JPS6223744B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for producing ketazine corresponding to the ketone used by reacting neutral hydrazine sulfate with a ketone, which produces ketazine that can be easily hydrolyzed with water. be. Ketazine is useful as an intermediate for the production of hydrazine because hydrated hydrazine can be obtained by hydrolysis.

Known methods for producing ketazine include the reaction between hydrated hydrazine and a ketone, the reaction between ammonia and chlorine or sodium hypochlorite and a ketone, and the reaction between ammonia, hydrogen peroxide and a ketone. A method based on the reaction of hydrazine and ketone is not known. Furthermore, by achieving this technology, we have established a technology that can hydrolyze benzophenoneazines, which could previously only be hydrolyzed using mineral acids, using only water. In other words, the reaction formula (1) below is, for example, Compt
rend. vol. 169 (1919) p. 239, Reaction formula (2) is from US Patent No. 2870206, Reaction formula (3) is from another application by the present inventors, Reaction formula (4) is related to the present application. The reaction formula (5) is, for example, in Japanese Patent Publication No. 50-25920, and by combining these, hydrazine hydrate can be produced from ammonia and air (actually oxygen) without producing by-products. It is clear that this technology is extremely useful industrially.

2(C ₆ H ₅ ) ₂ C=O+2NH ₃ →2(C ₆ H ₅ ) ₂ C=NH+2H ₂ O …(1) 2(C ₆ H ₅ ) ₂ C=NH+1/2O ₂ →(C ₆ H ₅ ) ₂ C=N−N=C(C ₆ H ₅ ) ₂ +H ₂ O …(2) (C ₆ H ₅ ) ₂ C=N−N =C(C ₆ H ₅ ) ₂ +N ₂ H ₄・H ₂ SO ₄ +2H ₂ O →2(C ₆ H ₅ ) ₂ C=O+(N ₂ H ₄ ) ₂・H ₂ SO ₄ …(3) The present inventors have completed the present invention as a result of intensive research to achieve the above objectives.

That is, the present invention relates to neutral hydrazine sulfate and a linear alkyl group with the general formula R ₁ -CO-R ₂ (wherein R ₁ and R ₂ may be the same or different, each having 1 to 6 carbon atoms, Represents a branched alkyl group or cycloalkyl group having 3 to 6 carbon atoms, or a linear or branched alkylene group in which R ₁ and R ₂ are taken together to form a linear or branched alkylene group having 3 to 8 carbon atoms. , or a substituted alkyl group or substituted alkylene group in which the hydrogen atom of the alkyl group or alkylene group is substituted with a group that is stable in the reaction medium.) to produce the corresponding ketazine. A method for producing ketazine, characterized by:

In the above, the substituent of the substituted alkyl group or substituted alkylene group, that is, the group stable in the reaction medium, includes, for example, chloro, bromo, fluoro, methoxy, hydroxy group, and the like.

Examples of ketones that can be used in the present invention are:
These include acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, cyclohexanone, and the like.

The amount of ketone used in the present invention can be any number of moles per mole of neutral hydrazine sulfate, but it is generally preferred to use 0.1 to 100 times the mole, and more preferably 1 to 50 times the mole. It is. Note that the amount used is the total amount of ketone present in the entire reaction system.

In the present invention, neutral hydrazine sulfate may be reacted with a ketone in a solid state, or may be reacted with a ketone in an aqueous solution state. In the case of an aqueous solution, the concentration of neutral hydrazine sulfate is not particularly defined.
Furthermore, inorganic salts may be present in the system. Here, the inorganic salts include, for example, hydrazine sulfate, sodium sulfate, ammonium sulfate, aluminum sulfate, magnesium sulfate, sodium chloride, calcium chloride, lithium chloride, potassium chloride, ammonium chloride, etc., but are not particularly limited to these. Note that the presence of inorganic salts may reduce the solubility of certain ketones or ketazine in water, making it easier to separate the organic layer and the aqueous layer.

In the present invention, when a ketone is allowed to act on neutral hydrazine sulfate, an organic solvent that is sparingly soluble in water may be used to dissolve the ketone and ketazine well.
Examples of solvents include pentane, hexane, heptane, decane, cyclohexane, cyclooctane, methylcyclohexane, benzene, toluene, xylene, plaidocumene, mesitylene, dichloromethane, chloroform, carbon tetrachloride, ethylene dichloride, tetrachloroethylene, chlorobenzene, Examples include diisopropyl ether and anisole. Incidentally, it is also possible, of course, to add the solvent after the reaction is completed without using a solvent during the reaction.

In addition, in the present invention, it is not necessary to use the neutral hydrazine sulfate isolated in the reaction (3) above to act on the ketone. This also includes cases where ketazine is immediately produced from neutral hydrazine sulfate produced in the presence of the ketone of the present invention.

The reaction temperature is usually preferably in the range of 0 to 150°C, more preferably in the range of 20 to 100°C.
In addition, when carrying out the process at a high temperature, it may be desirable to apply pressure.

The reaction time varies depending on the type of ketone in the reaction system, the composition of the ketone and neutral hydrazine sulfate, the reaction temperature, the operating method, etc., but is usually in the range of 1 minute to 10 hours and may be selected as appropriate.

Although the present invention is carried out as described above, examples of preferred methods will be further explained in relation to specific operating methods.

In the case of batch operation, a neutral hydrazine sulfate aqueous solution, a ketone, and a solvent are charged into a reaction tank so that the composition ratio is within a preferable range, and the temperature is 0 to 100°C.
Allow to react for 1 to 240 minutes while stirring. The liquid after the reaction is immediately phase-separated into an organic layer and an aqueous layer, and when the temperature is low, the produced acidic hydrazine sulfate is precipitated in the phase-separated aqueous layer. The reaction rate of neutral hydrazine sulfate can be determined, for example, by quantifying ketazine in the organic layer or from the hydrazine content in the aqueous layer. The aqueous layer can be used repeatedly in the reaction of reaction formula (3). Hydrazine hydrate can be obtained from the organic layer as it is or by distilling off the ketone and solvent and hydrolyzing it by a known method.

In the case of continuous operation, the reaction is carried out using a batch reactor, a cocurrent multistage reactor, preferably a countercurrent multistage reactor. For example, when a single tank reactor is used, at the start of the reaction, the reaction solution that has reached a predetermined reaction rate is charged into the reaction tank by batch operation, or only the neutral hydrazine sulfate aqueous solution, ketone solution, or both. and then heat the solution to 0-100℃.
Then, the neutral hydrazine sulfate aqueous solution and the ketone solution are continuously fed to the reaction tank using pumps, respectively. The flow rate is adjusted so that a predetermined molar ratio of neutral hydrazine sulfate and ketone is maintained and a predetermined residence time is obtained. Adjust the flow rate so that the residence time per tank is 5 to 240 minutes. The reaction solution is extracted and separated into an aqueous layer and an organic layer. The subsequent operations are similar to those for batch operations.

By the above operations, a steady state is usually achieved within several minutes to several hours, and stable operation can be maintained for a long period of time thereafter.

The extracted reaction liquid was separated into two layers, and the separation state was very good. The reaction solution is treated in the same manner as in the batch operation.

The method of the present invention as described above allows quantitative reaction, is less likely to cause side reactions such as aldol condensation of ketones, and is extremely easy to recover ketones, ketazine, and hydrazine sulfate. The operational loss is also extremely small. Ketazine obtained in the present invention is hydrolyzed only with water under pressure and easily becomes hydrazine hydrate.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 5.0 g of neutral hydrazine sulfate in a 100 ml four-necked flask equipped with a stirrer, thermometer, and reflux condenser.
(0.0308 mol) and methyl ethyl ketone 45.0 g
(0.6240 mol) was charged and reacted for 5 minutes at reflux temperature (79°C). After the reaction was completed, methyl ethyl ketone and methyl ethyl ketazine were determined in the organic layer by gas chromatography to determine the yield of methyl ethyl ketazine, which was 80.0% based on neutral hydrazine sulfate. Moreover, the quantitative value of hydrazine in the aqueous layer also showed the same value.

Comparative Example 1 5.0 g (0.038 mol) of acidic hydrazine sulfate and 45.0 g (0.624 mol) of methyl ethyl ketone were added to Example 1.
The reaction was carried out under the same conditions.

There was only trace formation of methyl ethyl ketazine.

Example 2 Into the same flask as in Example 1, 15.0 g of a 10.54% neutral hydrazine sulfate aqueous solution [(N ₂ H ₄ ) ₂ .
H ₂ SO ₄ 9.75 mmol] and methyl ethyl ketone 3.5
(48.53 mmol) and 10.0 g of toluene and reacted for 5 minutes while cooling to 4°C. As soon as stirring is stopped, the mixture separates into two layers, and when the organic layer is separated, methyl ethyl ketazine is obtained. The yield of ketazine was 64.5% based on neutral hydrazine sulfate.

Example 3 Into the same flask as in Example 1, 6.0 g (3.90 mmol) of a 10.54% neutral hydrazine sulfate aqueous solution was added.
and methyl ethyl ketone 14.1 g (195.51 mmol)
and 40 g of toluene were charged and reacted for 5 minutes at room temperature (27°C). When stirring was stopped, the mixture immediately separated into two layers, so the organic layer was separated to obtain methyl ethyl ketazine. The yield of ketazine based on neutral hydrazine sulfate is
It was 98.5%.

Example 4 In a flask similar to Example 1, 30.0 g (9.75 mmol) of a 10.54% neutral hydrazine sulfate aqueous solution was added.
, 9.8 g (97.8 mmol) of methyl isobutyl ketone, and 20.0 g of xylene were prepared, and the mixture was heated to reflux temperature (94 mmol).
℃) for 2 hours. When the stirring was stopped, the mixture immediately separated into two layers, so the organic layer was separated to obtain methyl isobutyl ketazine. The yield of ketazine was 66.9% based on neutral hydrazine sulfate.

Example 5 A separate reactor consisting of a cylindrical glass container with an internal volume of 1 and a lid was used. A liquid supply line for a toluene solution of methyl ethyl ketone and a neutral hydrazine sulfuric acid aqueous solution are attached to the opening in the lid, and a cooler and a thermocouple sheath tube are attached to the other two openings, and a stirrer is attached to the opening in the center of the lid. A stirring blade was inserted through the tube. Also, on the wall of the reactor,
Two Teflon baffles were installed to ensure effective mixing. A reaction liquid outlet is provided near the bottom of the reactor, a glass tube is inserted through this outlet, and the length of the tube is adjusted to maintain the amount of liquid retained in the reactor. I did it like that.

Adjust the length of the insertion tube at the extraction port so that the amount of liquid retained is 500ml, then add 360g of a solution with a composition of 25.9wt% methyl ethyl ketone and 74.1wt% toluene and neutral sulfuric acid with a concentration of 10.54wt%. After charging 80 g of hydrazine aqueous solution and carrying out a batch reaction for 10 minutes at room temperature (27°C), 342 g/Hr of a toluene solution of methyl ethyl ketone with the exact same composition was added.
94g/10.54wt% neutral hydrazine sulfate aqueous solution
Supply was started using a plunger pump at a flow rate of Hr.

The overflow liquid was stored in a separating tank, and the upper organic layer was extracted from the overflow, and the lower aqueous layer was extracted at regular intervals by opening the pot at the bottom.

After reaching a steady state after about 30 minutes, continuous reaction was carried out for 100 hours, and the following results were obtained. Methyl ethyl ketazine was obtained at a rate of 7 g per hour at a reaction temperature of room temperature (27°C) and an average residence time of 1 hour.
Average ketazine yield is based on neutral hydrazine sulfate.
It was 81.0%.

When the obtained methyl ethyl ketazine solution was hydrolyzed by a known hydrolysis method, hydrated hydrazine was quantitatively obtained. In addition, the hydrazine sulfate aqueous solution could be used as it was for the hydrolysis of benzophenone azine.

Example 6 In a reaction flask similar to Example 1, 1.8 g (0.005 mol) of benzophenone azine, 18.1 g (0.25 mol) of methyl ethyl ketone, and 1.3 g of acidic hydrazine sulfate were added.
(0.01 mol) and 9.0 g of water were prepared, and the reflux temperature (74
℃) for 5 hours, methyl ethyl ketazine was obtained in a yield of 20%. As another product, methyl ethyl ketone benzophenone azine was identified by GC-MS.

Claims (1)

[Claims] Neutral hydrazine sulfate and general formula R ₁ -CO-R ₂ (wherein R ₁ and R ₂ may be the same or different, each having a straight chain alkyl group having 1 to 6 carbon atoms,
Represents a molecular chain alkyl or cycloalkyl group having 3 to 6 carbon atoms, or one in which R ₁ and R ₂ are taken together to form a linear or branched alkylene group having 3 to 8 carbon atoms; Alternatively, it represents a substituted alkyl group or substituted alkylene group in which the hydrogen atom of the alkyl group or alkylene group is substituted with a group that is stable in the reaction medium. ) A method for producing ketazine, which comprises reacting with a ketone represented by the formula to produce the corresponding ketazine.