CN1039411C

CN1039411C - Synthetic method of betaine

Info

Publication number: CN1039411C
Application number: CN93109224A
Authority: CN
Inventors: 马兰宇; 洪昌茂
Original assignee: Beijing Forage Science & Technology Inst
Current assignee: Beijing Forage Science & Technology Inst
Priority date: 1993-08-05
Filing date: 1993-08-05
Publication date: 1998-08-05
Anticipated expiration: 2013-08-05
Also published as: CN1084505A

Abstract

The present invention relates to a synthetic method for betaine by using sodium chloroacetate and trimethylamine as raw materials. A room temperature is used as an initiative reaction temperature. Home-made strong-acidic cation-exchange resin is used as a separation and purification medium for reaction liquid. The method has the advantages of simple and easy operation, short reaction time and favorable effects on separation and purification. Betaine hydrochloride products of which the purity is above 98.5% and the yield is larger than 96% can be prepared.

Description

Method for synthesizing glycine betaine

The invention relates to a synthetic method of glycine betaine in organic synthesis.

Trimethylaminoethyl lactone [ (CH)₃)₃NCH₂COO is commonly known as betaine, and is applied to the fields of medicine, daily chemical industry and the like. In recent years, researches on the application of betaine in the field of feed additives are more and more emphasized. Especially, the molecular structure of betaine contains active nitrogen atoms and rich methyl groups, which are three times more than that of methionine, and can better promote and participate in biochemical reaction in animal bodies. It is possible to replace methionine, which is used for the synthesis of endosomal proteins in animals and is an essential amino acid most widely and used in animal husbandry, and plays an important role in animal husbandry and aquaculture. The source of betaine can be waste residue, waste honey and waste of sugar production from beetThe extraction in the liquid is an economic way, but is limited by seasons and regions, namely, the production must be arranged in the harvest season and the production place of the beet. The other way is to prepare the compound by a chemical synthesis method, and the compound can not be limited by the above. The synthesis of betaine is usually carried out by using sodium chloroacetate (or reacting chloroacetic acid with sodium hydroxide) and trimethylamine as raw materials, as described in the handbook of Fine organic chemistry techniques (scientific Press 1992, 293). The disadvantages of using this synthesis method are: the initial temperature of the chemical reaction is required to be rapidly raised to 38 ℃, so that part of trimethylamine (the boiling point is 3.6 ℃) is easy to volatilize without taking part in the reaction; the method is used for introducing air during reaction, so that a reaction system requires a closed device for ensuring the air introduction; and the DOWEx-50 multiplied by 8 resin adopted for purifying and separating the reaction solution is acidic cation exchange resin produced by the United states DOWEx company, has strong technical pertinence and is not easy to obtain in domestic markets.

The invention aims to overcome the defects in the prior art and provide an improved, simple and feasible synthesis method to meet the increasing requirements on betaine in the fields of medicine, daily chemical industry, particularly livestock and aquatic product breeding.

The synthesis method of trimethylamine ethylene lactone is technically characterized in that room temperature is used as the initial temperature of the reaction, air is not needed to be introduced for the reaction in the reaction process, and common domestic strong acid cation exchange resin which is easy to obtain is used as a separation and purification medium of the reaction liquid. The specific synthesis steps are as follows:

a. chemical reaction

Dissolving sodium chloroacetate in2.5 to 3.5 times of water is put into a reactor provided with a stirring reflux condenser, 33 percent trimethylamine aqueous solution is added according to the equivalent ratio of 1: 1 to 1.1 of sodium chloroacetate to trimethylamine under stirring, the mixture reacts for 20 to 30 minutes at room temperature, the mixture is heated by a water bath, the temperature is raised to enable the reaction solution to react for 1 hour at 52 to 54 ℃, then boiled water is added into the water bath to adjust the temperature to 70 to 85 ℃ for reaction for 1 hour, and the reaction solution is naturally cooled. Chamber according to the inventionThe temperature is 20-28 ℃.

b. Separation and purification

And pouring the cooled reaction solution into an ion exchange resin column, rinsing with water, rinsing with 3-10% ammonia water, collecting the solution containing the glycine betaine, and controlling the flow rate to be 5-20 mL/min. When the material without betaine or the regenerated ion exchange resin column is leached with water, the flow rate is not required to be controlled, and the leaching can be carried out quickly. The ion exchange resin is domestic strong acid cation resin, the volume of ion exchange resin column is phi 6 × 80cm, and the water is distilled water or deionized water

The sodium chloroacetate is chemically pure or industrially pure, and a 33% trimethylamine aqueous solution can be directly purchased from the market.

c. Concentration and salting out

Evaporating and concentrating the effluent containing betaine to 1/4 volume, adding equivalent hydrochloric acid, stirring, concentrating to separate solid powder, vacuum drying at 80-95 deg.C, and drying under reduced pressure to remove trace water to obtain betaine hydrochloride product which is easy to be stored in air and is not hygroscopic. Purity) 98.5%, yield) 96% (normally betaines are protected from moisture and are stored as the hydrochloride salt).

The aqueous solution of sodium chloroacetate in the synthesis method of the present invention can also be replaced by a solution obtained by adding aqueous solution of chloroacetic acid and sodium hydroxide to neutralize the solution until the pH value is 6, and the synthesis steps are carried out.

The invention relates to a method for synthesizing betaine, which adopts the measures of lower initial reaction temperature and water bath temperature control instead of direct heating, stirring and simultaneous reflux condensation, reduces volatilization of trimethylamine, enables the trimethylamine to effectively participate in the reaction, shortens the reaction time, does not need to be reacted by air, simplifies equipment, particularly adopts low-price common domestic strong acid cation exchange resin as a filling medium of an ion exchange column to replace DOWEx-50 x 3 resin, enables the method for synthesizing betaine to be simple and easy, and proves that the improved synthesis method is simple to operate, complete in reaction, good in separation and purification effects, and can prepare products with the purity of more than 98.5% and more than 96.3.The product can completely meet the requirements of various fields.

Example 1

Taking 116.5 g of sodium chloroacetate, adding 330ML distilled water for dissolving in a reaction bottle, installing a reflux condenser tube, rapidly adding 180ML of aqueous solution of 33% trimethylamine solution into the sodium chloroacetate solution through a long-neck dropping funnel (inserted below the liquid level) under stirring (180 r/min), reacting at 26 ℃ for 30 minutes at room temperature, heating the water bath to 52 ℃ for reacting at constant temperature for 1 hour, discharging the water in the water bath kettle, replacing the water with boiled water to ensure that the water temperature rapidly reaches 80 ℃, reacting for 1 hour, removing the water bath, and naturally cooling. Pouring the reaction solution into a strong acid cation exchange resin column, leaching with water (to obtain 200-2000mL of wastewater), washing with 5% ammonia water, and collecting about 2000mL of betaine-containing solution, wherein the flow rate is controlled at 6 mL/min. Evaporating the solution to 500mL, adding 80mL concentrated hydrochloric acid, stirring thoroughly, concentrating to 150mL, turning out solid powder, placing into 80 deg.C vacuum drying oven when the moisture is slight, drying under reduced pressure to remove slight water to obtain betaine hydrochloride 151.79 salt with melting point of 243 deg.C, purity of 98.84%, and yield of 99.21%. The molecular structure is basically consistent with the contrast molecular structure of an imported standard sample through infrared spectrum measurement.

Example 2:

350mL of sodium chloroacetate solution containing 1 equivalent; the stirring speed is 170 rpm; the room temperature is 22 ℃; 190mL of 33% trimethylamine solution was added rapidly to a total volume of 640mL, the reaction was carried out for 20 minutes, the temperature was raised to 52 ℃ for 10 minutes, and the reaction was carried out for 1 hour at constant temperature. The same separation and purification method as that of example 1, 650mL of wastewater was collected, 2700mL of the solution with betaine collected was discarded; concentrating to 500mL, adding 83mL concentrated hydrochloric acid, concentrating again, and vacuum drying to remove water to obtain 152.2 g of white powder of hydrochloride of trimethyl ammonium ethylene propylene ester.

Example 3:

189 grams of chloroacetic acid was weighed and neutralized with 510mL of NaoH 4N at PH 6; the method comprises the steps of 1, stirring at 190 rpm at room temperature of 25 ℃, adding 365mL of 33% methylamine water solution into 160mL of water, adding 1035mL of total volume, reacting for 30 minutes, heating to 52 ℃, reacting for 1 hour at constant temperature, heating to 84 ℃, reacting for 1 hour, and naturally cooling; separating and purifying by strong acid cation exchange resin, collecting 2000mL of waste water, collecting 4450mL of betaine solution, concentrating to 400mL, adding 160mL of concentrated hydrochloric acid, and drying to obtain 314 g of white powder product.

Claims

1. A synthetic method of glycine betaine is characterized in that room temperature is used as reaction starting temperature, strong acid cation exchange resin is used as a separation and purification medium of reaction liquid, and the synthetic method comprises the following steps:

(a) chemical reaction:

dissolving sodium chloroacetate in 2.5-3.5 times of water, placing the solution into a reactor provided with a stirring reflux condenser, adding a 33% trimethylamine aqueous solution according to the equivalent ratio of the sodium chloroacetate tothe trimethylamine of 1: 1-1.1 under stirring, reacting for 20-30 minutes at room temperature, reacting for 1 hour at 50-54 ℃, reacting for 1 hour at 70-85 ℃, wherein the room temperature is 20-28 ℃;

(b) separation and purification:

pouring the reaction solution into an ion exchange resin column, leaching with water, washing with 3-10% ammonia water, collecting the solution containing glycine betaine, and controlling the flow rate to be 5-20 ml/min;

(c) concentration and hydrochlorination:

when the solution is evaporated and concentrated to 1/4 volumes, equivalent hydrochloric acid is added and fully stirred; concentrating, turning into solid powder, and drying and dehydrating in vacuum drying oven at 80-95 deg.C.

2. The method for synthesizing trimethylammoniumethyl ester as claimed in claim 1, wherein in the step (a), sodium chloroacetate is dissolved in 2.5-3.5 times of water, and the solution can be neutralized by adding aqueous solution of sodium hydroxide with chloroacetic acid until P is reached^HAqueous solution of 6 instead.