Method for preparing difluoroacetic acid esters
A technology of difluoroacetate and difluoroacetyl fluoride, which is applied in the preparation of alkyl esters and cycloalkyl esters, and in the field of difluoroacetate preparation, which can solve problems such as pollution and achieve easy-to-achieve effects
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Examples
Embodiment 1
[0080] In Teflon with air inlet and Rushton turbine type agitation system The resulting autoclave was charged with ethanol (50 g, 1.09 mol) and sodium carbonate (116.2 g, 1.1 mol).
[0081] The autoclave was closed and the temperature of the mixture was lowered to 5°C.
[0082] A gas stream of difluoroacetyl fluoride (mass flow rate 190 g / h) was then introduced into the mixture for 30 minutes, keeping the temperature below 15°C.
[0083] The amount of difluoroacetyl fluoride added was 95 g (0.97 mol).
[0084] Stirred at 15°C for 1 hour, then purged the top of the reactor with nitrogen for 30 minutes to return the temperature to room temperature (20°C). The autoclave was then vented.
[0085] The reaction mixture was then filtered and the salts were rinsed with 100 mL of dichloromethane.
[0086] The filtrates were combined and distilled under atmospheric pressure.
[0087] The collected fractions boiled between 96 and 99°C.
[0088] 92 g of ethyl difluoroacetate are ob...
Embodiment 2
[0091] The autoclave described in Example 1 was charged with methanol (80 g, 2.5 mol) and sodium carbonate (270.3 g, 2.55 mol).
[0092] The autoclave was closed and the temperature of the mixture was lowered to 5°C.
[0093] A gas stream of difluoroacetyl fluoride (mass flow rate 190 g / h) was then added to the mixture for 94 minutes, keeping the temperature below 15°C.
[0094] The amount of difluoroacetyl fluoride added was 256 g (2.5 mol).
[0095] Stirred at 15°C for 1 hour, then purged the top of the reactor with nitrogen for 30 minutes to return the temperature to room temperature (20°C). The autoclave was then vented.
[0096] The reaction mixture was then filtered, rinsing the salts with 250 mL of dichloromethane.
[0097] The filtrates were combined and distilled under atmospheric pressure.
[0098] The collected fractions boiled between 85 and 86°C.
[0099] 189 g of methyl difluoroacetate are obtained.
[0100] The yield was 69 wt.%.
Embodiment 3
[0102] The autoclave described in Example 1 was charged with ethanol (50 g, 1.09 mol), xylene (800 mL) and sodium carbonate (477 g, 4.5 mol).
[0103] The autoclave was closed and the temperature of the mixture was lowered to 5°C.
[0104] A mixture of difluoroacetyl fluoride and anhydrous hydrofluoric acid (molar ratio of HF / difluoroacetyl fluoride = 1 / 3.2) was then added to the mixture to keep the temperature below 10°C.
[0105] The amount of difluoroacetyl fluoride added was 105 g (1.07 mol), and the amount of HF added was 68.6 g (3.4 mol).
[0106] Stirred at 15°C for 1 hour, then purged the top of the reactor with nitrogen for 30 minutes to return the temperature to room temperature (20°C). The autoclave was then vented.
[0107] The reaction mixture was distilled under atmospheric pressure.
[0108] The collected fractions boiled between 96 and 98°C.
[0109] 87.8 g of ethyl difluoroacetate are obtained.
[0110] The yield was 65 wt.%.
PUM
Login to view more Abstract
Description
Claims
Application Information
Login to view more - R&D Engineer
- R&D Manager
- IP Professional
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap