A kind of preparation method of galactopyrate

Abstract

The invention discloses a preparation method of galactopyraldehyde, which specifically comprises the following steps: sodium chloroacetate, sodium hydroxide and isoamyl alcohol are put into a toluene solvent in proportion, and the temperature is raised and refluxed for dehydration reaction. After the reaction is completed, most of the isoamyl alcohol and the toluene solvent are firstly recovered, and then the isoamyl alcohol is completely removed by water vapor, and finally the water is completely removed by toluene to obtain a toluene suspension of sodium isopentyl acetate. A certain amount of propylene chloride and a catalyst are added to the toluene suspension of sodium isopentyl acetate, and the temperature is raised and refluxed for reaction to obtain a crude galactopyraldehyde. The crude galactopyraldehyde is filtered and desalted, and after the excess propylene chloride and toluene solvent are recovered, the galactopyraldehyde finished product is obtained by vacuum distillation. The raw materials of the invention are easy to obtain and non-toxic, the preparation method is simple and easy to operate, the safety is high, and it is easy to industrialize.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis, relates to the preparation of a perfume, and particularly relates to a preparation method of galenic ester. Background Art

[0002] Glycol ester, chemical name is allyl isopentyl acetate, appearance is colorless transparent liquid, is an important synthetic fragrance, with strong fruity, green, slightly pineapple-like galbanum aroma, can add a modern flavor to any flavor, and is widely used in perfume, cosmetics, soap, detergent and other daily flavors and tobacco, soft drinks, food and other edible flavors.

[0003] At present, the industrial production process of galactopyramide basically uses isoamyl alcohol, sodium hydroxide and chloroacetic acid as raw materials to first make isopentyloxyacetic acid, and then esterifies it with allyl alcohol under strong acid catalysis to form galactopyramide. The allyl alcohol used in this process is highly toxic and poses serious harm to people and the environment. IFRA clearly stipulates that the allyl alcohol content in commercial galactopyramide shall not exceed 0.1%, which brings great difficulty to quality control in the production process, and the wastewater containing allyl alcohol involved is also difficult to treat. At the same time, the strong acid used in the esterification reaction seriously corrodes the equipment and produces a large amount of salt-containing wastewater. Summary of the invention

[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a method for preparing galenic acid ester. The raw materials of the present invention are easily available and non-toxic, the preparation method is simple and easy to operate, has high safety, and is easy to industrialize.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for preparing galenic acid comprises the following steps:

[0007] Step 1, adding sodium chloroacetate, sodium hydroxide and isoamyl alcohol into a toluene solvent in proportion, heating and refluxing for dehydration reaction; after the reaction is completed, firstly recovering most of the isoamyl alcohol and toluene solvent, then removing all the isoamyl alcohol through water vapor, and finally removing all the water therein with toluene to obtain a toluene suspension of sodium isopentoxyacetate;

[0008] Step 2, adding a certain amount of propylene chloride and a catalyst to the above-mentioned toluene suspension of sodium isopentyl acetate, heating and refluxing to obtain a crude galactopyrate;

[0009] Step 3, filtering and desalting the crude galactopyramide obtained in step 2, recovering excess propylene chloride and toluene solvent, and performing vacuum distillation to obtain the galactopyramide finished product.

[0010] A further improvement of the present invention is:

[0011] The molar ratio of the sodium chloroacetate, sodium hydroxide and isoamyl alcohol is about 1:1.1-1.3:5; the molar ratio of the sodium chloroacetate to propylene chloride is 1:2-3; and the mass ratio of the sodium chloroacetate to the catalyst is about 1:0.1.

[0012] Furthermore, the catalyst is a tertiary amine compound.

[0013] Furthermore, the catalyst is triethylamine or tributylamine or a mixture of the two.

[0014] Furthermore, the temperature of the heating reflux reaction in step 1 and step 2 is 110-120°C.

[0015] Furthermore, the recovered isoamyl alcohol, toluene, water removed by the reaction, allyl chloride and recovered water can all be reused.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention uses tertiary amine compounds as catalysts instead of strong acid catalysts, and has no serious corrosion to equipment;

[0018] In the present invention, water in each step is effectively utilized and reused, and there is basically no wastewater discharge, and the process is more environmentally friendly;

[0019] The present invention does not use highly toxic allyl alcohol, thereby reducing harm to human health and the environment and making the process safer. DETAILED DESCRIPTION

[0020] The present invention is described in detail below in conjunction with specific embodiments.

[0021] Example 1

[0022] 116.5g of sodium chloroacetate, 44g of sodium hydroxide, and 440g of isoamyl alcohol are added to a certain amount of toluene solvent, and the temperature is raised to reflux for dehydration reaction, and the reaction is terminated when substantially no water is discharged. Most of the isoamyl alcohol and toluene solvent are first recovered, and then a certain amount of water is added, and the isoamyl alcohol is completely removed with water vapor, and then a certain amount of toluene is used to remove the water therein, to obtain a toluene suspension of sodium isoamyl acetate.

[0023] 153 g of propylene chloride and 12 g of triethylamine were added to the above-mentioned toluene suspension of sodium isopentyl acetate, and the temperature was raised to reflux for reaction until the content of sodium isopentyl acetate was less than 0.5%, and the reaction was terminated to obtain a crude product of galactopyrate.

[0024] The crude product was filtered to remove salt, excess propylene chloride and toluene solvent were recovered, and then vacuum distilled to obtain the finished product of galactopyran. The effective amount of the product was 163 g, and the yield was 87.6%.

[0025] Example 2

[0026] 116.5g of sodium chloroacetate, 48g of sodium hydroxide, and 440g of isoamyl alcohol are added to a certain amount of toluene solvent, and the temperature is raised to reflux for dehydration reaction, and the reaction is terminated when substantially no water is discharged. Most of the isoamyl alcohol and toluene solvent are first recovered, and then a certain amount of water is added, and the isoamyl alcohol is completely removed with water vapor, and then a certain amount of toluene is used to remove the water therein, and a toluene suspension of sodium isoamyl acetate is obtained.

[0027] 192 g of propylene chloride and 12 g of tributylamine were added to the above-mentioned toluene suspension of sodium isopentyl acetate, and the temperature was raised to reflux for reaction until the content of sodium isopentyl acetate was less than 0.5%, and the reaction was terminated to obtain a crude product of galactopyrate.

[0028] The crude product was filtered to remove salt, excess propylene chloride and toluene solvent were recovered, and then vacuum distilled to obtain the finished product of galactopyran. The effective amount of the product was 165 g, and the yield was 88.7%.

[0029] Example 3

[0030] 116.5g of sodium chloroacetate, 52g of sodium hydroxide, and 440g of isoamyl alcohol are added to a certain amount of toluene solvent, and the temperature is raised to reflux for dehydration reaction, and the reaction is terminated when substantially no water is discharged. Most of the isoamyl alcohol and toluene solvent are first recovered, and then a certain amount of water is added, and the isoamyl alcohol is completely removed with water vapor, and then a certain amount of toluene is used to remove all the water therein, to obtain a toluene suspension of sodium isoamyl acetate.

[0031] 230 g of propylene chloride and 12 g of triethylamine were added to the above-mentioned toluene suspension of sodium isopentyl acetate, and the temperature was raised to reflux for reaction until the content of sodium isopentyl acetate was less than 0.5%, and the reaction was terminated to obtain a crude product of galactopyrate.

[0032] The crude product was filtered to remove salt, excess propylene chloride and toluene solvent were recovered, and then vacuum distilled to obtain the finished product of galactopyran. The effective amount of the product was 166 g, and the yield was 89.2%.

[0033] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing galenic acid, characterized in that: The following steps are involved: Step 1, adding sodium chloroacetate, sodium hydroxide and isoamyl alcohol into a toluene solvent in proportion, heating and refluxing for dehydration reaction; after the reaction is completed, firstly recovering most of the isoamyl alcohol and toluene solvent, then removing all the isoamyl alcohol through water vapor, and finally removing all the water therein with toluene to obtain a toluene suspension of sodium isopentoxyacetate; Step 2, adding a certain amount of propylene chloride and a catalyst to the above-mentioned toluene suspension of sodium isopentyl acetate, heating and refluxing to obtain a crude galactopyrate; Step 3, filtering and desalting the crude galactopyran product obtained in step 2, recovering excess propylene chloride and toluene solvent, and performing vacuum distillation to obtain the galactopyran product; The catalyst in step 2 is triethylamine or tributylamine or a mixture of the two; The molar ratio of the sodium chloroacetate, sodium hydroxide and isoamyl alcohol is 1:1.1-1.3:5; the molar ratio of the sodium chloroacetate to propylene chloride is 1:2-3; and the mass ratio of the sodium chloroacetate to the catalyst is about 1:0.

1.

2. A method for preparing galenic acid according to claim 1, characterized in that: The temperature of the heating reflux reaction in step 1 and step 2 is 110-120°C.

3. A method for preparing galenic acid according to claim 1, characterized in that: The recovered isoamyl alcohol, toluene, water removed by the reaction, allyl chloride and recovered water can all be reused.