JP3353937B2 - Method for producing chloromethyl alkyl ether - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to paraformaldehyde (CH 2 _{O) n} added to the alcohol, by blowing hydrogen chloride, a method for producing the chloromethyl alkyl ether.

[0002]

2. Description of the Related Art Many processes for producing chloromethyl alkyl ethers (particularly chloromethyl methyl ether) have already been reported. Typical is US Pat. No. 2,666,761.
As shown in No. 6, this is a method in which a mixture of paraformaldehyde and an alcohol (particularly methanol) is treated with hydrogen chloride. A similar general method is described in US Pat.
Nos. 432 and 2681839, in which calcium chloride is added to the reaction vessel to form a solution with the coproduct water.

Further, in US Pat. No. 3,780,777, as an improved method, alcohol (particularly methanol) is saturated with hydrogen chloride, paraformaldehyde is added thereto together with sufficient hydrogen chloride at a temperature of 15 ° C. or less, and the reaction mixture is treated with chloromethyl alkyl ether. Has been collected.

However, in these methods, when a reaction such as etherification of chloromethyl alkyl ether is carried out, a considerable amount of chloromethylalkoxymethyl ether, which causes a serious by-product, is formed. For this reason, the recovered chloromethyl alkyl ether required further purification steps such as distillation.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the disadvantageous phenomena of the above-mentioned method, to improve the purity of the recovered chloromethyl alkyl ether, to omit the purification step, and to reduce the cost. To improve it.

[0006]

The present invention provides a compound of the general formula (I)

[0007]

Embedded image

Wherein R represents alkyl, alkoxyalkyl, halogenated alkyl, phenyl, substituted phenyl, benzyl or substituted benzyl, to which paraformaldehyde (CH ₂ O) _n is added;
Formula (II) is obtained by blowing hydrogen chloride.

[0009]

Embedded image

(Wherein R represents alkyl, alkoxyalkyl, alkyl halide, phenyl, substituted phenyl, benzyl or substituted benzyl) is a reaction by-product formed in the production of the chloromethylalkyl ether represented by the formula: General formula (III)

[0011]

Embedded image (Wherein R represents alkyl, alkoxyalkyl, alkyl halide, phenyl, substituted phenyl, benzyl or substituted benzyl), a chloromethylalkyl after recovering the ether, times
General formula (II) characterized in that hydrogen chloride is further blown into the collected chloromethyl alkyl ether.
Is a method for producing a chloromethyl alkyl ether represented by the formula:

In the process according to the invention, the reaction scheme

[0013]

(Equation 1)

Thus, paraformaldehyde is added to the alcohol represented by the general formula (I) , and sufficient hydrogen chloride is blown into the alcohol to form a chloride represented by the general formula (II). This gives a romethylalkyl ether.

At this time, it is desirable to use 1.0 to 1.2 equivalents of the alcohol represented by the general formula (I) with respect to paraformaldehyde, and after adding paraformaldehyde, the reaction proceeds at 10 ° C. or less. It is desirable to make it.
Furthermore, it is desirable that the alcohol represented by the general formula (I) is saturated with hydrogen chloride in advance. This facilitates the subsequent addition of paraformaldehyde and temperature control during the reaction.

At the beginning of the reaction, only a single phase exists,
As the reaction proceeds, the product represented by the general formula (II)
The resulting chloromethyl alkyl ether phase separates as a light upper phase. The heavy lower phase is mostly a mixture of water, alcohol, and HCl. Among the chloromethyl alkyl ethers represented by the general formula (II) recovered by the phase separation, chloromethylalkoxymethyl ether represented by the general formula (III) as a by- product It is present at 1-3% relative to the alkyl ether.

In the present invention, in order to reduce the content of the chloromethylalkoxymethyl ether represented by the general formula (III) , the recovered chloromethylalkyl ether represented by the general formula (II) is reduced. Blow more hydrogen chloride inside,
Thereafter, a step of backing with nitrogen was added to remove excess acid. The production process of the present invention is based on the reaction formula [number
2].

[0018]

(Equation 2)

Reaction Formula [Equation 2] As represented by Formula B,
Chloromethylalkoxymethyl ether is the target
It becomes chloromethyl alkyl ether, and is further raw in formula B
The resulting “CH ₂ O” is a reaction similar to the reaction formula [Formula 2] A formula.
Chloromethyl alkyl ether
Becomes As a result, the chloromethylalkoxymethyl ether represented by the general formula (III) is converted to the chloromethylalkoxymethyl ether represented by the general formula (II).
Against chloromethyl alkyl ethers, 0.5%
It became possible to reduce to the following. Moreover, the chloromethyl alkyl ether represented by the general formula (II), which is the target product, can be obtained in a yield of 90% or more.

In the general formula (II) obtained by this reaction ,
The chloromethyl alkyl ether represented by the formula (III), which is a serious by-product, has a low content of chloromethylalkoxymethyl ether represented by the general formula (III), so that derivatization such as etherification can be performed without further purification. It can be directly used for the reaction.

If the distillation step, which is the most common purification method, is added, the yield of the compound of the present invention is reduced, so that the cost reduction effect brought about by the omission of the purification step according to the present invention is enormous. .

[0022] Although in order to remove impurities is generally performed the separation of impurities, the present invention is an extension of the reaction steps, by reaction steps similar to operation, the desired product impurities produced in the reaction step Is an epoch-making thing.

A chloromethylalkyl ether represented by the general formula (II), a chloromethylalkoxymethyl ether represented by the general formula (III) and a chloromethylalkoxymethyl ether represented by the general formula (I)
Alcohols that are a phase of the recovered chloromethyl alkyl ether is reacted with sodium alkoxide or phenoxide, sodium, to form a more stable derivative,
It can be analyzed by gas chromatography.

[0024]

The present invention will be described below in more detail with reference to examples.

Example 1 Synthesis of Chloromethyl Ethyl Ether Hydrogen chloride was blown into 280.3 ml (4.8 mol) of ethanol until saturation was reached. 120.1 g (4.0 mol) of formaldehyde are charged all at once. Thereafter, hydrogen chloride was blown in continuously, and 218.8 g of hydrogen chloride was added.
At the time of blowing (6.0 mol), chloromethyl ethyl ether is obtained as the upper phase. Chloromethylethoxymethyl ether, a by-product at this time, was 1.70% of chloromethylethyl ether. After separating this reaction solution, 18.2 g (0.5 mol) of hydrogen chloride was further blown into the obtained chloromethylethyl ether phase, and then nitrogen backing was performed to obtain 348.3 g of chloromethylethylether. Obtained in a yield of 92.1% based on paraformaldehyde. At this time, by-product chloromethylethoxymethyl ether was 0.45% with respect to chloromethylethyl ether.

[0026]

The chloromethyl alkyl ether obtained by this reaction has a low concentration of chloromethylalkoxymethyl ether, and can be subjected to a derivatization reaction such as etherification without further purification such as distillation. Can be used directly. Therefore, the yield is high,
Since the distillation step can be omitted, the effect on economic efficiency is enormous.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-203927 (JP, A) JP-A-50-47914 (JP, A) JP-A-56-65838 (JP, A) 2661 (JP, B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) C07C 41/01 C07C 43/12 C07C 43/174 C07C 43/225

Claims (2)

(57) [Claims] 1. A compound of the general formula (I) (Wherein R represents alkyl, alkoxyalkyl, halogenated alkyl, phenyl, substituted phenyl, benzyl or substituted benzyl), paraformaldehyde (CH ₂ O) _n is added to the alcohol, and hydrogen chloride is blown into the alcohol. By the general formula (II) (Wherein, R represents alkyl, alkoxyalkyl, alkyl halide, phenyl, substituted phenyl, benzyl or substituted benzyl), and is a reaction by-product of the general formula ( III) (Wherein R represents alkyl, alkoxyalkyl, alkyl halide, phenyl, substituted phenyl, benzyl or substituted benzyl), a chloromethylalkyl after recovering the ether, times
General formula (II) characterized in that hydrogen chloride is further blown into the collected chloromethyl alkyl ether.
A method for producing a chloromethyl alkyl ether represented by the formula: 2. The recovered chloromethylalkyl
After further blowing hydrogen chloride into
Nitrogen back to remove excess acid
The general method according to claim 1, wherein a step is added.
Preparation of chloromethyl alkyl ether represented by formula (II)
Construction method.