JPH07215979A - Method for producing spiroglycol - Google Patents

Abstract

PURPOSE:To produce 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro [5.5]undecane in improved purity and yield and in a reduced amount of wasted water by reacting pentaerythritol with hydroxypivalaldehyde. CONSTITUTION:Pentaerythritol is reacted with hydroxypivalaldehyde in an organic solvent such as xylene or toluene at a temperature of 40-80 deg.C to obtain the objective compound. For example, the mixture of the pentaerythritol with the organic solvent is heated to a temperature of 40-80 deg.C and subsequently dropwisely mixed with the aqueous solution of the hydroxypivalaldehyde and the aqueous solution of an acid catalyst. The mixture is subjected to the reaction for several hrs in the temperature of the range, and subsequently the obtained slurry-like mixture is filtered, washed and dried to obtain the objective compound.

Description

Detailed Description of the Invention

[0001]

This invention relates to 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,1.
It relates to an improved process for the preparation of 0-tetraoxaspiro [5.5] undecane. 3,9-bis (2
-Hydroxy-1,1-dimethylethyl) -2,4
8,10-Tetraoxaspiro [5.5] undecane is β, β, β ′, β′-tetramethyl-in the industry.
It is also called 2,4,8,10-tetraoxaspiro [5.5] undecane-3,9-diethanol and has the following formula

[0002]

It has the chemical structure: In the present specification, this compound is hereinafter referred to as spiroglycol.

Spiroglycol is used as a synthetic intermediate for low molecular weight compounds such as urethane, ester, thiol and ether compounds, and as an intermediate for high molecular compounds such as polyurethane, polyester, polyether polyols and epoxy resins. As a raw material for synthetic lubricating oils, cross-linking agents, reactive diluents, plasticizers, adhesives, modifiers, antioxidants, light stabilizers, etc., as well as photocurability, chemical resistance, heat resistance, wear resistance, It is useful as a raw material for weather resistant and / or impact resistant resins.

[0005]

2. Description of the Related Art Spiroglycol is generally produced from pentaerythritol and hydroxypivalaldehyde as raw materials by an acetalization reaction of the following formula.

[0006]

The acetalization reaction is a reversible reaction, and water is by-produced during the reaction. Therefore, a method is known in which the reaction proceeds while removing water from the system. For example, US Pat. No. 2,945,008 describes a method for producing spiroglycol by azeotropic dehydration under reflux of toluene. Further, US Pat. No. 3,092,640 and Japanese Patent Application Laid-Open No. 64-61485 describe a method for producing spiroglycol using water as a solvent by utilizing the fact that spiroglycol is hardly soluble in water.

However, the method of carrying out the reaction under the reflux of toluene has a problem that the yield is low. On the other hand, the method using water as a solvent requires a large amount of cost in order to avoid environmental pollution, since a large amount of wastewater having a high environmental load is produced as a by-product. Further, there is a problem that the solubility of the side reaction product in water is low and the purity of the obtained product is low.

[0009]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems of the prior art and to provide a method for producing spiroglycol having improved yield, amount of waste water and product purity. . As a result of various studies, the inventors of the present invention have conducted various studies in order to develop a method for producing spiroglycol, which has a high yield and produces little wastewater with a high environmental load. On the other hand, it was found that the yield of spiroglycol is increased by carrying out the reaction at a specific temperature, and the present invention has been completed.

[0010]

That is, the present invention provides a method for producing spiroglycol by reacting pentaerythritol and hydroxypivalaldehyde in the presence of an organic solvent at a temperature in the range of 40 to 80 ° C. Is provided. A feature of the present invention is that the reaction is carried out at a temperature in the range of 40 to 80 ° C. using an organic solvent.

The organic solvent preferably used in the present invention includes aromatic hydrocarbons and aliphatic hydrocarbons, each of which may have a substituent such as halogen. Specific examples of the aromatic hydrocarbon are xylene, toluene, ethylbenzene, monochlorobenzene and the like, and specific examples of the aliphatic hydrocarbon are hexane, heptane, octane and the like. Among these, xylene or toluene is particularly preferable as the aromatic hydrocarbon solvent, and hexane or heptane is particularly preferable as the aliphatic hydrocarbon solvent. These organic solvents may be used alone or in admixture of two or more. When an oxygen-containing solvent, particularly an alcohol solvent such as methanol, ethanol, or isopropanol, or a ketone solvent such as acetone or methyl ethyl ketone is used, a side reaction product is likely to be formed, and the yield is lowered. Not preferable.

The reaction of the present invention is carried out at a temperature lower than the boiling point of the organic solvent used, generally in the range of 40 to 80 ° C, preferably 50 to 70 ° C. If the temperature is lower than 40 ° C., the reaction rate becomes slow, so that it is not industrial and the yield and purity of spiroglycol are lowered. If the reaction temperature exceeds 80 ° C, side reaction products increase, which is not preferable.

The amount of organic solvent used in the reaction is
The produced spiroglycol has a slurry concentration of 10 to 50
It is preferable to adjust it so that the content is wt%. If the slurry concentration is higher than 50% by weight, scaling occurs and the yield is lowered, and if it is lower than 10% by weight, the productivity per volume is lowered, which is not preferable.

The spiroglycol-forming reaction of the present invention is an acetalization reaction of pentaerythritol and hydroxypivalaldehyde according to the above reaction formula, and is accompanied by water as a by-product, but water is present in the reaction system together with the organic solvent. It doesn't matter. In addition to water by-produced by the reaction, the presence of water from the beginning of the reaction is also allowed. In any case, as described above, it is preferable to adjust the amounts of the organic solvent and water so that the slurry concentration of the produced spiroglycol becomes 10 to 50% by weight. The amount of water present in the reaction system is 3 with respect to the amount of the organic solvent, including water produced as a by-product.
Up to about twice the weight is acceptable. Preferably, the amount of water including by-produced water is adjusted to 2 times or less, more preferably 1 times or less, of the amount of the organic solvent.

This spiroglycol-forming reaction is usually carried out in the presence of an acid catalyst. There is no particular limitation on the acid catalyst used, but generally, a mineral acid such as sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, or an organic acid such as p-toluenesulfonic acid or methanesulfonic acid can be used. The preferable amount of the acid catalyst used varies depending on the type of the acid catalyst, but may be any amount as long as it can acidify the system, and is generally 1 to 60 mol%, preferably 3 to 3 with respect to the charged amount of pentaerythritol.
It is selected from the range of 30 mol%. The acid catalyst may be used alone or in combination of two or more.

There is no particular limitation on the reaction method of pentaerythritol and hydroxypivalaldehyde, but the following method can be used, for example.

(1) A mixture of pentaerythritol, hydroxypivalaldehyde, an organic solvent and an acid catalyst,
A method in which the reaction is carried out by heating to a predetermined reaction temperature, (2) A hydroxypivalaldehyde aqueous solution and an acid catalyst are continuously added to a mixture of pentaerythritol and an organic solvent which has been preliminarily kept at a temperature similar to the reaction temperature. (3) A method in which a hydroxypivalaldehyde aqueous solution is continuously added to a mixture of pentaerythritol, an acid catalyst and an organic solvent, which has been preliminarily kept at a temperature similar to the reaction temperature. Or a method of carrying out the reaction while intermittently adding, (4) in a mixture of hydroxypivalaldehyde and an organic solvent which has been preliminarily brought to a temperature similar to the reaction temperature,
A method of carrying out the reaction while continuously or intermittently pouring an aqueous solution of pentaerythritol and an acid catalyst, (5) in a mixture of hydroxypivalaldehyde and an organic solvent which has been preliminarily kept at a temperature similar to the reaction temperature. , A method of carrying out the reaction while continuously or intermittently adding an acidic aqueous solution in which pentaerythritol and an acid catalyst are mixed.

The amount of pentaerythritol charged is preferably in the range of 0.3 to 0.6 mol, and more preferably in the range of 0.4 to 0.5 mol, based on 1 mol of hydroxypivalaldehyde. When it deviates from this range, side reaction products tend to increase.

The hydroxypivalaldehyde used in the reaction with pentaerythritol may, of course, be a purified product or a reaction mixture obtained by synthesis. Hydroxypivalaldehyde can be produced, for example, by reacting formaldehyde with isobutyraldehyde in the presence of a basic catalyst, and the reaction mixture thus obtained can be used as it is for the reaction with pentaerythritol. When this reaction mixture is used, it contains a basic catalyst, and therefore, an acidic catalyst is usually used in an amount sufficient to neutralize the basic catalyst and further acidify the reaction system. Of course, the means for producing hydroxypivalaldehyde is not limited in the present invention.

The reaction time between pentaerythritol and hydroxypivalaldehyde is usually preferably about 3 to 24 hours, including the addition time when one raw material is continuously or intermittently added to the other raw material. , And more preferably about 5 to 15 hours. After the completion of the reaction, a slurry-like mixture containing spiroglycol is obtained, so that the desired spiroglycol can be isolated by solid-liquid separation, and if necessary, washing and drying.

[0021]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. In the following,% and parts mean% by weight and parts by weight, respectively, unless otherwise specified.

Production Example (Synthesis of Hydroxypivalaldehyde) A mixture of 56 parts of isobutyraldehyde and 3.1 parts of triethylamine was heated to 60 ° C. and 66 parts of 35% formalin was added dropwise over 4 hours. Then, while maintaining the temperature, the mixture was stirred for 4 hours to remove 6 parts of hydroxypivalaldehyde.
124 parts of an aldol reaction solution containing 0.5% was obtained.

Example 1 50 parts of pentaerythritol was suspended in 311 parts of xylene and heated to 60 ° C. Thereto, about 2 parts of 124 parts of the aldol reaction solution containing 60.5% of the hydroxypivalaldehyde obtained in the above Production Example and 15 parts of 25% nitric acid were added.
It was co-injected over time. After that, while maintaining that temperature,
The combined injection time was also stirred for 10 hours. The resulting slurry mixture was filtered to give 100 parts of water and 100 parts of xylene.
After washing with 1 part, it was dried to obtain 100 parts of spiroglycol (yield 89.5%, product purity 99.5%). At this time, 175 parts of waste water was by-produced.

Example 2 A reaction was conducted in the same manner as in Example 1 except that 306 parts of toluene was used instead of 311 parts of xylene. The resulting slurry mixture was filtered to obtain 100 parts of water and 10 parts of toluene.
It was washed with 0 part and dried to obtain 99 parts of spiroglycol (yield 88.6%, product purity 99.5%). At this time, 175 parts of waste water was by-produced.

Example 3 A reaction was carried out in the same manner as in Example 1 except that 233 parts of hexane was used instead of 311 parts of xylene. The resulting slurry mixture was filtered to obtain 100 parts of water and 10 parts of hexane.
After washing with 0 part and drying, 97 parts of spiroglycol were obtained (yield 86.8%, product purity 97.5%). At this time, 177 parts of waste water was by-produced.

Comparative Example 1 Pentaerythritol (50 parts) was suspended in water (433 parts), heated to 60 ° C., and completely dissolved. 60.5% of the hydroxypivalaldehyde obtained in the above Production Example was added thereto.
Aldol reaction solution containing 124 parts, and 60% nitric acid 9.5
Parts were co-injected over about 5 hours. Then, while maintaining that temperature, the mixture was stirred for 9 hours including the combined injection time. The resulting slurry mixture was filtered, washed with 300 parts of water and dried to obtain 98 parts of spiroglycol (yield 8
7.7%, product purity 96.5%). At this time, 800 parts of waste water was by-produced.

Comparative Example 2 The hydroxypivalaldehyde obtained in the above Production Example was mixed with 6
124 parts of an aldol reaction solution containing 0.5%, 50 parts of pentaerythritol, 1.5 parts of p-toluenesulfonic acid and 295 parts of toluene were mixed, and heated and stirred under reflux for 2.5 hours. Water generated during the reaction was removed by azeotropic dehydration. After completion of the reaction, the mixture was cooled to room temperature, the obtained slurry mixture was filtered, washed with 100 parts of water and 100 parts of toluene and then dried to obtain 85 parts of spiroglycol (yield: 76.0%, Product purity 99.5%). At this time, 1
Sixty parts of waste water was by-produced.

The reaction conditions and results in the above Examples and Comparative Examples are summarized in Table 1.

[0029]

[Table 1]

[0030]

According to the present invention, the reaction of pentaerythritol and hydroxypivalaldehyde is carried out in the presence of an organic solvent at a temperature in the range of 40 to 80 ° C.
High-purity spiroglycol can be obtained with a high yield and without discharging a large amount of wastewater having a high environmental load.
Particularly, as compared with the case where water is used as the solvent (Comparative Example 1), the product purity is improved and the amount of waste water is reduced. Further, as compared with the case where the reaction is carried out under toluene reflux (Comparative Example 2), a high yield is achieved while maintaining a high product purity. Therefore, according to the present invention, spiroglycol can be obtained with high yield, high purity, and small amount of waste water.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masato Sekiguchi 5-1 Sokai-cho, Niihama-shi, Ehime Sumitomo Chemical Co., Ltd. (72) Manji Sasaki 3-1-1 Kasuga, Konohana-ku, Osaka No. 98 Sumitomo Chemical Co., Ltd.

Claims (7)

[Claims] 1. Pentaerythritol and hydroxypivalaldehyde are reacted in the presence of an organic solvent at a temperature in the range of 40 to 80 ° C., which is 3,9-bis (2-hydroxy-1,1). -Dimethylethyl) -2,
Process for producing 4,8,10-tetraoxaspiro [5.5] undecane. 2. The method according to claim 1, wherein the organic solvent is an aromatic or aliphatic hydrocarbon which may contain halogen in the molecule. 3. The method according to claim 2, wherein the organic solvent is an aromatic hydrocarbon selected from xylene and toluene. 4. The method according to claim 2, wherein the organic solvent is an aliphatic hydrocarbon selected from hexane and heptane. 5. The reaction is carried out at a temperature of 50 to 70 ° C.
The method according to any one of to 4. 6. The produced 3,9-bis (2-hydroxy-)
The slurry concentration of 1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro [5.5] undecane was
The method according to claim 1, wherein the amount of the organic solvent is selected so as to be 10 to 50% by weight. 7. The method according to claim 1, wherein the reaction is carried out in the presence of an acid catalyst.
The method described in any one of.