JPS6197236A - Preparation of 2-alkenylcatechol - Google Patents

Abstract

PURPOSE:To produce the titled compound and to facilitate the removal of copper deposited during the reaction, by hydrolyzing 2-alkenyl-6-chlorophenol in an aqueous solution of caustic alkali in the presence of a copper compound catalyst using a reactor made of a fluoroplastic. CONSTITUTION:3-Alkenylcatechol is produced by hydrolyzing 2-alkenyl-6- chlorophenol in an aqueous solution of caustic alkali in the presence of a copper compound catalyst (preferably copper oxide), using a reactor made of a fluoroplastic at the parts contacting with the reaction mixture e.g. reaction vessel, stirring blades, stirring shaft, buffle, etc. Metallic copper deposited on the reactor during the reaction can be recovered easily by the use of the reactor made of a fluoroplastic, and the reaction can be continued in high stability.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to 3-alkenylcatechol (hereinafter referred to as JAC!T
The details are related to the method for producing jAOT by hydrolyzing J-alkenyl-6-chlorophenol (hereinafter referred to as 2AOF) using a copper compound as a catalyst. . j-ACT is useful, for example, as an intermediate in the production of the insecticide carbofuran.

[Prior Art] - A method for producing J'ACT, for example 3-inbutenylcatechol, by hydrolyzing 2-inbutenyl-6-chlorophenol according to the following reaction formula is known. (Refer to % Kaisho!!-/7 Ko 332) This hydrolysis reaction is carried out in a caustic aqueous solution, for example.
It has been carried out using copper compounds such as copper oxide as a catalyst.

[Problem that the invention seeks to solve]

However, when the hydrolysis reaction of 2AOF is carried out using this method, although the corresponding JAOT is efficiently produced, metallic copper is precipitated during the reaction, and this deposits adhere to the inner wall of the reactor, stirring blades, etc. It has its drawbacks. Therefore, either the metal steel cannot be efficiently recovered from the mixture after the reaction is completed, or it is difficult to uniformly stir and extract the reaction mixture, and a stable reaction cannot be maintained.

In view of the above circumstances, the present invention aims to 2) provide a method for preventing precipitated metallic copper from adhering to the inner wall of a reactor, etc. when CP is hydrolyzed in an aqueous caustic solution using a copper compound as a catalyst; That is.

[Means for solving problems]

The gist of the present invention is to produce JACjT by hydrolyzing JAOP in an aqueous caustic solution using a copper compound as a catalyst.
jAc!, characterized in that the reaction device in contact with the reaction mixture is made of a fluororesin. It consists in the manufacturing method of T.

The present invention will be explained in more detail below.

In the present invention, JAOP is hydrolyzed to produce the corresponding 3ACT, but the co-AOP is usually one in which the alkenyl group has 2 to 2 carbon atoms, such as coptenyl-6-chlorophenol, co-inbutyl group, etc. Teniloo 4-
Chlorphenol, J-(J-methyl-7-butenyl)
-6-chlorophenol, λ-(2-ethyl-7-butenyl)-two-chlorophenol, and the like.

The hydrolysis reaction of 2ACP, which is the subject of the present invention, is carried out in an aqueous caustic solution using a copper compound as a catalyst. Copper compounds typically include cuprous oxide, cupric oxide, cuprous chloride, cupric chloride, cuprous sulfate, and the like, with copper oxide being preferred. The amount of these copper compounds used is usually 1.2 AC! As cu for P, o, oor~
1 mole times, preferably 0.0! -0.3 mole times.

On the other hand, the caustic alkali is usually caustic soda or caustic potash, and the amount used is, for example, co-r mole times, preferably 2-≠ mole times, relative to 2 ACP. The concentration of the caustic aqueous solution is usually 0.1 - j i amount, and the amount of this aqueous solution used is usually ! ~ioo times the weight. In the present invention, additives other than the copper compound, such as co-catalysts or surfactants, may be used in combination, if necessary.

The temperature of the hydrolysis reaction is usually l≠0-200°C, preferably /! The pressure may be any pressure that can maintain the reaction mixture in the liquid phase, and is usually ≠ to /7 to 9/aA at the above temperature. If the reaction temperature is too low, the reaction rate will be slow; on the other hand, if the reaction temperature is too high, the metallic copper that precipitates during the reaction will agglomerate, and not only will it fail to form uniform fine particles, but will also result in the desired jA.

This is not preferable because the yield of T also decreases. Further, the reaction time is usually about o, r to j hours.

The reaction of the present invention can be carried out either continuously or batchwise; however, as a reactor, a normal stirred tank type is used. reactor can be used.

In the present invention, it is an essential requirement that the reaction device in contact with the reaction mixture be constructed of a fluororesin. The reaction apparatus usually includes a reactor, a stirring blade, a stirring shaft, a baffle, a raw material supply pipe, a reaction mixture withdrawal pipe, and the like. If at least a part of the surface in contact with the reaction mixture in these devices is composed of a fluororesin, the effects of the present invention can be obtained accordingly, but usually at least the reactor, preferably the stirring blade, and the stirring blade The entire surface of the reactor that comes into contact with the reaction mixture, including the shaft, panfur, raw material supply pipe, and extraction pipe, is made of fluororesin.

Examples of the fluororesin typically include difluoroethylene resin, tetrafluoroethylene resin, vinylidene fluoride resin, tetrafluoroethylene-hexafluorotetrapropylene copolymer resin, and tetrafluoroethylene-ethylene copolymer resin.

The reaction devices in contact with the reaction mixture can be constructed of fluororesin by making these devices made of fluororesin, or by forming a fluororesin surface on the inside of the device by any means such as coating or lining.

After the reaction is completed, the pressure of the mixture is usually lowered to normal pressure, and then the precipitated fine particles of copper metal are separated by filtration. For example, by setting the F liquid to pg≠ or less, JAO
The desired JAOT can be recovered by forming a crystal or oil layer containing T, then separating this, and then performing recrystallization or distillation as necessary.

〔Example〕

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example: Three autoclaves each having an internal volume of 100 liters and having a stirrer, a heating jacket, a raw material supply pipe, a reaction mixture withdrawal pipe (overflow pipe), and a thermometer protection pipe are connected in series, and all the inner walls of the reactor are connected in series. The reaction was carried out using a reaction apparatus made of fluororesin. (The main body of the reactor is a container made of tetrafluoroethylene resin, the stirrer blades and the shaft are coated with hydrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin, and the reaction mixture outlet pipe is made of tetrafluoroethylene resin. using a pipe,
(The other piping was covered with a tube made of tetrafluoroethylene-hexafluoropropylene copolymer resin.) The reaction was carried out through the raw material supply pipe of the first reactor with 1,2-isophthynyl-6-chlorophenol. (hereinafter referred to as BCPL)
φ weight % containing cuprous oxide and cuprous oxide - caustic soda aqueous solution (
NaOH/BOFL=J, J molar ratio), au, o/
B CP L=0, / (molar ratio)) was continuously supplied with a pump so that the residence time in each reactor was 44j minutes, the reaction temperature in each reactor was 170 ° C., and the reaction pressure was / Continuous reaction was carried out for an iot period of time while the reaction mixture was being withdrawn from the reaction mixture extraction pipe of the third reactor.

After the reaction was completed, the reaction mixture remaining in the reactor was extracted, the reactor was disassembled, and the metal copper adhering to the walls was peeled off.The total amount was determined to be 3? Met.

In addition, after filtering the recovered reaction mixture and separating the precipitated metallic copper (total recovery amount jO!, rit), the reaction solution was analyzed to determine the reaction results, and it was found that the conversion rate of BC!PIJ was 1
2%, the desired product 3-inbutenylcatechol (
The selectivity of BOTL (hereinafter referred to as BOTL) was 72%.

Example λ In the method of Example 1, stainless steel coated with a Tatrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin was used as the reactor body. ! (SUS
Using a J/D container, the raw material mixture was supplied so that the residence time in each reactor was 6Q minutes, and continuous reaction was carried out at a temperature of 1.degree. C. for 7.lambda. hours.

Thereafter, the treatment was carried out in the same manner as in Example/, and the amount of metallic copper adhering to the inner wall surface of the reactor was determined, and it was found to be 3.2
? The conversion rate of BOPL was rj% and the selectivity of BOTL was 70%.

Comparative Example 1 In the method of Example 2q, continuous reaction was carried out for 77 hours using a reactor made entirely of stainless steel (stirring blades were 5U830≠, others were 8Us 3/A) without having the surface made of fluororesin. I did this.

Thereafter, the process was carried out in the same manner as in Example C, and the amount of metal steel adhering to the inner wall of the reactor was determined. J J 44. ♂? Met. Also, BOPL
17) Conversion rate was r2% and BCTL selectivity was 73%.

Comparative Example In the method of Example 3, continuous reaction was carried out for 2≠ hours using a reactor whose surface was made of copper (the reactor body was a copper container, and the rest was copper plated).

Thereafter, the process was carried out in the same manner as in Example A, and the amount of metallic copper adhering to the inner wall of the reactor was 72.62, and the tip of the stirring blade and a part of the inner wall were plated or fused. Copper was recognized. Also, the conversion rate of BOPL is go%, BOTL
The selectivity was 73%.

〔Effect of the invention〕

According to the present invention, when producing JACT by hydrolyzing λACP using a copper catalyst, adhesion of copper metal to the inner wall of the reactor is almost prevented. Therefore, the operation for recovering the copper catalyst is simple, and the effective volume within the reactor is not nitrided, so a stable reaction can be carried out at all times.

Sender: Mitsubishi Chemical Industries, Ltd. Representative Patent Attorney Hase - 1 other person

Claims (2)

[Claims] (1) In a method for producing 3-alkenylcatechol by hydrolyzing 2-alkenyl-6-chlorophenol in an aqueous caustic solution using a copper compound as a catalyst, the reaction apparatus in contact with the reaction mixture is constructed of a fluororesin. A method for producing 3-alkenylcatechol, characterized by: (2) The reaction device in contact with the reaction mixture is a reactor, a stirring blade,
The method for producing 3-alkenylcatechol according to claim 1, characterized in that the method is a stirring shaft or a buffer.