Process for the preparation of alkyl 3,3-dialkoxypropionates

A dialkoxy propionate, process technology, applied in the field of continuous process, can solve problems such as difficult to handle ketene

Inactive Publication Date: 2010-09-22
LONZA LTD
View PDF3 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Since the reaction is highly exothermic and large quantities of ketene are diffi

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
  • Process for the preparation of alkyl 3,3-dialkoxypropionates

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046] Embodiment 1: the preparation of methyl 3,3-dimethoxypropionate

[0047] 150 kg / h (1.413 kmol / h) of trimethylorthoformate (Fluka) containing 1.5% by weight of montmorillonite K10 (Süd-Chemie) and 84 kg / h of ketene (ketene content about 70% , the rest is an inert gas, such as N 2 , CO and CO 2 , that is, net ketene about 59kg / h, equivalent to about 1.4kmol / h) simultaneously but separately into 620L injection reactor (see figure 1 ), which was inertized and cooled to an internal temperature of 0°C. Under a nitrogen atmosphere, the reaction mixture was maintained at a temperature of about 0°C and circulated in a loop by a circulation pump. The corresponding portion of the reaction mixture corresponding to the amount of starting material added is continuously passed into the holding tank. After filtration, the purity of the filtrate was determined by GC to be 80% methyl 3,3-dimethoxypropionate, 8% unreacted trimethyl orthoformate, 4% methyl 3-methoxypropionate -2-enoat...

Embodiment 2

[0050] Embodiment 2: the preparation of methyl 3-methoxyprop-2-enoate

[0051] Under a nitrogen atmosphere, 0.2 g (2 mmol) of methanesulfonic acid (Fluka) was added to 150 g of filtrate obtained in a similar manner as described in Example 1 in a distillation apparatus with a round bottom flask (about 85%, 0.86 mol of 3,3-dimethoxypropionate). Under a constant flow of nitrogen, the mixture was heated slowly to 160° C. and the methanol formed was distilled off directly. After 6 hours, the heating was turned off. The methyl 3-methoxy-prop-2-enoate obtained in this way is 88% pure (GC) and can be purified by rectification at 10 kPa. The yield of methyl 3-methoxyprop-2-enoate was 85 g (85%) (K 10kPa =95°C) with a purity of 99% (GC).

Embodiment 3

[0052] Embodiment 3: the preparation of methyl 3-methoxyprop-2-enoate

[0053] The reaction adopts 5 g (content 99%, 34 mmol) of purified distilled methyl 3,3-dimethoxypropionate and 25 mg (0.13 mmol) of p-toluenesulfonic acid monohydrate (Fluka) through a method similar to that of Example 2. way. The crude product obtained contained 91% (GC) of methyl 3-methoxyprop-2-enoate.

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

No PUM Login to view more

Abstract

The present invention relates to a continuous process for preparing alkyl 3,3-dialkoxy-propionates of the formula (RO)2CHCH2CO2R, wherein R is C1-6 alkyl, by reacting ketene with an ortho formate of formula (RO)3CH in the presence of an acidic catalyst, characterized in that the reaction is carried out in a loop reactor.

Description

technical field [0001] The present invention relates to the preparation formula (RO) 2 CHCH 2 CO 2 Continuous process for alkyl 3,3-dialkoxy-propionates of R, where R is C 1-6 alkyl. Background technique [0002] Alkyl 3,3-dialkoxypropionates are important C-3 building blocks which are themselves various products (e.g. pyrimidines, quinolines, uracils, fluvastatin, vitamin A, and agrochemicals such as Herbicide 1-methyl-5-hydroxypyrazole) intermediate. A possible synthetic route of alkyl 3,3-dialkoxypropionate is prepared by reaction of corresponding orthoformate with ketene in the presence of acidic catalyst. Thus, for example, G.Büchi prepared methyl 3,3-dimethoxypropionate in a yield of 19% at a reaction temperature of -70°C (Büchi et al., JAm.Chem.Soc.1973, 95 , 540-545). The preparation of ethyl 3,3-diethoxypropionate is described, for example, in US 2,449,471 (yield 52%) and D. Crosby et al., J Org. Chem. 1962, 27, 3083-3085 (yield rate of 54%). The acidic cat...

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
IPC IPC(8): C07C67/46C07C69/708C07C67/327C07C69/734
CPCC07C67/327C07C67/46Y02P20/582C07C69/734C07C69/708
Inventor 沃尔夫冈·温格科妮莉亚·至代斯勒丹尼尔·佐林格
Owner LONZA LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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