Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method for dimethyl dicarbonate

A technology of dimethyl dicarbonate and methyl chloroformate, which is applied in the field of preparation of dimethyl dicarbonate, can solve the problems of not being suitable for actual production, low product purity, long reaction time, etc., and it is not easy to achieve The effect of complete removal, simple process, and short reaction time

Active Publication Date: 2011-10-19
杭州元素添加剂科技有限公司
View PDF4 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] However, filtration is required in the synthesis process, which has certain risks, and the reaction time is long, the yield is low, and the purity of the obtained product is not high, so it is not suitable for actual production.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method for dimethyl dicarbonate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Example 1: In a 2000 ml reaction flask, add 400 g of methyl chloroformate (technical grade), 400 ml of dichloromethane, add 143.82 g of dodecyl dimethyl benzyl ammonium chloride, stir, and cool to 5~ 15°C, add 1166g of 14% sodium hydroxide aqueous solution dropwise, after the dropwise addition, let stand to separate layers, discard the water layer, add 32g of 85% sulfuric acid to the organic layer, stir at room temperature for 1.5 hours, separate layers, add anhydrous magnesium sulfate to the organic layer to dry , filtered, then distilled under reduced pressure, first remove the solvent, and then collect the fraction at 200Pa, 30°C-35°C to obtain 232g of colorless liquid product dimethyl dicarbonate, yield 81.9%, freezing point 17°C, GC purity 99.9 %.

[0028] The acid and alkali solution concentrations mentioned in this embodiment are all mass percentage concentrations, the same below.

[0029] In this example, tri-(dodecyl)methyl ammonium chloride, tri-(tetradecyl)m...

Embodiment 2

[0030] Embodiment 2: in 2000 milliliter reaction bottle, add 400g methyl chloroformate (industrial grade), 380 milliliters of ethylene dichloride, add 11.14g tri-(dodecyl) methyl ammonium chloride, stir, cool to 0~10°C, add 1420g15.8% potassium hydroxide aqueous solution dropwise, after the dropwise addition is completed, let it stand for stratification, add 100g30% hydrochloric acid to the organic layer, stir at room temperature for 1 hour, and separate layers, add anhydrous magnesium sulfate to the organic layer, Dry for 1 hour, filter off the desiccant, distill off the solvent under reduced pressure, and then collect the fraction at 200 Pa, 30°C-35°C to obtain 241 g of colorless liquid product dimethyl dicarbonate, with a yield of 85.2% and a freezing point of 17°C. 99.9% pure.

Embodiment 3

[0031] Example 3: In a 2000ml reaction flask, add 400g methyl chloroformate (technical grade), 400ml benzene, add 10g tri-(tetradecyl)methylammonium chloride, stir, and cool to 15-25°C , add dropwise 1600g of 12.8% potassium hydroxide aqueous solution, dropwise addition, layering, add 30g90% sulfuric acid to the organic layer, stir at room temperature for 1 hour, layering, add anhydrous magnesium sulfate to the organic layer, dry at room temperature for 1 hour, filter off Desiccant, distilled under reduced pressure to remove the solvent, and then collected the fraction at 200Pa, 30°C-35°C to obtain 232g of a colorless liquid product, dimethyl dicarbonate, with a yield of 82.1%, a freezing point of 17°C, and a purity of 99.9%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
freezing pointaaaaaaaaaa
Login to View More

Abstract

The invention discloses a preparation method for dimethyl dicarbonate, and belongs to the technical field of fine chemical industry. The method is characterized in that: in a organic solvent which is insoluble in water, quaternary ammonium salt is adopted as a catalyst, methyl chloroformate and a alkaline solutionare are adopted as raw materials to be subjected to a reaction for 0.5-3 hours at a temperature of 0-25 DEG C; after completing the reaction, the resulting solution is stood for demixing; the resulting organic layer is processed, and is subjected to reduced pressure distillation to collect fractions under pressure of 200 Pa at the temperature of 30-35 DEG C to obtain the product of the dimethyl dicarbonate. With the present invention, the quaternary ammonium salt is adopted as the catalyst, such that complete performance of the reaction is prompted, and the quaternary ammonium salt is easily removed after completing the reaction and is not remained in the product so as to do not influence on purity of the product; tertiary amine used in the prior art is avoided, because the tertiary amine can prompt the reaction, and can also inhibit the reaction when reaction conditions can not be controlled well, and the tertiary amine is difficult to be removed completely and can be remained in the product so as to enable the product to have disadvantages of decomposition and deterioration; reaction yield of the dimethyl dicarbonate is higher than 81%, purity of the dimethyl dicarbonate is high, GC of the dimethyl dicarbonate is more than equal to 99.8%, a solidification point of the dimethyl dicarbonate is 17 DEG C, such that each index of the dimethyl dicarbonate meets requirements of food additives, and the dimethyl dicarbonate is applicable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of fine chemicals, and in particular relates to a method for preparing dimethyl dicarbonate with a high yield by using a quaternary ammonium salt as a catalyst. Background technique [0002] Dimethyl dicarbonate (also known as Vigoline), which has a chemical structure of formula (I), is a food additive for sterilizing beverages. [0003] (I) [0004] American Journal of Organic Chemistry J. Org. Chem., 2000, 65 (24), 8224-8228 DOI: 10.1021 / jo000820u discloses a synthetic method for preparing dimethyl dicarbonate, which consists of triphosgene and methanol reagent The reaction forms phosgene, which is then substituted with methanol and condensed to obtain dimethyl dicarbonate. The method uses extremely toxic triphosgene, and a large amount of hydrochloric acid gas is generated during the reaction process. The method is complex in operation, heavy in pollution, long in reaction cycle and high in cost, and ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07C69/96C07C68/00B01J31/02
Inventor 黄有明孙文龙胡文钢刘田春
Owner 杭州元素添加剂科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com