JPH0977762A - Production of 1-allyloxymethyl-1,4-dioxane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce the subject compound useful as a basic raw material for hydrophilic silicone resins in high yield while suppressing the production of byproduct by carrying out the reaction in the presence of a specific silicon compound. SOLUTION: The objective compound is produced by contacting (A) ethylene chlorohydrin with (B) allyl glycidyl ether in the presence of (C) stannic chloride catalyst and subjecting the reaction product to intramolecular cyclization reaction by using (D) a dehydrochlorination agent (e.g. NaOH). Each of the above reactions is carried out in the presence of (E) a silicon compound having at least one SiO bond in the molecule (preferably having <=2 reactive groups in the molecule). Preferably, the component E is one or more kinds of compound of formula (R is H or a 1-4C alkyl; R<1> is methyl, phenyl, vinyl or 3,3,3- trifluoropropyl; (x) is 0 or 1-3; (y) is 3-6; (m) is 0-100) and the amount of the component E is 0.01-1,000 times weight of the component D.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has an extremely high yield of 99% or more of 2-allyloxymethyl-1,4-dioxane, which has an unsaturated bond and a dioxane skeleton in the molecule and exhibits hydrophilicity. It is about how to get in. This 2
-Allyloxymethyl-1,4-dioxane easily reacts with S in siloxane using a platinum-based or rhodium-based catalyst.
Since it undergoes a hydrosilation reaction with iH to form the group shown below, it can be used as a basic raw material for a hydrophilic silicone resin.

[0002]

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[0003]

2. Description of the Related Art
As a method for synthesizing 2-allyloxymethyl-1,4-dioxane, the following production method (Russian document Khim.
Geterotsikl. Sodein, No. 2, 1973, pp. 161-163).

[0004]

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According to the above methods (1) and (2), allyl glycidyl ether can be produced in a larger amount and cost less than chloroethyl glycidyl ether.
The method (2) is industrially advantageous.

However, 2-allyloxymethyl-1,4-
In the industrially advantageous method (2) for producing dioxane, stannic chloride used as a catalyst has an effect of promoting the reaction, but it is produced as an intermediate because of its easiness of ionization. -In order to polymerize the allyloxy group of allyloxy-3- (2-chloroethoxy) -2-propanol, a large amount of a high molecular weight by-product represented by the following formula (i) is produced, resulting in the desired 2 -The drawback is that the yield of allyloxymethyl-1,4-dioxane is limited to 70% even at the highest value.

[0007]

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[0008] The present invention has been made in view of the above circumstances,
The by-product of the polymer of the above formula (i) is reduced, and 2-
An object is to provide a method for producing allyloxymethyl-1,4-dioxane.

[0009]

Means for Solving the Problems and Embodiments of the Invention In order to achieve the above-mentioned object, the inventors of the present invention described above in (2).
As a result of earnestly researching a method for reducing a high molecular weight by-product produced by the method described above, that is, a polymer of the above formula (i), it was found that at least 1 part of stannic chloride in the molecule was lost.
When a silicon compound having one SiO bond is coexistent, the SiO bond-containing silicon compound does not impair the activity of stannic chloride serving as a catalyst, and suppresses the formation of a by-product polymer, and further 1-allyloxy Even when the 3- (2-chloroethoxy) -2-propanol is subjected to an intramolecular cyclization reaction using a dehydrochlorinating agent, coexistence of the SiO bond-containing silicon compound similarly produces a by-product polymer. The target 2-allyloxymethyl-1,
The present inventors have found that 4-dioxane can be obtained in high yield, and have completed the present invention. Although the mechanism of suppressing the by-product polymer is not clearly understood, SiO
It is presumed that Sn bond was partially generated and this was effective.

Therefore, according to the present invention, ethylene chlorohydrin and allyl glycidyl ether are contacted and reacted in the presence of a stannic chloride catalyst, and then an intramolecular cyclization reaction is caused using a dehydrochlorination agent. 2-allyloxymethyl-
In the method for producing 1,4-dioxane, coexistence of a silicon compound having at least one SiO bond in the molecule during the reaction between ethylene chlorohydrin and allyl glycidyl ether and the intramolecular cyclization reaction. Provided is a method for producing 2-allyloxymethyl-1,4-dioxane.

The present invention will be described in more detail below. The method for producing 2-allyloxymethyl-1,4-dioxane according to the present invention is carried out in the presence of a stannic chloride catalyst as shown in the following reaction formula A. Allyl glycidyl ether and ethylene chlorohydrin are reacted to synthesize 1-allyloxy-3- (2-chloroethoxy) -2-propanol, and then 1-allyloxy-3- (2 2-chloromethyl) -1,4-dioxane is synthesized by dehydrochlorination reaction of -chloroethoxy) -2-propanol, and in this case, at least in the molecule in the reaction system of these reaction formulas A and B. The reaction is carried out in the presence of a silicon compound having one SiO bond (hereinafter referred to as a SiO compound).

[0012]

[Chemical 6]

The above reaction will be described in detail below. [I] Synthesis of 1-allyloxy-3- (2-chloroethoxy) -2-propanol by reaction of allyl glycidyl ether and ethylene chlorohydrin (Scheme A) This reaction may or may not utilize a solvent. May be. Since the use of a solvent lowers the pot yield of the product, it is better to carry out the reaction in a solvent-free system. In addition, in this reaction, a solution of ethylene chlorohydrin, stannic chloride as a catalyst, and a SiO compound was added to a solution at a temperature of 2
It is preferable to add and react allyl glycidyl ether at 0 to 130 ° C. The reaction time is usually 1 to 3 hours.

The reaction proceeds as in the above formula A, but the ethylene chlorohydrin used in this case is equimolar to 100 times by mole, preferably 1.
It is preferable to use it in a molar amount of 01 to 30 times.

The amount of stannic chloride used as a catalyst is 0.001 to 0.001 by weight based on allyl glycidyl ether.
It is 0.1 times, preferably 0.005 to 0.05 times.

In this reaction, it is necessary to carry out the reaction in the presence of a SiO compound. In this case, the addition amount of the SiO compound is 0.01 to 1000 times by weight, and particularly 0.1% by weight with respect to the stannic chloride, in order to effectively suppress the production of the above-mentioned high amount of the polymer (i). It is preferably from 05 to 100 times. The SiO compound may be used by dissolving it in ethylene chlorohydrin, by dissolving it in stannic chloride as a catalyst, or by dissolving it in allyl glycidyl ether.

The SiO compound is not particularly limited as long as it has a SiO bond, and may be in the form of oil, resin, or raw rubber. After completion of the reaction, the product is distilled or the SiO bond-containing silicon compound is used. From the standpoint of removal, it is preferable that the number of reactive groups such as hydrolyzable groups is 2 or less in one molecule. The following can be illustrated as these compounds.

[0018]

[Chemical 7]

[0019]

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[0020]

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[0021]

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[0022]

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[0023]

[Chemical 12]

[0024]

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When the reaction is carried out in the coexistence of the stannic chloride catalyst and the SiO compound, the side reaction is close to zero, and 1-allyloxy-3- (2-chloroethoxy) -2 is quantitatively obtained.
-Since propanol is obtained, it is not necessary to take out this 2-propanol intermediate after the reaction, separate and purify it,
It is advisable to distill off only an excessive amount of ethylene chlorohydrin under reduced pressure and send it to the next dehydrochlorination reaction.

[II] Synthesis of 2-allyloxymethyl-1,4-dioxane by dehydrochlorination reaction of 1-allyloxy-3- (2-chloroethoxy) -2-propanol (Scheme B) Although a solvent may or may not be used, it is usually a good idea to use a solvent because the dehydrochlorination agent solidifies as the reaction proceeds. Solvents that can be used include chain ethers such as diethyl ether and dibutyl ether, cyclic ethers such as tetrahydrofuran and dioxane, aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene and xylene. There is.

Examples of the dehydrochlorination agent include organic amines such as triethylamine and pyridine, and NaOH and LiO.
Alkali metal hydroxides such as H, KOH, Ca (OH) ₂ and Mg (OH) ₂ can be used. Of these, NaOH is industrially inexpensive and easy to handle.

The amount of the dehydrochlorination agent used depends on the HCl generated.
The molar ratio is 1 to 10 times, but preferably 1.01 to 2 times the molar ratio.

This reaction also requires the coexistence of the above-mentioned SiO compound, and the amount thereof is 0.01 to 1000 times by weight ratio with respect to the stannic chloride used in the reaction step [I].
It is preferably 0.05 to 100 times. When the silicon compound is distilled off in the reaction step [I], it may be supplemented, but it is usually difficult to distill off the silicon compound, and therefore it is not necessary to add it.

In this reaction, this reaction is carried out by mixing the dehydrochlorinating agent and the solvent and adding the product obtained in the step [I] dropwise to the mixture which is heated under reflux. .

The reaction temperature depends on the boiling point of the solvent used, but is usually 30 to 200 ° C. The reaction time is usually 10 minutes to 20 hours, preferably 30 minutes to 7 hours.

The obtained crude 2-allyloxymethyl-1,4
-Dioxane can be purified by washing with water to remove the product of the dehydrochlorinating agent and HCl, then by distillation.

[0033]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Example 1 Ethylene chlorohydrin 16
14.1 g (1.0 mol) of allyl glycidyl ether containing 30 g of diphenyldimethoxysilane was added to a mixed solution of 10.2 g (20.0 mol) and 2.0 g of stannic chloride at 35 to 40 ° C. The mixture was added dropwise over a period of time, kept at the same temperature, and aged for 2 hours.

Excessive ethylene chlorohydrin was distilled off under reduced pressure, and the residue was analyzed to find that 1-allyloxy-3- (2-chloroethoxy) -2-propanol was quantitatively produced. confirmed. 1 more to this concentrated residue
g of diphenyldimethoxysilane was added (this is abbreviated as liquid A).

60 g (1.5 mol) of sodium hydroxide and 200 g of diethyl ether were mixed and heated to reflux.
Liquid A was added dropwise to this mixture over 1 hour to cause a reaction.
Further, it was aged at the reflux temperature for 5 hours.

After the liquid after aging was cooled to room temperature, 200 g of water was added and well stirred. After stirring, the aqueous layer was extracted twice with 50 g of diethyl ether, and this was combined with the organic layer that was the upper layer of the original liquid separation, and then the combined organic layer was combined with 5
% Aqueous acetic acid solution (50 g). After distilling off the diethyl ether, it was distilled under reduced pressure to give 2-allyloxymethyl-1,4-dioxane 157.3 g (boiling point 90 ° C./yield 99.4%).
15 mmHg) was obtained. The analytical values of the obtained compound are shown below. Specific gravity and refractive index d ²⁰ ₄ 1.029 η ²⁰ _D 1.4510 Infrared absorption spectrum (see FIG. 1) Specific absorption C = C 1719 cm ⁻¹ C—O—C 1110 cm ⁻¹

[Example 2] The same operation as in Example 1 was carried out except that diphenylsilanediol was used as the silicon compound, and 2-allyloxymethyl-1,4 was obtained in a yield of 99.2%. -Dioxane was obtained.

[Example 3] Silicon compounds of 1, 1, 3,
A similar operation was performed under the same conditions as in Example 1 except that 3,5,5,7,7-octamethylcyclotetrasiloxane was used, and 2-allyloxymethyl-1,2 was obtained in a yield of 99.0%. 4-dioxane was obtained.

Example 4 A similar operation was performed under the same conditions as in Example 1 except that the trimethylsilyl-capped dimethylpolysiloxane shown below was used instead of the silicon compound.
2-Aryloxymethyl-1,4-dioxane was obtained with a yield of 99.3%.

[0041]

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[Example 5] The same operation as in Example 1 was carried out except that KOH was used as the dehydrochlorination agent. 2-allyloxymethyl-1,4 was obtained in a yield of 99.1%. −
Dioxane was obtained.

[Example 6] The same operation as in Example 1 was carried out except that toluene was used instead of diethyl ether as a solvent, and 2-allyloxymethyl-1,4 was obtained in a yield of 99.0%. -Dioxane was obtained.

Example 7 The amount of ethylene chlorohydrin used was reduced to 1610.2 g (20.0 mol) to give 24
A similar operation was performed under the same conditions as in Example 1 except that 1.5 g (3.0 mol) was used, and the yield was 99.0% and 2
-Allyloxymethyl-1,4-dioxane was obtained.

Comparative Example When the same operation as in Example 1 was carried out except that no silicon compound was used, a high molecular weight by-product polymer was produced, and 2-allyloxymethyl-1,4-dioxane was produced. The yield was low at 69.9%.

[Reference Example] The catalyst was changed from stannic chloride to BF ₃ ·.
When a similar operation was performed under the same conditions as in Example 1 except that a saturated diethyl ether solution was used, the yield of 2-allyloxymethyl-1,4-dioxane was as low as 70.0%, and BF It was confirmed that the silicon compound was not effective in the reaction using the ₃ -diethyl ether solution catalyst.

[0047]

INDUSTRIAL APPLICABILITY According to the present invention, 2-allyloxymethyl-1,4-dioxane can be produced in a high yield while suppressing the formation of by-products.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of 2-allyloxymethyl-1,4-dioxane.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaharu Takahashi, No. 1 Hitomi, Osamu Matsuida-cho, Usui-gun, Gunma Prefecture Inside the Silicon Electronic Materials Research Laboratory, Shin-Etsu Chemical Co., Ltd. (72) Minoru Igarashi Matsuida-cho, Usui-gun, Gunma Prefecture Hitomi 1 No. 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (72) Inventor Takashi Hirai 1096 Toda, Atsugi City, Kanagawa Prefecture Nakatomi 201 (72) Tadashi Banno 26 Takamura, Hiratsuka City, Kanagawa Prefecture 38 Takamura housing complex −101 (72) Inventor Masayuki Umeno 521-3 Chigasaki, Chigasaki City, Kanagawa Prefecture

Claims (5)

[Claims] 1. Ethylene chlorohydrin and allyl glycidyl ether are contacted and reacted in the presence of a stannic chloride catalyst, and then an intramolecular cyclization reaction is caused by using a dehydrochlorination agent to give 2 -In the method for producing allyloxymethyl-1,4-dioxane, at least one SiO in the molecule during the reaction between ethylene chlorohydrin and allyl glycidyl ether and the intramolecular cyclization reaction, respectively.
A method for producing 2-allyloxymethyl-1,4-dioxane, which comprises allowing a silicon compound having a bond to coexist. 2. The method according to claim 1, wherein the silicon compound has two or less reactive groups in the molecule. 3. The method according to claim 1, wherein the silicon compound is one or more compounds represented by the following general formula. Embedded image (Wherein, R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R ^{1 s} may be the same or different from each other and may be a methyl group, a phenyl group, a vinyl group or a 3,3,3-trifluoropropyl group, x is 0, 1, 2 or 3, and y is 3, 4, 5 or 6 , M is an integer of 0 to 100. ) 4. The method according to claim 3, wherein the silicon compound is one kind or two or more kinds of the compounds shown below. Embedded image (In the formula, m is an integer of 0 to 100.) 5. The production method according to claim 1, wherein the content of the silicon compound is 0.01 to 1000 times the weight ratio of stannic chloride.