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Modification of poly(vinyl chloride) by aromatic amines: application to the extraction of some metal cation

Mabrouki Adnen, Ammari Fayçel

Polimery

2021

T. 66, nr 7-8

389--398

The reaction of poly(vinyl chloride) (PVC) with various aliphatic amines in 1,4-dioxane has been studied. These reactions led to the formation of new polymers (PVC-L), which were characterized by different spectroscopic methods: differential thermal analysis (DTA) and infrared. The extraction percentages were determined by comparing the initial conductivity of the aqueous solution containing the studied metal with the final conductivity of the aqueous solution at extraction equilibrium. One of the obtained polymers gave an extraction rate of 82.05% for Li +, which underlines the importance of the substitution of chlorine atoms by diethylenetriamine groups. A kinetic study of the extraction shows that the optimal duration of extraction was obtained with the polymer most substituted by diethylenetriamine groups.

Badano reakcję poli(chlorku winylu) (PVC) z różnymi aminami alifatycznymi w 1,4-dioksanie. Reakcje te doprowadziły do powstania nowych polimerów (PVC-L), które charakteryzowano metodami różnicowej analizy termicznej (DTA) i podczerwieni. Procent ekstrakcji określano przez porównanie początkowej przewodności roztworu wodnego zawierającego badany metal z końcową przewodnością roztworu wodnego w stanie równowagi ekstrakcji. Dla jednego z otrzymanych polimerów uzyskano stopień ekstrakcji 82, 05% dla Li +, co podkreśla znaczenie podstawienia atomów chloru przez grupy dietylenotriaminowe. Badania kinetyczne wykazały, że optymalny czas ekstrakcji uzyskano dla polimeru z najbardziej podstawionym grupami dietylenotriaminowymi.

Zastosowanie trietyloaminy w syntezie organicznej

Kowalski P., Sikorska-Jarosz J.

Wiadomości Chemiczne

2003

[Z] 57, 11-12

1133--1162

This review shows examples of application of Et3N in oxidations, eliminations, substitutions, and addition reactions. Triethylamine (Et3N) appears to be most popular organic amine base in organic synthetic chemistry. The popularity comes from its low price along with easiness of removal by distillation. However, Et3N is a very dangerous fire hazard when exposed to the heat, flame, or oxidizers. Their salts with inorganic acids are somewhat insoluble in most organic solvents of low polarity and for that reason may by removed from the reaction media by simple filtration. Examples of application of Et3N in oxidation reactions are shown in ozonolysis of cycloalkene 1-8 [3-5] (figs 1-4-5), and figs 1-6-8 show oxidation of 1-14, 1-16, and 1-18 alcohols, employing activated DMSO [6-12]. Various oxidation processes of hydrazones with iodide in the presence of Et3N are presented in fig. 1-9 [13]. Elimination reactions, concerned mainly with dehydrohalogenations, are described in examples of halogen derivatives of lactone 2-1 [17], ketone 2-3 [18,19], sulfone 2-6 [20], and acids 2-9 and 2-11 [21,22] (figs 2-1-5). Dehalogenation of 2-13 [23], 2-17 [26-28], and 2-22 [31-37] acid chlorides are presented in figs 2-6-8, while formation of nitrile oxides in figs 2-11-13 [38-42]. Competitive dehydrobromination and dehydrochlorination reaction occurs in the presence of Et3N in 1,1,1-trichloro-3-bromo-3-fenylopropane (2-35) is described in fig. 2-15 [44]. Mechanizm and examples of transformation of chlorosulfonyl chlorides are presented in figs 2-17-20 [47-51], and dimerization of aldiminium salts [63] in fig. 2-25 as well. Applications of Et3N in carbon-carbon bond formation in an intramolecular Heck reaction are shown in fig. 3-1 [70-74]. Example of use of Et3N in enolboronation of carbonyl compounds is described in fig. 3-2 [75-78], and additionally, in synthesis of silyl enol ethers can be found in figs 3-3-6 [89-104]. Application of Et3N as the base in neutralizing the acids liberated in preparing diazo ketones and mixed anhydrides are indicated in fig. 3-7 [105-107] and fig. 3-8 [108-117] respectively, while in protecting of hydroxy group in figs 3-9-11 [118-126]. Use of Et3N as the effective catalyst in cyjanoethylation reaction of active methyl group in acetylacetone (4-2) [130] and alkylpyridine methiodides 4-4-5, 4-8-9 [131] are shown in figs 4-1-3, and in isomerization reaction of pyrazolines 4-14 [133] and cycloaddition of indane-1,3-dione (4-16) [134] in figs.4-5?6.