Cross-linked poly(diallyldimethylammonium chloride) and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange reactions....Cross-linked poly(diallyldimethylammonium chloride) and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange reactions.In addition,the effect of hydrophilic-hydrophobic character of the polymers in the nucleophilic reactions was investigated.展开更多
以3-溴丙炔、异氰尿酸为原料,利用相转移催化剂合成了三炔丙基异氰尿酸酯(TPIC),并用FT-IR、1 H NMR对其结构进行了表征。用TGA表征了热固化后的TPIC的热性能。结果表明:热固化后的树脂在375℃开始分解,800℃的残炭率达75%。根据DSC曲线...以3-溴丙炔、异氰尿酸为原料,利用相转移催化剂合成了三炔丙基异氰尿酸酯(TPIC),并用FT-IR、1 H NMR对其结构进行了表征。用TGA表征了热固化后的TPIC的热性能。结果表明:热固化后的树脂在375℃开始分解,800℃的残炭率达75%。根据DSC曲线,TPIC的熔点为167℃左右,并用Kissinger、Flynn-Wall-Ozawa和Friedman-Reich-Levi法分别计算了热固化反应活化能,它们分别为46.81、48.70和40.92kJ.mol-1,热固化反应级数都接近1,并探讨了固化反应过程与机理。通过对比分析表明,这3种方法均适用于TPIC体系。展开更多
We synthesized vinylieriazolyl ketone through Knoevenagel reaction of α-triazolylpinacolone with 4-chlorophenyl acetaldehyde using KF-Al2O3 as a catalyst. The effect of the reaction conditions, such as the amount of ...We synthesized vinylieriazolyl ketone through Knoevenagel reaction of α-triazolylpinacolone with 4-chlorophenyl acetaldehyde using KF-Al2O3 as a catalyst. The effect of the reaction conditions, such as the amount of catalyst, temperature, the molar ratio of 4-chlorophenyl acetaldehyde to α-triazolylpinacolone and different PEGs was investigated. The optimum reaction conditions are: the molar ratio of 4-chlorophenyl acetaldehyde to α-triazolylpinacolone is 1.2∶1, reaction time is 0.5 h, reaction temperature is 75~80℃, the phase transfer is PEG4000. Under these conditions, the yield of vinylieriazolyl ketone could reach up to 95.2%.展开更多
Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cro...Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid occurred efficiently using palladium phosphinous acid complexes (POPd) and phase transfer catalyst (tetrabutylammonium bromide and polyethylene glycol) in water/ethanol mixture, water/propanol mixture and neat water respectively, the corresponding yields of cross-coupling heteroaryl-aryls were satisfied. The tert-butyl substituted ligand di-tert-butylphosphino in combination with POPd was found to be more active than the same family derived catalysts dipalladium complexes POPdl and POPd2, and other two kinds of Pd-catalysts Pd(PPh3)4 and Pd2(dba)3. The mechanism of Suzuki cross-coupling reaction between heteroaryl bromides and phenylboronic acid in water was proposed with respect to the key role of phase transfer catalyst on the transmetallation step. Compared with other solid phase transfer catalysts, TBAB was tested as the ideal one. The alkalinity of base and the molar proportion between POPd and TBAB were investigated in water and alcoholic solvents. Notably, in the presence of TBAB adding alcoholic solvents into water enhanced the yields of target products. However in terms of the liquid phase transfer catalyst of PEGs, mixing water into PEGs could slightly decrease the yields with respect to the water free PEGs bulk phase, which was probably due to the homogenous liquid conditions in pure PEGs and weak interactions between PEGs and heteroaryl bromide molecules in water depending on their molecular chain lengths.展开更多
The Diels-Alder adduct, which is prepared from a phase transfer catalyzed reaction of menadione witb cyclopentadiene, was alkylated with geranyl chloride on sodium amide as a deproteined reagent to form the correspond...The Diels-Alder adduct, which is prepared from a phase transfer catalyzed reaction of menadione witb cyclopentadiene, was alkylated with geranyl chloride on sodium amide as a deproteined reagent to form the corresponding alkylation product, from which vitamin K2(10) is obtained by a retro-DielsAlder reaction.展开更多
文摘Cross-linked poly(diallyldimethylammonium chloride) and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange reactions.In addition,the effect of hydrophilic-hydrophobic character of the polymers in the nucleophilic reactions was investigated.
文摘以3-溴丙炔、异氰尿酸为原料,利用相转移催化剂合成了三炔丙基异氰尿酸酯(TPIC),并用FT-IR、1 H NMR对其结构进行了表征。用TGA表征了热固化后的TPIC的热性能。结果表明:热固化后的树脂在375℃开始分解,800℃的残炭率达75%。根据DSC曲线,TPIC的熔点为167℃左右,并用Kissinger、Flynn-Wall-Ozawa和Friedman-Reich-Levi法分别计算了热固化反应活化能,它们分别为46.81、48.70和40.92kJ.mol-1,热固化反应级数都接近1,并探讨了固化反应过程与机理。通过对比分析表明,这3种方法均适用于TPIC体系。
文摘We synthesized vinylieriazolyl ketone through Knoevenagel reaction of α-triazolylpinacolone with 4-chlorophenyl acetaldehyde using KF-Al2O3 as a catalyst. The effect of the reaction conditions, such as the amount of catalyst, temperature, the molar ratio of 4-chlorophenyl acetaldehyde to α-triazolylpinacolone and different PEGs was investigated. The optimum reaction conditions are: the molar ratio of 4-chlorophenyl acetaldehyde to α-triazolylpinacolone is 1.2∶1, reaction time is 0.5 h, reaction temperature is 75~80℃, the phase transfer is PEG4000. Under these conditions, the yield of vinylieriazolyl ketone could reach up to 95.2%.
基金supported by the Natural Science Foundation of Liaoning Education Department (No. 2008T094)
文摘Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid occurred efficiently using palladium phosphinous acid complexes (POPd) and phase transfer catalyst (tetrabutylammonium bromide and polyethylene glycol) in water/ethanol mixture, water/propanol mixture and neat water respectively, the corresponding yields of cross-coupling heteroaryl-aryls were satisfied. The tert-butyl substituted ligand di-tert-butylphosphino in combination with POPd was found to be more active than the same family derived catalysts dipalladium complexes POPdl and POPd2, and other two kinds of Pd-catalysts Pd(PPh3)4 and Pd2(dba)3. The mechanism of Suzuki cross-coupling reaction between heteroaryl bromides and phenylboronic acid in water was proposed with respect to the key role of phase transfer catalyst on the transmetallation step. Compared with other solid phase transfer catalysts, TBAB was tested as the ideal one. The alkalinity of base and the molar proportion between POPd and TBAB were investigated in water and alcoholic solvents. Notably, in the presence of TBAB adding alcoholic solvents into water enhanced the yields of target products. However in terms of the liquid phase transfer catalyst of PEGs, mixing water into PEGs could slightly decrease the yields with respect to the water free PEGs bulk phase, which was probably due to the homogenous liquid conditions in pure PEGs and weak interactions between PEGs and heteroaryl bromide molecules in water depending on their molecular chain lengths.
文摘The Diels-Alder adduct, which is prepared from a phase transfer catalyzed reaction of menadione witb cyclopentadiene, was alkylated with geranyl chloride on sodium amide as a deproteined reagent to form the corresponding alkylation product, from which vitamin K2(10) is obtained by a retro-DielsAlder reaction.