JP2001151718A - Method for producing tertiary butoxybenzene derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a tertiary butoxybenzene derivative by reacting a phenol compound with isobutylene in the presence of an acid catalyst, by which the unreacted isobutylene can quantitatively and efficiently be removed, recovered from the reaction solution and recycled. SOLUTION: This method for producing the tertiary butoxybenzene derivative by reacting a phenol compound with isobutylene in the presence of an acid catalyst, comprises (1) quantitatively dropping the reaction solution on a hot alkali aqueous solution to remove the unreacted raw materials and then distilling the residue to obtain the tertiary butoxybenzene derivative, or (2) quantitatively dropping the alkali-treated reaction solution on a heating medium to remove the unreacted raw materials and then distillingthe residue to obtain the tertiary butoxybenzene derivative.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a tertiary-butoxybenzene derivative useful as an intermediate material for medicinal and agricultural chemicals and functional materials.

[0002]

2. Description of the Related Art There have been proposed various methods for producing a tertiary-butoxybenzene derivative by reacting a phenol compound with isobutylene in the presence of an acid catalyst. Are also disclosed.

For example, in US Pat. No. 2,655,546, an aqueous sodium hydroxide solution is added to a reaction solution, unreacted phenol compounds are extracted and removed into an aqueous sodium hydroxide solution phase, and unreacted isobutylene in an organic phase is removed by heating. And a method for separating a tertiary-butoxybenzene derivative by distillation.

[0004]

Isobutylene is a gas that easily ignites at normal temperature and pressure and has a wide explosion range. From the viewpoint of safety, it is necessary to perform a stable treatment operation not only in the reaction but also in the removal and recovery operations. is there.

However, US Pat. No. 2,655,546
In the removal method described in the specification, unreacted isobutylene in a reaction solution is irregularly vaporized during an alkali addition treatment and a heat treatment of an organic phase due to heat of reaction between an unreacted phenol compound and an alkali. Released, stable removal,
Recovery becomes difficult and causes operational problems. Further, simply heating the organic phase results in inefficient removal of unreacted isobutylene and an increased proportion of the unreacted isobutylene remaining in the organic phase. When the tertiary-butoxybenzene derivative is separated by distillation, operations such as liquid foaming and isobutylene trapping are performed. In addition, it is extremely burdensome at the time of distillation, such as extension of the distillation time associated therewith. These are major problems in industrial-scale production.

The present invention has been made in view of the above problems, and an object of the present invention is to quantitatively and efficiently remove unreacted isobutylene from a reaction solution obtained by reacting a phenol compound with isobutylene in the presence of an acid catalyst. , Collecting and recycling methods.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the conventional problems, and as a result, a reaction solution obtained by reacting a phenol compound with isobutylene in the presence of an acid catalyst was obtained.
It has been found that unreacted isobutylene is quantitatively and efficiently released and removed to the gas phase by dropping a fixed amount into a hot alkali aqueous solution or by dropping a fixed amount into a heat medium after the alkali treatment, thereby completing the present invention. Was.

That is, the present invention provides a tertiary compound by reacting a phenol compound with isobutylene in the presence of an acid catalyst.
In the method for producing butoxybenzene, a tertiary-butoxybenzene derivative is obtained by removing the unreacted raw material by quantitatively dropping the reaction solution into a hot alkali aqueous solution and then obtaining a tertiary-butoxybenzene derivative by distillation. A method for producing a tertiary-butoxybenzene derivative, characterized in that a tertiary-butoxybenzene derivative is obtained by distillation after removing unreacted raw materials by quantitatively dropping a reaction solution subjected to an alkali treatment into a heating medium and then distilling the reaction solution. The way.

Hereinafter, the present invention will be described in detail.

The hot alkaline aqueous solution or heat medium used in the present invention is not particularly limited as long as unreacted isobutylene is released and removed in the gas phase, but is preferably maintained at 70 ° C. or higher. Are preferred. The heating medium is selected from hot water or a hot organic solvent. Examples of the organic solvent include saturated hydrocarbons such as heptane and octane, halogenated aliphatic hydrocarbons such as dichloroethane and trichloroethane, aromatic hydrocarbons such as benzene, toluene and xylene, and halogenated aromatics such as chlorobenzene and bromobenzene. Group hydrocarbons and the like can be used.

What is important in the present invention is to release unreacted isobutylene into the gas phase quantitatively and efficiently. As described above, it is difficult to release unreacted isobutylene into the gas phase quantitatively and efficiently by simply heating the reaction solution, and this can be achieved by dropwise addition of the reaction solution. The liquid temperature during the treatment is preferably higher as the unreacted isobutylene removal efficiency increases, but is limited by the reaction solvent used, the hot alkaline aqueous solution, and the heating medium. In order not to burden the distillation and separation of the tertiary-butoxybenzene derivative, the residual isobutylene of the organic phase after the treatment is preferably 0.1% by weight or less.
For this purpose, it is preferable that the temperature of the processing liquid is maintained at 70 ° C. or higher. Further, if the reaction solvent or the heat medium is in a reflux state during the treatment, unreacted isobutylene can be removed more efficiently.

The phenol compound used as a raw material of the tertiary-butoxybenzene derivative of the present invention includes phenol,
Cresol, chlorophenol, nitrophenol and the like are exemplified, and these are used for the reaction directly or after being dissolved in a solvent. The method of the present invention is particularly effective when producing tertiary-butoxychlorobenzene using para-chlorophenol as a raw material.

The solvent used in the present invention is usually
Saturated aliphatic hydrocarbons such as heptane and octane; halogenated aliphatic hydrocarbons such as dichloroethane and tri-chloroethane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated aromatics such as chlorobenzene and bromobenzene Selected from hydrocarbons. In the present invention, the boiling point of the solvent used is preferably as high as possible in order to efficiently remove unreacted isobutylene from the reaction solution. However, if it is too high, the distillation separation is burdensome. Considering the solubility of the raw material phenol compound, chlorobenzene and toluene are preferably used. Its usage is
The amount of the starting phenol compound to be dissolved at the set reaction temperature may be sufficient, but the higher the starting phenol compound concentration, the better. For example, when chlorobenzene is used, the concentration of the starting phenol compound is preferably from 40 to 70% by weight.

The acid catalyst used in the present invention is usually selected from aliphatic sulfonic acids such as sulfuric acid and methanesulfonic acid, and aromatic sulfonic acids such as paratoluenesulfonic acid. Particularly, sulfuric acid and methanesulfonic acid are used. It is preferably used. The amount used depends on the type of acid catalyst,
For example, in the case of methanesulfonic acid, it is selected from the range of 0.01 to 1 mol% based on the raw phenol compound,
In particular, 0.05 to 0.5 mol% is preferable.

The reaction temperature in the present invention is usually -10
The temperature is selected from the range of 0 ° C to 50 ° C, and 0 ° C to 30 ° C is particularly preferable.

The raw material isobutylene in the present invention is introduced into the solution in a gaseous or liquid state while stirring a phenol compound solution containing an acid catalyst, and reacted. The use amount thereof may be at least equimolar to the starting phenol compound, but if it is too small, the yield decreases, and if it is too large, it leaks out of the reaction system, and the amount of unreacted isobutylene to be removed is undesirably large. The preferred amount used in the present invention is 1.1 to 1.6 times the molar amount of the starting phenol compound.

Regarding the reaction time in the present invention, it is better to introduce the isobutylene in a short time as long as the reaction temperature can be controlled and the leak does not leak out of the reaction system. It is better to ripen for a long time after introduction.

This reaction is an equilibrium reaction, and a large amount of unreacted isobutylene and phenol compounds remain in the reaction solution obtained under the above reaction conditions and operations. It is possible to quantitatively and efficiently remove and recover unreacted raw materials.

When the method of the present invention is carried out using a hot alkaline aqueous solution, a vitreous processing tank cannot be used because the material of the processing tank is limited. A feature of the hot alkali aqueous solution treatment is that unreacted isobutylene and a phenol compound can be removed simultaneously. That is, unreacted isobutylene is released and removed in the gas phase, and the unreacted phenol compound becomes an alkali salt and is extracted and removed in the aqueous alkaline solution phase. Further, there is an advantage that the tertiary-butoxybenzene derivative can be directly separated by distillation from the organic phase separated after the treatment.

The alkali used when the method of the present invention is carried out with a hot alkaline aqueous solution is selected from sodium hydroxide and potassium hydroxide, but sodium hydroxide is preferably used from the viewpoint of economy and the like. The amount of the phenol compound to be used may be equal to or more than 1 mole of the unreacted phenol compound in the reaction solution, but is preferably equal to or more than 1.2 mole to remove the phenol compound with good reproducibility. The higher the concentration of the aqueous sodium hydroxide solution, the better, but if the concentration is too high, the aqueous solution phase contains the extracted sodium salt of the phenol compound. It precipitates as a solid and causes problems in liquid separation with the organic phase. For this purpose, the concentration of the aqueous sodium hydroxide solution in the present invention is selected from 30% by weight or less.
Particularly, 10 to 20% by weight is suitable.

When the method of the present invention is carried out using a heat medium such as hot water or a hot organic solvent, the heat treatment solution becomes acidic due to the acid catalyst remaining in the reaction solution, and the generated tertiary-butoxybenzene derivative is produced. In order to decompose, it is necessary to treat the reaction solution with a small amount of alkali before dropping it. Examples of the alkali used include sodium hydroxide and potassium hydroxide, and sodium hydroxide is preferably used from the viewpoint of economy and the like. Further, it is preferable that the amount used is such that the reaction solution is neutralized. In addition, heat generation by the alkali treatment is hardly recognized. After the unreacted isobutylene is removed, the reaction solution contains an unreacted phenol compound which is difficult to separate by distillation from the tertiary-butoxybenzene derivative. After extracting and removing phenolic compounds,
Preferably, the tertiary-butoxybenzene derivative is separated by distillation from the organic phase. Examples of the alkali used include sodium hydroxide and potassium hydroxide.

When the removed isobutylene gas is recovered by the method of the present invention, it may contain low-boiling substances, water and a reaction solvent by-produced by the reaction in several percent.
When this recovered isobutylene gas is recycled to the next reaction, water may lower the acid strength of the acid catalyst used, adversely affect the reaction, and cause a problem. The moisture in the recovered isobutylene gas can be removed by passing it through a low-temperature condenser to such an extent that the reaction is not adversely affected. The lower the temperature of the condenser, the better the removal capacity and efficiency. However, if the temperature is lower than 0 ° C., it is not good because it adheres to the condenser as ice and blocks the space. The temperature of the condenser capable of removing moisture to such an extent that the reaction is not adversely affected is 15 ° C. or lower, and particularly preferably 0 to 5 ° C. The recovered isobutylene gas that has passed through the low-temperature condenser is absorbed directly or in a reaction solvent and can be suitably recycled for the next reaction.

[0023]

As is apparent from the above description, according to the method of the present invention, a phenol compound is reacted with isobutylene in the presence of an acid catalyst to produce a tertiary-butoxybenzene derivative. Unreacted isobutylene can be quantitatively and efficiently removed from the mixture.

The method of the present invention is extremely simple, has a large industrial value, and is highly practical.

[0025]

EXAMPLES Hereinafter, the method of the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 3 having a thermometer, a stirrer, a reflux cooling pipe and a raw material introduction pipe
In a 00 ml round bottom flask, add chlorobenzene (hereinafter Ph
85.6 g of parachlorophenol (hereinafter abbreviated as PCP) dissolved by heating to 88.6 g.
g (1.00 mol) and 0.24 g (0.0025 mol) of methanesulfonic acid (hereinafter abbreviated as MSA),
While maintaining the liquid temperature at 20 ° C. while stirring, 67.4 g (1.20 mol) of isobutylene gas (hereinafter abbreviated as IBG).
Was fed into the solution over 6 hours. Thereafter, aging was performed at the same temperature for 20 hours. This reaction solution was subjected to GC analysis to determine the reaction results. As a result, the PCP conversion rate was 76.4% and the PTBCB yield was 75.1%. Then, using a metering pump, this reaction solution was weighed in a 500 ml round bottom flask having a thermometer, a stirrer, a reflux condenser through which cooling water at 5 ° C. was circulated, and a gas flow meter and a gas trap at its vent. %
68.4 g (0.342 mol) of aqueous sodium hydroxide solution
For 1.5 hours while maintaining the liquid temperature at 90 ° C. When the gas phase gas during the dropping was measured with a flow meter, it was quantitatively released. The amount of gaseous gas released was 22.9 g, and 22.4 g of isobutylene.
(0.399 mol), water 2200 ppm. Was contained. Almost simultaneously with the end of the dropping, the release of gas was stopped.
The treated liquid was cooled and separated, and the organic phase was taken up. GC analysis of the remaining raw material in the organic phase revealed that isobutylene was 0.08% by weight and PCP was not detected. PhCl and PTBCB were recovered from the organic phase by distillation, but could be recovered in a short time without causing any burden on distillation such as liquid foaming.

Example 2 1.0 g (0.0025 mol) of a 10% by weight aqueous sodium hydroxide solution was added to a reaction solution reacted under the same apparatus, raw materials, preparation and reaction conditions as in Example 1, followed by stirring. Sum processing was performed. This reaction solution was added dropwise to 40 g of water in the same apparatus as in Example 1 over a period of 1.5 hours while maintaining the solution temperature at 90 ° C. When the gas phase gas during the dropping was measured with a flow meter, it was quantitatively released. The amount of gaseous gas released was 23.0 g, and 22.5 g of isobutylene was discharged.
g (0.401 mol), water 2000 ppm. Was contained. Almost simultaneously with the end of the dropping, the release of gas was stopped. This treatment liquid was cooled, and residual isobutylene in the organic phase was analyzed by GC. As a result, it was found to be 0.05% by weight. next,
While stirring the treatment liquid, 28.5 g (0.342 mol) of a 48% by weight aqueous sodium hydroxide solution was added dropwise over 0.5 hours while maintaining the liquid temperature near room temperature. After completion of the dropwise addition, the organic phase was separated by static decantation. GC analysis of the remaining raw material in the organic phase revealed that isobutylene contained 0.1%.
No PCP was detected at 04% by weight.

Comparative Example 1 A 20% by weight aqueous solution of sodium hydroxide 6 was added to a reaction solution reacted under the same apparatus, raw materials, preparation and reaction conditions as in Example 1.
8.4 g (0.342 mol) were added dropwise over 0.5 hour. Thereafter, the liquid temperature was maintained at 90 ° C., and the mixture was heated and stirred for 1.5 hours. During the dropwise addition of the 20% by weight aqueous sodium hydroxide solution and during the heating and stirring, the gaseous phase gas released from the reflux condenser was measured with a flow meter. The amount of gas-phase released gas trapped during this time was 17.7 g, and 17.2 g of isobutylene.
(0.307 mol), water 2500 ppm. Was contained. The treated liquid was cooled and separated, and the organic phase was taken up.
GC analysis of the remaining raw material in the organic phase revealed that isobutylene was 2.1% by weight and PCP was not detected. PhCl and PTBCB were recovered from this organic phase by distillation, but the liquid foamed vigorously and it took a long time to recover. Also,
The burden of distillation was extremely high, including complicated operations such as isobutylene trap.

Comparative Example 2 The reaction was carried out under the same apparatus, raw materials, preparation and reaction conditions as in Example 1 and the results were determined. The PCP conversion was 76.2%.
The PTBCB yield was 75.1%. This reaction solution was added dropwise to 40 g of water in the same apparatus as in Example 1 over a period of 1.5 hours while maintaining the solution temperature at 90 ° C. When the gas phase gas during dropping was measured by a flow meter, the flow rate fluctuated greatly and was released non-quantitatively. The amount of gas-phase released gas trapped was 31.7 g, and 30.9 g of isobutylene.
(0.55 mol), water 2400 ppm. Was contained. The treated liquid was cooled and separated, and the organic phase was taken up. The organic phase was analyzed by GC to determine the PTBCB yield.
0.2%, and about 20% of the produced PTBCB was decomposed.

Example 3 1 having a thermometer, a stirrer, a reflux cooling pipe and a raw material introduction pipe
In a 2,000 ml round bottom flask, 385.8 g (3.00 mol) of PCP and 0.72 g (0.0075 mol) of MSA dissolved by heating with 256.8 g of PhCl were charged, and the liquid temperature was maintained at 20 ° C. with stirring. While IBG20
2.2 g (3.60 mol) were fed into the solution over 6 hours. Thereafter, aging was performed at the same temperature for 20 hours. This reaction mixture was subjected to GC analysis to determine the reaction results. As a result, the PCP conversion was 76.8% and the PTBCB yield was 75.3%. Next, the reaction solution was subjected to a thermometer, a stirrer, and a reflux cooling pipe through which cooling water at 5 ° C. was circulated using a metering pump.
A fixed amount was dropped into 205.2 g (1.026 mol) of a 20% by weight aqueous sodium hydroxide solution in a 00 ml round bottom flask over 6 hours while maintaining the liquid temperature at 90 ° C. The reaction was carried out under the same apparatus, raw materials, preparation and reaction conditions as in Example 1 except that the recycled IBG discharged from the reflux condenser during this dropping was used. The reaction solution was subjected to GC analysis to determine the reaction results. As a result, the PCP conversion was 76.1%, the PTBCB yield was 75.0%, and the unreacted isobutylene was recyclable.

Claims (2)

[Claims] 1. A method for producing a tertiary-butoxybenzene by reacting a phenol compound with isobutylene in the presence of an acid catalyst. To obtain a tertiary-butoxybenzene derivative.
A method for producing a butoxybenzene derivative. 2. A method for producing a tertiary-butoxybenzene by reacting a phenol compound with isobutylene in the presence of an acid catalyst, wherein an unreacted raw material is removed by dropping a predetermined amount of the alkali-treated reaction solution into a heating medium. Then, a tertiary-butoxybenzene derivative is obtained by distillation.