A novel supramolecular mixed ligand complex of formula [Cu(PTS)2(Him)2(H2O)2] (C20H26CuN4O8S2,PTS=p-toluenesulfonate,Him=imidazole) has been synthesized in aqueous solution and characterized by elemental analy...A novel supramolecular mixed ligand complex of formula [Cu(PTS)2(Him)2(H2O)2] (C20H26CuN4O8S2,PTS=p-toluenesulfonate,Him=imidazole) has been synthesized in aqueous solution and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The compound crystallizes in the monoclinic system,space group P21/n,Z=2,a=5.650(2),b=14.671(3),c=14.638(3),β=100.10(3)°,V=1194.60(4)3,Dc=1.607 g/cm3,μ(MoKα)=1.143 mm-1,F(000)=598,R=0.0615 and wR=0.1503 for 1752 observed reflections with I 〉 2σ(I).The copper(II) ion in the complex adopts a slightly distorted octahedral coordination geometry and is six-coordinated with N2O4 donor set consisting of two nitrogen atoms and four oxygen atoms provided by the ligands of two imidazole molecules,two water molecules and two p-toluenesulfonate ions.The sulfonate group of the PTS ligand remains weak-coordinated and forms a number of hydrogen bonds with water molecules and imidazole ligands.X-ray structural analysis reveals that the coordination molecules are connected to form a 3-D supramolecular framework by electrostatic interaction,weak van der Waals forces,hydrogen bonding and π-π interaction.The thermal behaviour of the title complex was investigated by using DSC and TG-DTG techniques.展开更多
Acetalization of glycol with carbonyl compounds was carded out catalyzed by cupric p-toluenesulfonate. These carbonyl compounds included cyclohexanone, propionoaldehyde, n-butyraldehyde, /so-butyraldehyde, n-valeralde...Acetalization of glycol with carbonyl compounds was carded out catalyzed by cupric p-toluenesulfonate. These carbonyl compounds included cyclohexanone, propionoaldehyde, n-butyraldehyde, /so-butyraldehyde, n-valeraldehyde, benzaldehyde and butanone. Satisfactory results were obtained: the conversions of these carbonyl compounds were more than 90%, the selectivities were higher than 99.1%, only 0.1% mole ratio of catalyst to substrate and 90 min were sufficient in most cases. The catalyst and products were separated easily by phase separation.展开更多
Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial effect.The direct esterification of glycerol with lauric acid is the main method to synthesize GML.In this ...Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial effect.The direct esterification of glycerol with lauric acid is the main method to synthesize GML.In this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was deduced.The isomerization reactions of GML and glycerol dilaurate were investigated.It was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification reaction.The kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.展开更多
Lipophilic antioxidants are used in edible oils and oleaginous foods. Therefore, development of novel lipophilic antioxidant is very important. p-toluenesulfonic acid(PTSA) catalyzed esterification of dihydrocaffeic a...Lipophilic antioxidants are used in edible oils and oleaginous foods. Therefore, development of novel lipophilic antioxidant is very important. p-toluenesulfonic acid(PTSA) catalyzed esterification of dihydrocaffeic acid(DHCA) with hexanol was selected as model reaction to investigate the synthesis of lipophilic antioxidant. The highest yield of hexyl dihydrocaffeate was achieved under the following optimum conditions: 1 mol% PTSA, 1:30 molar ratio of dihydrocaffeic acid to hexanol without molecular sieves at 80 ℃ in 2 h. The relationship between temperature and the forward rate constant gave the activation energy of 22.6 k J/mol, which indicated that PTSA possessed high catalytic activity in the synthesis of hexyl dihydrocaffeate. In addition, the activity of PTSA was not inhibited by the water produced during esterification process. Importantly, this esterification could even proceed smoothly when initial water content was below 5%. In addition, the esterification of a set of phenolic acids could take place efficiently under the same conditions affording the corresponding esters in good to excellent yields. This established method will provide an efficient method for produce lipophilic antioxidants from various natural phenolic acids.展开更多
A novel biomimetic catalyst of complex Cu(p-OTs) 2/ethanolamine(1∶1) was used to oxidize 1,1′-bi-2-naphthol into xanthene derivatives with a relative high yield in a mixed solvents of dimethyl sulfoxide(DMSO) and C...A novel biomimetic catalyst of complex Cu(p-OTs) 2/ethanolamine(1∶1) was used to oxidize 1,1′-bi-2-naphthol into xanthene derivatives with a relative high yield in a mixed solvents of dimethyl sulfoxide(DMSO) and CH 3OH. The studies on the effect of some solvents on the yield of xanthene derivatives indicates that the yield reduces dramatically with the increase of the content of H 2O in the mixed solvents of H 2O and DMSO. No product can be obtained when the content of H 2O is up to 70%. The cyclic voltammetric study demonstrated that the copper ion in complex Cu(p-OTs) 2/ethanolamine(1∶1) is reduced via a two-step one-electron reduction process from Cu(Ⅱ) to Cu in the mixture of DMSO and H 2O. Water as a poor solvent in respect to the reactants probably hampered the coordination of 1,1′-bi-2-naphthol to copper/amine complex and led to the insufficient catalytic efficiency of complex Cu(p-OTs) 2/ethanolamine(1∶1).展开更多
The condensation reaction of formaldehyde and methyl formate to form methyl glycolate and methyl methoxy acetate catalyzed by p-toluenesulfonic acid and different Lewis acid compounds has been investigated. The compos...The condensation reaction of formaldehyde and methyl formate to form methyl glycolate and methyl methoxy acetate catalyzed by p-toluenesulfonic acid and different Lewis acid compounds has been investigated. The composite catalytic system consisting of p-toluenesulfonic acid and NiX2 (X = Cl, Br, I), especially NiI2, exhibited a high catalytic performance for the condensation reaction, the total yield of MG and MMAc was up to 72.37%.展开更多
Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was prod...Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was produced from SPO by esterification process using P-toluenesulfonic acid (PTSA) as acid catalyst in different dosages in presence of methanol to convert free fatty acid (FFA) to fatty acid methyl ester (FAME). Batch esterification process of SPO was carried out to study the influence of PTSA dosage (0.25-10% wt/wt), molar ratio of methanol to SPO (6:1-20:1), temperature (40-80 ℃), reaction time (30-120 min). The effects of those parameters on the yield of crude biodiesel and conversion of FFA to FAME were monitored. The optimum condition for batch esterification process was 0.75% wt/wt, 10:1 molar ratio, 60 ℃ temperature and 60 minutes reaction time.展开更多
1 Results In order to develop high capacity anode materials for enhancing the performance of lithium-ion batteries,silicon (Si) and a variety of metals that alloy with lithium,such as Sn,Sb,and Al,were studied and fou...1 Results In order to develop high capacity anode materials for enhancing the performance of lithium-ion batteries,silicon (Si) and a variety of metals that alloy with lithium,such as Sn,Sb,and Al,were studied and found to be promising candidates as anode materials[1-4].Among them,Si appears to be the most attractive candidate due to its large theoretical lithium insertion capacity of 4 200 mAh g-1[1].Unfortunately,there is one severe problem with the application of Si anode,i.e., the large volume chang...展开更多
A facile, efficient synthesis of 3-(guaiazulen-l-yl)succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.
基金Supported by the Foundation of Key Laboratory for Green Chemical Process of Ministry of Education,Wuhan Institute of Technology (No. RGCT200904)
文摘A novel supramolecular mixed ligand complex of formula [Cu(PTS)2(Him)2(H2O)2] (C20H26CuN4O8S2,PTS=p-toluenesulfonate,Him=imidazole) has been synthesized in aqueous solution and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The compound crystallizes in the monoclinic system,space group P21/n,Z=2,a=5.650(2),b=14.671(3),c=14.638(3),β=100.10(3)°,V=1194.60(4)3,Dc=1.607 g/cm3,μ(MoKα)=1.143 mm-1,F(000)=598,R=0.0615 and wR=0.1503 for 1752 observed reflections with I 〉 2σ(I).The copper(II) ion in the complex adopts a slightly distorted octahedral coordination geometry and is six-coordinated with N2O4 donor set consisting of two nitrogen atoms and four oxygen atoms provided by the ligands of two imidazole molecules,two water molecules and two p-toluenesulfonate ions.The sulfonate group of the PTS ligand remains weak-coordinated and forms a number of hydrogen bonds with water molecules and imidazole ligands.X-ray structural analysis reveals that the coordination molecules are connected to form a 3-D supramolecular framework by electrostatic interaction,weak van der Waals forces,hydrogen bonding and π-π interaction.The thermal behaviour of the title complex was investigated by using DSC and TG-DTG techniques.
基金Project supported by the National Natural Science Foundation of China (No. G2000048).
文摘Acetalization of glycol with carbonyl compounds was carded out catalyzed by cupric p-toluenesulfonate. These carbonyl compounds included cyclohexanone, propionoaldehyde, n-butyraldehyde, /so-butyraldehyde, n-valeraldehyde, benzaldehyde and butanone. Satisfactory results were obtained: the conversions of these carbonyl compounds were more than 90%, the selectivities were higher than 99.1%, only 0.1% mole ratio of catalyst to substrate and 90 min were sufficient in most cases. The catalyst and products were separated easily by phase separation.
基金supported by the National Research and Development Program of China(2021YFC3001100)the National Natural Science Foundation of China(22288102).
文摘Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial effect.The direct esterification of glycerol with lauric acid is the main method to synthesize GML.In this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was deduced.The isomerization reactions of GML and glycerol dilaurate were investigated.It was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification reaction.The kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.
基金Supported by Scientific and Technological Project of Henan Province(No.182102110024)Basic Research Funds of Henan University of Technology(No.2015RCJH01)
文摘Lipophilic antioxidants are used in edible oils and oleaginous foods. Therefore, development of novel lipophilic antioxidant is very important. p-toluenesulfonic acid(PTSA) catalyzed esterification of dihydrocaffeic acid(DHCA) with hexanol was selected as model reaction to investigate the synthesis of lipophilic antioxidant. The highest yield of hexyl dihydrocaffeate was achieved under the following optimum conditions: 1 mol% PTSA, 1:30 molar ratio of dihydrocaffeic acid to hexanol without molecular sieves at 80 ℃ in 2 h. The relationship between temperature and the forward rate constant gave the activation energy of 22.6 k J/mol, which indicated that PTSA possessed high catalytic activity in the synthesis of hexyl dihydrocaffeate. In addition, the activity of PTSA was not inhibited by the water produced during esterification process. Importantly, this esterification could even proceed smoothly when initial water content was below 5%. In addition, the esterification of a set of phenolic acids could take place efficiently under the same conditions affording the corresponding esters in good to excellent yields. This established method will provide an efficient method for produce lipophilic antioxidants from various natural phenolic acids.
文摘A novel biomimetic catalyst of complex Cu(p-OTs) 2/ethanolamine(1∶1) was used to oxidize 1,1′-bi-2-naphthol into xanthene derivatives with a relative high yield in a mixed solvents of dimethyl sulfoxide(DMSO) and CH 3OH. The studies on the effect of some solvents on the yield of xanthene derivatives indicates that the yield reduces dramatically with the increase of the content of H 2O in the mixed solvents of H 2O and DMSO. No product can be obtained when the content of H 2O is up to 70%. The cyclic voltammetric study demonstrated that the copper ion in complex Cu(p-OTs) 2/ethanolamine(1∶1) is reduced via a two-step one-electron reduction process from Cu(Ⅱ) to Cu in the mixture of DMSO and H 2O. Water as a poor solvent in respect to the reactants probably hampered the coordination of 1,1′-bi-2-naphthol to copper/amine complex and led to the insufficient catalytic efficiency of complex Cu(p-OTs) 2/ethanolamine(1∶1).
文摘The condensation reaction of formaldehyde and methyl formate to form methyl glycolate and methyl methoxy acetate catalyzed by p-toluenesulfonic acid and different Lewis acid compounds has been investigated. The composite catalytic system consisting of p-toluenesulfonic acid and NiX2 (X = Cl, Br, I), especially NiI2, exhibited a high catalytic performance for the condensation reaction, the total yield of MG and MMAc was up to 72.37%.
文摘Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was produced from SPO by esterification process using P-toluenesulfonic acid (PTSA) as acid catalyst in different dosages in presence of methanol to convert free fatty acid (FFA) to fatty acid methyl ester (FAME). Batch esterification process of SPO was carried out to study the influence of PTSA dosage (0.25-10% wt/wt), molar ratio of methanol to SPO (6:1-20:1), temperature (40-80 ℃), reaction time (30-120 min). The effects of those parameters on the yield of crude biodiesel and conversion of FFA to FAME were monitored. The optimum condition for batch esterification process was 0.75% wt/wt, 10:1 molar ratio, 60 ℃ temperature and 60 minutes reaction time.
文摘1 Results In order to develop high capacity anode materials for enhancing the performance of lithium-ion batteries,silicon (Si) and a variety of metals that alloy with lithium,such as Sn,Sb,and Al,were studied and found to be promising candidates as anode materials[1-4].Among them,Si appears to be the most attractive candidate due to its large theoretical lithium insertion capacity of 4 200 mAh g-1[1].Unfortunately,there is one severe problem with the application of Si anode,i.e., the large volume chang...
基金the Foundation of Innovation Team Project of Liaoning Education Department(No.2008T001) for financial support
文摘A facile, efficient synthesis of 3-(guaiazulen-l-yl)succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.