JPS62242638A - Production of chlorinated ether compound - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a raw material for organic industries advantageously, by hydrochlorinating hydroxyl group of diethylene glycol and 2-(2'-chloroethoxy)ethanol with hydrogen chloride in the presence of a carboxylic acid such as acetic acid, adipic acid, etc. CONSTITUTION:In chlorinating hydroxyl group of an ether compound shown by formula I (R is OH or Cl), namely, diethylene glycol and 2-(2'-chloroethoxy) ethanol,, with hydrogen chloride, preferably 0.1-10wt% based on the compound shown by formula I of one or more carboxylic acids (e.g. benzoic acid, caproic acid, etc.) selected from carboxylic acid, especially 1-15C mono- or polycarboxylic acids, 6-15C alicyclic mono- or polycarboxylic acids, 7-15C aromatic mono- or polycarboxylic acids and hetero ring-containing mono- or polycarboxylic acids is present to give a chlorinated compound [e.g. 2-(2'- chloroethyoxy)ethanol, etc.] shown by formula II.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to an advantageous method for producing chlorinated ethyl ethers useful as organic industrial raw materials.

"Prior art" Methods using thionyl chloride, phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride, etc. have been put into practical use for chlorinating alcoholic hydroxyl groups, and these methods have been used to chlorinate alkylene glycols, chloroalkyl It is also well known to chlorinate hydroxyl groups such as oxyalcohols.

However, in such a method, the chlorinating agent as mentioned above is expensive, the utilization rate of chlorine in the chlorinating agent is low, and there are also problems such as toxicity, high handling risks, or post-reaction There were drawbacks such as the generation of large amounts of waste.

On the other hand, the hydroxyl group of diethylene glycol was chlorinated and 2-(
In order to advantageously produce (2'-chloroethoxy) ethanol, a method using hydrogen chloride as a chlorinating agent in order to avoid the above-mentioned drawbacks is disclosed in JP-A-58-67638 and JP-A-58-109441. Disclosed.

However, in the case of ethers such as diethylene glycol used for the former, there is a marked tendency for the main chain to be cleaved by hydrogen chloride, resulting in a significant amount of ethylene glycol, which is difficult to separate from the target compound, produced as a by-product. The yield of -(2'-chloroethoxy)ethanol decreases, which is undesirable, and in the latter case, 2-(2'-
Since it is difficult to separate this by-product glycol from ethanol (chloroethoxy), it must be extracted using a specific extractant to purify it.

Complicated operations such as further distillation and purification were unavoidable.

Furthermore, when di(2-chloroethyl) ether is produced by chlorinating this 2-(2'-chloroethoxy)ethanol with hydrogen chloride, ethylene glycol is produced as a by-product in the same manner as above, and the desired 2 It was difficult to separate it from -(2'-chloroethoxy)ethanol.

[Problems to be Solved by the Invention] Considering the above points, when producing a specific chlorinated ethyl ether, even if hydrogen chloride is used as the chlorinating agent, it is difficult to combine it with the target product such as ethylene glycol. By-products that are difficult to separate are extremely reduced.

Therefore, we investigated ways to easily purify the product.

Means for Solving the Problem 1. In other words, 1. the present invention is to convert the hydroxyl group of the ether compound represented by the following general formula [I] into RC)l CH, OCH, CI, OH
--- [I1 [Here, R represents a hydroxyl group or a chlorine atom.

] When chlorinating using hydrogen chloride, the following general formula [■ is characterized in that a carboxylic acid is present]
I2CH, OCH, (Jl, (1-------1----
[I1] [Here, R is the same as above. This is a method for producing a chlorinated ether compound.

Specifically, the compound represented by the above general formula [I], which is a raw material used in the present invention, is diethylene glycol and 2-(2'-chloroethoxy)ethanol.

These are chlorinated according to the method of the present invention, and the former is 2- (2
'-chloroethoxy)ethanol and the latter di(2-
(chloroethyl) ether.

The chlorinating agent used in the present invention is hydrogen chloride, as mentioned above, and when used, it may be used alone or in an aqueous solution, or in other words, in the form of hydrochloric acid, but it is better to use it alone to obtain the desired product. Selectivity is improved, which is preferable.

The carboxylic acids used in the present invention are as described above.

Any compound having 11 -COO groups may be used, but preferably aliphatic mono- or polycarboxylic acids having 1 to 15 carbon atoms, alicyclic mono- or polycarboxylic acids having 6 to 15 carbon atoms, and 7 to 15 carbon atoms. 15 aromatic mono- or polycarboxylic acids and mono- or polycarboxylic acids with heterocycles, examples of which are formic acid, acetic acid, propionic acid, butyric acid,
Aliphatic carboxylic acids such as valeric acid, caproic acid, lauric acid, oxalic acid, malonic acid, adipic acid, sebacic acid, dodecanedioic acid, acrylic acid, and crotonic acid; alicyclic acids such as cyclohexanedicarboxylic acids and cyclododecane monocarboxylic acid Examples include aromatic carboxylic acids such as benzoic acid, toluic acid, terephthalic acid, trimellitic acid, oxybenzoic acids, and naphthalene carboxylic acid. These carboxylic acid residues may be substituted with a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a mercapto group, an aromatic group, a cyano group, or the like. Furthermore, as these carboxylic acids, amino acids; carboxylic acids having various heterocycles such as furan, thiophene, pyrrole, and pyridine are also preferably used. Further, it is also possible to use polymers having a carboxylic acid fraction such as polyacrylic acid, various carboxylic acid type ion exchange resins, and highly activated derivatives thereof such as acid anhydrides, chlorides and esters.

The amount of the above carboxylic acid or derivative used is 0.1-1O based on the compound represented by the general formula [I] as a raw material.
% by weight, preferably 0.5 to 5% by weight.

There are no particular limitations on the method in carrying out the method of the present invention, but 1. For example, a method of continuously or intermittently adding hydrogen chloride into the compound represented by the above general formula [I], Examples include a continuous system in which a mixture of hydrogen chloride is supplied to the reaction system. Furthermore, if necessary, in addition to a solvent inert to the reaction or the above-mentioned carboxylic acid, other additives or catalysts may be present in the reaction system.

Solvents that can be used include halogenated hydrocarbons,
Examples include various hydrocarbons such as hexane, heptane, octane, benzene, toluene, and xylene.

Examples of additives other than carboxylic acids include Lewis acids for promoting reactions, such as metal halides such as aluminum, zinc, iron, tin, titanium, antimony, and magnesium.

The reaction humidity is preferably 50 to 150°C, particularly 80 to 120°C.

At a temperature lower than 50°C, the reaction is extremely slow, and at a temperature higher than 150°C, impurity by-products are produced significantly, and carbide formation is also observed, both of which are undesirable.

There is no particular limitation on the reaction pressure, and the reaction can be carried out in a wide range from reduced pressure to increased pressure; however, in consideration of the reaction rate, it is preferable to proceed with the reaction under slightly increased pressure.1 Usually 5k
A pressure of less than g/ff1-G is sufficient.

In the method of the present invention, the chlorinating agent is hydrogen chloride, as described above, and the amount used should vary depending on the embodiment of the method. For example, assuming a method in which hydrogen chloride is added to the compound represented by the general formula [■], that is, a mixture of diethylene glycol or 2-(2'-chloroethoxy)ethanol and the aforementioned carboxylic acid, the hydroxyl group-containing compound Hydrogen chloride may be added until all of the 2-(2'- chloroethoxy)
Ethane dichloride tends to be a significant by-product from ethanol, so the amount of hydrogen chloride added is determined by controlling the amount of hydrogen chloride that is produced after the reaction to produce the desired product and by-product (which can also be isolated as a useful compound in some cases). It should be determined by taking into account the composition of Similarly, the rate of addition of hydrogen chloride, reaction temperature, and reaction pressure also affect the above composition, so these should be taken into consideration when determining the composition.

If hydrogen chloride remains in the reaction mixture thus prepared according to the method of the invention, it can be removed under reduced pressure or
The desired 2-(2
'-Chloroethoxy)ethanol or di(2-chloroethyl)ether may be isolated and used as a product.

"Examples" The present invention will be explained in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited thereto.

In the following description, "r parts" indicates parts by weight unless otherwise specified.

Example 1 106 parts of diethylene glycol and 1.2 parts of acetic acid were added to a 200-volume glass flask, and a thermometer, a stirrer, and a condenser were attached to the flask, and the flask was stirred and heated. When the temperature inside the flask reached 100°C, hydrogen chloride gas was added at 9°C per hour.
．． One reaction was carried out by introducing at a rate of 6 parts for 5 hours.

After the reaction was completed, the system was cooled to 80°C, the pressure was reduced, and the 100 m
Hydrogen chloride gas was driven off at mHg for 30 minutes. The weight of the reaction solution at this point was 136.1 parts, and when analyzed by gas chromatography, it was found that diethylene glycol was 37.6 tzt.
%2-(2'-chloroethoxy)ethanol 28.2
wt% ethylene chlorohydrin 17.6
wt% di(2-chloroethyl)ether 3.5
wt% and ethylene glycol 0.3 tit%
composition, and the production of ethylene glycol was extremely low.

The conversion rate of diethylene glycol calculated from the above results was 51.7%, and 2-(2'-chloroethoxy)
The selectivity for ethanol was 59.6%, and the selectivity for ethylene chlorohydrin was 28.7%.

Excess hydrogen chloride was neutralized by adding 2.3 parts of sodium carbonate to this reaction solution, and the mixture was purified using a Widmer-type rectification column with a length of 300 Wl, resulting in a purity of 99.3% and an ethylene glycol content of 0. 38.2 parts of .5% 2-(2'-chloroethoxy)ethanol were obtained. The yield based on the diethylene glycol used was 30.7%.

Comparative example 1 Example 1 was repeated without the addition of acetic acid.

Analysis of the reaction solution revealed that the conversion rate of diethylene glycol was 45.3%, the selectivity of 2-(2''-chloroethoxy)ethanol was 51.8%, and the selectivity of ethylene chlorohydrin was 28.2%. Moreover, the content of ethylene glycol was as high as 3.2 wt%.

When this reaction solution was purified in the same manner as in Example 1, 2-
Although 36.7 parts of (2'-chloroethoxy)ethanol was obtained, the content of ethylene glycol was as high as 2.9%. Moreover, the yield based on the diethylene glycol used was as low as 10.6%.

Comparative Example 2 32 parts of diethylene glycol was placed in a glass flask equipped with a thermometer, a stirrer, a gas inlet tube, and a reflux tube.

While cooling the liquid, 11 parts of hydrogen chloride gas was supplied from the gas inlet pipe and absorbed. Next, the temperature was raised to 100°C, and then the reaction was carried out at 100°C for 5 hours. Thereafter, the reaction was completed by cooling.

The weight of this reaction solution was 41 parts, and it was analyzed using a gas chromatograph.

Diethylene glycol 36.7%+t
%2-(2″-chloroethoxy)ethanol 26.
4wt% di(2-chloroethyl)ether 3
．． 6wt% ethylene glycol 3.
Out% ethylene chlorohydrin 6,9
wt% composition, and a large amount of by-products were present.

The yield of 2-(2'-chloroethoxy)ethanol in the reaction solution was 28.9% (based on diethylene glycol).

Example 2 530 parts of diethylene glycol, 5.0 parts of aluminum chloride, and 5.5 parts of adipic acid were placed in a 1000-volume glass autoclave, and the mixture was stirred and heated. after that.

The pressure in the system was reduced to 100 μ/Hg at 100°C, and hydrogen chloride gas was immediately introduced at a rate of 60 parts/Hr to bring the reaction pressure to normal pressure, and then the maximum pressure was increased to 1.0 kg/cd-G. It took 5 hours to continuously introduce hydrogen chloride gas in a total amount of 159 parts.

After the introduction, the autoclave was opened and the reaction solution was analyzed using a gas chromatograph, and the conversion rate of diethylene glycol was 53.4%, 2-(2ξchloroethoxy).
The selectivity of ethanol is 60.4%, the selectivity of ethylene chlorohydrin is 27.8%, and the content of ethylene glycol is 0. lvt%.

The reaction solution was dehydrochlorinated under reduced pressure and subsequently distilled and purified.
-(2'chloroethoxy)ethanol 199.7 parts (purity 99.1%) was obtained. This contained only 0.2% ethylene glycol, and it had almost no effect on the yield during distillation. The yield of this product based on the diethylene glycol used was 32.0%.

Example 3 106 parts of diethylene glycol and 3.0 parts of benzoic acid were added to a 300-volume glass flask, and to this was added 114 parts of aqueous trichloric acid solution with stirring, and the mixture was reacted at 100° C. for 4 hours. Analysis of the reaction solution revealed that the conversion rate of diethylene glycol was 35.6% and 2-(2'-chloroethoxy).
The selectivity of ethanol was 52.6%, and the content of ethylene glycol was Q, 5 wt%. This reaction solution was distilled under reduced pressure to obtain 23.0 parts of 2-(2'-chloroethoxy)ethanol with a purity of 99.2%. The yield of this product based on the diethylene glycol used was 18.5%.

Example 4 623 parts of 2-(2'-chloroethoxy)ethanol, 6.5 parts of zinc chloride and 10.0 parts of chloroacetic acid were added to the same reactor as in Example 2, followed by stirring and heating. After that, 1
Reduce the pressure inside the system to 100mm/l1g at 00℃,
Hydrogen chloride gas was quickly introduced at a rate of 60 parts/llr, and after the reaction pressure was brought to normal pressure, the maximum pressure was 3.0 kg/aJ-
In order to become a G, we will continue to introduce all:! It took 7 hours to introduce 1150 parts of hydrogen chloride gas.

The reaction solution was analyzed in the same manner as in Example 1.

The conversion rate of 2-(2'-chloroethoxy)ethanol is 4
6.8%.

The selectivity of di(2-chloroethyl)ether is 62.8%
, the selectivity for engineered ethylene chlorohydrin was 25.4%, and the selectivity for ethylene glycol was 0.2%.

Examples 5-8 Diethylene glycol 106 in a reactor similar to Example I
The reaction was carried out under the conditions shown in Table 2, and the obtained results are shown in Table 2.

[Effects of the Invention] Using the method of the present invention, even if a chlorinated ether containing a hydroxyl group is chlorinated with hydrogen chloride, the main chain of the ether is less likely to be cleaved, and therefore the by-products that are hot to separate from the ether are reduced. The production of the ether is reduced, and the ether with high purity can be obtained in good yield.

Claims (1)

[Claims] 1. RCH_2CH_2OCH_2CH_2OH_---[
I ] [Here, R represents a hydroxyl group or a chlorine atom. ] The following general formula [II] RCH_2CH_2OCH_2CH_2Cl --- [I
I] [Here R is the same as above. ] A method for producing a chlorinated ether compound shown in 2. The carboxylic acid to be present is an aliphatic mono- or polycarboxylic acid having 1 to 15 carbon atoms, an alicyclic mono- or polycarboxylic acid having 6 to 15 carbon atoms, or an aromatic mono- or polycarboxylic acid having 7 to 15 carbon atoms. and one or more carboxylic acids selected from the group consisting of mono- or polycarboxylic acids having a heterocycle. 3. The method according to claim 1 or 2, wherein the amount of carboxylic acid present is 0.1 to 10% by weight based on the compound represented by the general formula [I].