaction time and increased the yield and purify. The 3-amino-4-acylaminofurazan could be hydrolyzed to 3,4-diaminofurazan in ethanol with acid catalyst.
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.
