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1.
Stela Drgan I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1972,10(10):3077-3088
The kinetics of the amination of chloromethylated polystyrene with two hydroxyalkylic tertiary amines (1-dimethyl-amino-3-propanol and 1-dimethylamino-2-propanol) in dimethylacetamide and dioxane was studied. The amination of benzyl chloride with the two amines in dimethylacetamide was followed. It was found that the amination of chloromethylated polystyrene is a two-step reaction taking place with different rates. The rate constants k1 and k2 were calculated for the two stages, and a self-accelerating effect of the reaction was noticed. Also, the influence of the position of the hydroxyl group versus the tertiary nitrogen was investigated. The increase of the dielectric constant of the solvent favorably influences the reaction rate. 相似文献
2.
Stela Drgan I. Petrartu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1980,18(7):2333-2346
The reaction of chloromethylated polystyrene with methyl(2- hydroxyethyl)amine and butyle (2-hydroxyethyl)amine was studied kinetically. The reaction of benzyl chloride with these amines was also investigated for comparison. N,N-dimethylformamide and dioxane were used as solvents. The reactions of benzyl chloride with the two amines in these solvents took place according to normal kinetics of the second order. Reaction kinetics depend on the nature of the amine and solvent in Chloromethylated polystyrene reactions. In dioxane the self-accelerating effect of the reaction for β ? 0.5 is apparent. Steric hindrance of the reaction, beginning with a conversion degree of about 75%, wss observed for butyl(2-hydroxyethyl)amine in N,N-dimethylformamide. This self-accelerating effect is observed in dioxane at the same reaction degree. The activation energies and frequency factors were calculated for the amination of benzyl chloride and chloromethylated polystyrene with the two amines in N,N-dimethylformamide and dioxane. 相似文献
3.
A highly selective phosphine-based ruthenium catalyst system efficiently catalyzes the direct amination of alcohols with aliphatic tertiary amines, yielding unsymmetric tertiary amines in yields up to 87%. Ligand and solvent both affect the reaction yields significantly. The reaction can be performed with a wide variety of functionalities. 相似文献
4.
Stela DrÎgan Cornelia Luca I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1980,18(2):455-465
The reaction of chloromethylated polystyrene with tris(2-hydroxyethyl)amine in N,N-dimethylformamide is described for the conditions to prepare soluble reaction products. The groups of the quaternary ammonium salt, which appear in the first stage of the reaction, transpose to the amino-ether groups. The reaction was followed by elementary analysis, IR and 1H-NMR spectra, and viscosimetric measurements for nondialyzed and dialyzed samples. The presence of the tertiary amine groups on obtained polymers was also shown by titration. The polymers from the reaction of chloromethylated polystyrene with tris(2-hydroxyethyl)amine reacted easily with benzyl chloride. 相似文献
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By employing quaternary ammonium salts as catalysts, the carboxylative cyclization of the propargylic amines with CO2 proceeded to afford the corresponding 2-oxazolidinones. In particular, tetra-n-butylammonium fluoride was the most effective catalyst for the reaction, providing a 2-oxazolidinone derivative in a maximum chemical yield of 99%. From a screening of the structure of a catalyst, it was found that both a quaternary ammonium cation and a basicity of the counter anion were essential to catalyze the carboxylative cyclization of the propargylic amines with CO2. 相似文献
7.
An efficient metal-free procedure for the synthesis of tertiary amines by the reductive amination of carbonyl compounds is reported, which allows a convergent access to sterically hindered amines of the general formulas NR(R′)2 and NRR′R″. The mild and operationally simple protocol uses the Hantzsch ester for transfer hydrogenation and catalytic amounts of thiourea for imine activation. 相似文献
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We have developed a catalytic allylic amination involving tertiary aminoesters and allylcarbonates, which is the first example of the use of tertiary amines as intermolecular nucleophiles in metal-catalyzed allylic substitution chemistry. This process is employed in a tandem ammonium ylide generation/[2,3]-rearrangement reaction, which formally represents a palladium-catalyzed Stevens rearrangement. Low catalyst loadings and mild reaction conditions are compatible with an unprecedented substrate scope for the ammonium ylide functionality, and products are generated in high yields and diastereoselectivities. Mechanistic studies suggested the reversible formation of an ammonium intermediate. 相似文献
10.
Rucker RP Whittaker AM Dang H Lalic G 《Journal of the American Chemical Society》2012,134(15):6571-6574
A method for highly selective anti-Markovnikov hydroamination of terminal alkenes is reported. The one-pot procedure involves hydroboration of the alkene followed by a novel electrophilic amination of the alkyl borane catalyzed by an NHC-Cu complex. Terminal alkenes are successfully transformed into tertiary alkyl amines in the presence of a variety of functional groups in yields ranging from 80 to 97% with excellent regioselectivity. Results of a preliminary study of the reaction mechanism are also described. 相似文献
11.
Hong-Bing Tsai Yu-Der Lee 《Journal of polymer science. Part A, Polymer chemistry》1987,25(8):2195-2206
The kinetics of interfacial polycondensation of bisphenol A with isophthaloyl chloride and terephthaloyl chloride in dichloromethane with triethylbenzylammonium chloride (TEBAC) as the catalyst was investigated via measurements of bisphenolate concentration by UV. The reaction was found to be second order with respect to bisphenolate. The dependence of the rate constant on stirring speed, amount of TEBAC, and reaction temperature was studied. The rate constant was increased with an increase of stirring speed, quantity of TEBAC added, as well as the reaction temperature. The activation energy was found to be 7.7 kcal/mol at a stirring speed of 700 rpm in the presence of 0.160 of TEBAC. The role of TEBAC was found to be interesting. It did not alter the equilibrium (the partition coefficient remained the same in the presence of TEBAC), but it did enhance the transfer rate of bisphenolate. 相似文献
12.
Cornelia Luca V. BÎrboiu I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1980,18(7):2347-2355
It was found that the addition reaction between poly(4-vinylpyridinium chloride) and electrophilic vinyl compounds, such as acrylic acid, acrylamide, methylacrylate, and acrylonitrile. leads to ammonium quaternary polymers with a transformation degree that depends oil the reactivity of vinyl compounds. The structure of addition compounds was established by using 1H-NMR IR, and UV spectral methods. NMR-determined values of transformation degree indicate that the reactivity of vinyl compounds decreases as follows: 相似文献
13.
K. Kishore V.R. Pai Verneker V. Gayathri 《Journal of Analytical and Applied Pyrolysis》1980,1(4):315-322
Polystyrene peroxide has been synthesized and its decomposition has been studied by thermogravimetry and differential thermal analysis. Polystyrene peroxide has been found to decompose exothermically at about 110°C. The activation energy for the decomposition was estimated to be 30 kcal/mole both by the Jacobs and Kureishy method and by fitting the α versus time curves to the first-order kinetic equation. This suggests that the rate-controlling step in the decomposition of polystyrene peroxide is cleavage of the OO bond. 相似文献
14.
Tetsuji Kametani Kazuo Kigasawa Tetsutaro Hayasaka Mineharu Hiiragi Haruhide Ishimaru Setsu Asagi 《Journal of heterocyclic chemistry》1966,3(2):129-136
The alkylation of tertiary amines, namely, 2-dimethylaminoethanol, triethylamine, pyridine and isoquinoline with various alkyl carboxylates was investigated. This reaction afforded the corresponding quarternary ammonium salts, e.g., methylation of 2-dimethyl-aminoethanol with methyl salicylate. 相似文献
15.
The reactions of 1,2-dichloroethane with 2-(ethylamino)ethanol or diethylamine have been investigated in several solvents from 51 to 80°C. A reaction mechanism has been proposed where 1,2-dichloroethane reacts with the secondary amines in both bimolecular substitution (SN 2) and elimination (E2) reactions; the substitution product is rapidly converted in an aziridinium ion and undergoes a consecutive reaction with the starting amine to give a tetrasubstituted ethylenediamine. The rate constants as well as the activation energies of these reactions have been determined. © 1994 John Wiley & Sons, Inc. 相似文献
16.
《中国化学快报》2017,(3)
A concise and efficient approach was developed for the synthesis of mono-substituted and di-substituted pyrimidines products via palladium-catalyzed amination of chloro-substituted 5-nitropyrimidines and amines. This synthetic methodology can produce various di-substituted pyrimidines in high yields with good functional group tolerance, and provide a complementary tool for the syntheses of important intermediates of nucleosides and purines with bioactivities. 相似文献
17.
A procedure was developed for the synthesis of tertiary phosphine oxides by alkylation of secondary phosphine oxides with
quaternary ammonium salts.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 390–392, February, 1999 相似文献
18.
Conclusions Some complexes of trinitratoborane with tertiary amines were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1883–1884, August, 1979. 相似文献
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The extractability of antimony(III) and (V) with tridodecylamine from various aqueous solutions is reported. Extraction from nitric and hydrofluoric acid solutions is low, but extraction from sulphuric, hydrochloric and hydrobromic solutions is high. Antimony-(III) can be separated from antimony(V) in 7M nitric acid or 0.64M hydrobromic acid. The extraction of antimony from hydrochloric acid solutions in methanol, ethanol, and acetone-water mixtures is greater than from pure aqueous solutions of the same acidity. The elements from which antimony can be separated with tertiary amines are given. 相似文献