Method for preparing and purifying hexaalkylguanidine chloride

A purification method and chloride technology are applied in the field of preparation and purification of phase transfer catalyst hexaalkylguanidine chloride, which can solve the problems of difficult high-temperature polymerization of liquids, restricting the application of hexaalkylguanidine salts, affecting polymer quality and the like , to achieve the effect of easy transportation and storage, meeting the requirements of high temperature polymerization, and improving the purity

Active Publication Date: 2012-07-04
SINO HIGH CHINA
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In this method, although the yield of pentaalkylguanidine is relatively high, it cannot be widely used at all due to the extremely strong toxicity of phosgene.
[0008] 3) The Vilsmeier salt prepared by the reaction of tetraalkylurea and phosphorus oxychloride reacts with dialkylamine in one step to generate hexaalkylguanidine salt (Pruszynski P., et al, Canadian Journal of Chemistry, 1987, 65, 626-629 ), the main disadvantage of this method is that phosphorus oxychloride participates in the reaction, making the product contain phosphorus radicals, causing the product to be unable to separate, and causing the pH to be unstable when hexaalkylguanidine is made into an aqueous solution
[0011] The hexaalkylguanidine salts that have been reported to be prepared are generally in a liquid state, especially in an oily state. Because their liquid state contains a small amount of water and phosphate or other impurities, it is difficult to operate under high temperature conditions, which affects the quality of polymers, making Liquids are difficult to use in high-temperature polymerization reactions, which greatly limits the application of hexaalkylguanidine salts

Method used

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  • Method for preparing and purifying hexaalkylguanidine chloride
  • Method for preparing and purifying hexaalkylguanidine chloride
  • Method for preparing and purifying hexaalkylguanidine chloride

Examples

Experimental program
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Effect test

Embodiment 1

[0041] Under nitrogen protection, add tetraethylurea (43g, 0.25mol) in a 500ml four-necked flask equipped with stirring paddle, thermometer, condenser tube and nitrogen inlet tube, dry toluene (25ml), stir to make it dissolve, and Molecular sieves type HZSM-5 (1.25 g) were added. Then a solution of triphosgene (29.7 g, 0.10 mol) in toluene (125 ml) was added dropwise. After the dropwise addition, the temperature was raised to 60° C., and the stirring reaction was continued for 2 h. After the reaction was completed, the temperature was lowered to 0°C. Under nitrogen protection, diethylamine (43.8g, 0.6mol) was added dropwise, the reaction temperature was controlled at 20°C to 26°C, monitored by HPLC, after the reaction was finished, the pH value was adjusted to about 7.5 with 50wt% sodium hydroxide aqueous solution (100ml), Separation, water phase with CH 2 Cl 2 (50ml×5) extraction, combined CH 2 Cl 2 phase, dried over anhydrous magnesium sulfate, and the solvent was disti...

Embodiment 2

[0045] Under nitrogen protection, add tetramethylurea (75.4g, 0.65mol) to a 1L four-necked flask equipped with stirring paddle, thermometer, condenser tube and nitrogen inlet tube, dry toluene (110ml), stir to make it dissolve, And add HZSM-5 type molecular sieve (3.25g). Then a solution of triphosgene (80 g, 0.27 mol) in toluene (300 ml) was added dropwise. After the dropwise addition, the temperature was raised to 60° C., and the stirring reaction was continued for 2.7 h. After the reaction was completed, the temperature was lowered to 0°C. Under nitrogen protection, dropwise add dimethylamine (73g, 1.62mol), control reaction temperature at 20 ℃~26 ℃, HPLC monitors, after reaction finishes, adjust pH value to about 7.5 with 50wt% sodium hydroxide aqueous solution (280ml), divide Liquid, water phase with CH 2 Cl 2 (135ml×5) extraction, combined CH 2 Cl 2 phase, dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain a ye...

Embodiment 3

[0047] Under nitrogen protection, add tetraethylurea (250g, 1.45mol) to a 5L four-necked flask equipped with a stirring paddle, a thermometer, a condenser tube and a nitrogen inlet tube, dry toluene (900ml), stir to dissolve it, add Zeolite H Beta (7.25 g). Then a solution of triphosgene (180 g, 0.61 mol) in toluene (750 ml) was added dropwise. After the dropwise addition, the temperature was raised to 60° C., and the stirring reaction was continued for 3 h. After the reaction was completed, the temperature was lowered to 0°C. Under nitrogen protection, dropwise add diethylamine (270g, 3.70mol), control reaction temperature at 20 ℃~26 ℃, HPLC monitors, after reaction finishes, adjust pH value to about 7.5 with 50wt% sodium hydroxide aqueous solution (660ml), divide Liquid, water phase with CH 2 Cl 2 (300ml×5) extraction, combined CH 2 Cl 2 phase, dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain a yellow oil. It wa...

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Abstract

The invention discloses a method for preparing and purifying hexaalkylguanidine chloride, which includes steps that tetraalkylurea first reacts with triphosgene under the effect of catalyst, then dialkyl amine is added to continue reacting, pH is adjusted through alkali liquor after reaction, then liquid is separated, and finally recrystallization is conducted in mixed organic solvent and the like. The method adopts molecular sieve catalyst, improves conversion rate of triphosgene, and greatly increases product yield. The triphosgene is non-toxic, and safe and reliable to use. The mixed organic solvent is used to recrystallize, not only product purity is improved, but also solid ion phase transfer catalyst is obtained. The method is convenient to operate, does not require special equipment, and is suitable for industrial production, high in product purity and especially suitable for high temperature polymerization.

Description

technical field [0001] The invention relates to a preparation method of hexaalkylguanidine chloride, in particular to a preparation and purification method of a phase transfer catalyst hexaalkylguanidine chloride. Background technique [0002] Guanidine compounds are often used as catalysts in various chemical reactions. Among them, neutral guanidine compounds have a certain basicity, while ionic guanidine compounds (also called guanidine salts) have phase transfer catalytic properties. [0003] There are many kinds of phase transfer catalysts, such as quaternary ammonium salts, phosphorus salts, and aminopyridinium salts. However, because the general polymerization reaction requires relatively high temperature conditions, many catalysts are not stable under such harsh conditions, so it is difficult to play a catalytic role. And when hexaalkylguanidine salt is used as a phase transfer catalyst, it can exist stably under high temperature conditions, so it will not decompose...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C279/04C07C277/08
Inventor 汤浩严留新杲婷张海娟陈年海
Owner SINO HIGH CHINA
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