JPS6156161A - Preparation of 2-methyl-3-pyrazolidone - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a synthetic intermediate of penicillin, antiobesity agent, anti-enzymatic agent, etc., easily, in high yield, from an inexpensive raw material, by the hydrolytic cyclization of N-methyl, N'-beta-cyanoethyl-hydrazine. CONSTITUTION:The objective compound of formula II can be prepared by the hydrolytic cyclization of novel N-methyl, N'-beta-cyanoethyl-hydrazine of formula I in the presence of water, using a mineral acid, preferably hydrochloric acid, sulfuric acid, nitric acid, etc., at the refluxing temperature of water. The starting compound of formula I can be produced by the hydrogenation of formaldehyde beta-cyanoethylhydrazone, 1,4-di(beta-cyanoethyl)hexahydro-1,2,4,5-tetrazine or their mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel method for producing 2-methyl-5-pyrazolidone, which is useful as an intermediate for active ingredients such as penicillin, anti-obesity agents, and anti-enzyme 11, as well as 2-methyl-5-pyrazolidone. A novel N-methyl, Cβ-, which is an intermediate of methyl-5-pyrazolidone
This invention relates to cyanoethylhydrazine and their production methods.

BACKGROUND OF THE INVENTION Conventionally, as a method for producing 2-methyl-6-pyrazo 1Jtone, for example, a method as shown in the following reaction formula is known.

(1) )l, N-NH,, H, O+OH, = 0H
ON-→NH, N1 (OH, OH, ON (I''-muguchi) For the notation method, refer to the following literature.

] t) Volume 69, Tomb 11, 43845vr First, in the method (1), β-7-clot-ethylhydrazine is formed by an addition reaction between hydrazine hydrate and acrylonitrile.

Next, in method (2), after concentrating and dehydrating the reaction mixture with
It is added to 6 equivalents of sulfuric acid using ethanol as a solvent and subjected to a cyclization reaction to produce 5-i novirazolinazine sulfate.

Next, in method (3), this 5-i novirazolidine sulfate is isolated by total filtration and further hydrolyzed in an aqueous solvent to obtain 5-pyrazolidone.

Next, in the method (4), after protecting 3-pyrazolidone from the benzoylated 9 to the 1st position.

The desired 2-methyl-3-pyrazolidone is produced by methylation and further hydrolysis to remove the benzoyl group at the 1-position.

Problems to be Solved by the Invention The conventional method described above has various practical problems, including the following.

In the cyclization reaction of β-cyanoethylhydrazine in the method (2) above, (1) a large amount of sulfuric acid is used, making post-treatment of the residual sulfuric acid complicated;

(→The addition of β-cyanoethylhydrazine to the sulfuric acid dissolved in ethanol was carried out all at once, and the reaction soon proceeded with intense heat generation, and a large amount of crystals instantly precipitated from the homogeneous solution. 9 Mechanical stirring was even stopped. However, it is extremely complicated to operate, as the solvent, ethanol, refluxes violently.

■After this reaction, 5-iminopyrazolidine sulfate is separated from the ethanol solution of sulfuric acid by filtration.
It has poor filterability and requires an extremely long time. In this way, when carrying out the methods (1) and (2) above, there are various operational difficulties. In addition, in the method (1) above, (2) dimethyl sulfate that is permeable to the skin is used. ■By-products are produced in the methylation reaction, resulting in a decrease in yield.

Difficulties in purification methods. - In the hydrolysis reaction, the equivalent mole of benzoic acid is produced as a by-product, making it difficult to purify the target product. As described above, there are various operational difficulties in the steps of this method.

Don't solve the problems (D Means) The present invention solves the various problems of the conventional methods described above, and as a result of various studies on the new method for producing the target 2-methyl-3-pyrazolidone, They found that the best method is to go through all the various manufacturing steps as shown in the above formula, and have completed the present invention.

The manufacturing process of the present invention described above will be explained.

First, when formaldehyde is subjected to a dehydration condensation reaction with cyanoethylhydrazine l obtained by the addition reaction of hydrated hydrazine and acrylonitrile, the heptad-mer compound [v] is obtained, and at the same time, the dimer compound [v]
It also occurs as a by-product.

On the other hand, monomer compound (g) and dimer compound rv
It can also be obtained by first reacting hydrazine hydrazine and formaldehyde to obtain the compounds [h] and [h], and then subjecting them to an addition reaction with acrylonitrile.

Next, the above monomer compound and dimer compound [v]
By separating them and hydrogenating each of them or a mixture thereof, a new compound, N-methyl N/-
β-cyanoethylhydrazine [old] is obtained. Subsequently, this compound +11 is hydrolyzed and cyclized to obtain the desired 2-methyl-3-pyrazolidone [I].

' On the other hand, the desired 2-
Methyl-5-pyrazolidone [I] is obtained. The method of the present invention uses hydrazine hydrate, acrylonitrile and formaldehyde as starting materials, and as intermediates monomer compound [Y], dimer compound [Vl and/or straddle compound] Compared to conventional methods, 2-methyl-3-pyrazolidone CI is industrially advantageous due to its short steps and ease of purification and operability.
] is the manufacturing method.

Next, it will be described in more detail.

In the present invention, cyanoethylhydrazine [1111! -t, can be easily obtained quantitatively by simply mixing hydrazine hydrate and acrylonitrile.

In the present invention, formaldehyde refers to formaldehyde, formaldehyde, and formalin (formaldehyde aqueous solution), and any of these can be used as is.

In the production of a monomer compound [lv] by dehydration condensation reaction between cyanethylhydrazine [(old) and formaldehyde, when a solvent such as water or alcohol is used and mixed at around room temperature, the reaction proceeds with a slight heat generation, and stirring is continued. By continuing the reaction, the reaction is completed.During this reaction, a dimer compound [Vl, which is a dimer of the monomer compound ['M1], is also produced as a by-product.

If only the monomer compound (leopard) is to be isolated from this mixture, one reaction mixture can be concentrated and then distilled out by vacuum distillation. On the other hand, the yield of dimer compound [V] is
In the case of isolation, the dehydration condensation reaction solution is concentrated and the resulting mixture is left at room temperature for 2 to 5 days to solidify the oil. A pure product can be obtained by recrystallizing this from ethanol.

The present inventors also discovered a method for selectively producing the monomer compound rlV1 in good yield.

In other words, the formation of the dimer compound [V] is suppressed by the presence of a small amount of base during the reaction with formaldehyde of ethylhydrazine [nT1],
Only the monomer compound r pieces are obtained with good sales. Examples of bases include sodium carbonate, carbonate, and thorium hydrogen carbonate.

Examples include potassium hydrogen carbonate, potassium hydroxide, potassium hydroxide, sodium acetate, potassium acetate, potassium propionate, and the like.

In the reaction in which hydrazine hydrate and formaldehyde are first reacted to produce compound y] and compound y, the reaction proceeds easily at room temperature. Although the reaction between the obtained compounds [Cylinder] and [Compound 0] and acrylonitrile (IJ) is rather slow, the reaction can be carried out over a little time at around room temperature.

Target monomer compound rlV1 and dimer compound [
You can get an eye. In this reaction as well, when the reaction is carried out in the presence of a base as described above, the selectivity of the monomer compound [■] is improved.

Next, the monomer compound rlV1 or the dimer compound [
[2] In the reaction of hydrogenating a mixture thereof, a hydrogenation metal complex may be used, or in practical terms, it is preferable to use a catalytic reduction method. In this reaction, a highly pure target product can be obtained by using a highly pure monomer compound that is distilled as a raw material.

Also, monomer compound []V] and dimer compound [v]
Even when a mixture of 1 and 2 is used as a raw material, one reaction proceeds sufficiently and the desired product can be obtained.

Even when only the dimer compound [Vl is used as a raw material, the desired product can be obtained.

In addition, the desired product can be obtained by directly carrying out a hydrogenation reaction without separating the monomer compound (■) and the dimer compound (Vl) from the reaction mixture obtained by the reaction of hydrazine hydrate, acrylonitrile, and formaldehyde. . In this hydrogenation reaction, catalysts used include noble metal catalysts such as palladium, platinum, ruthenium, and rhodium, and nickel.

Examples include iron group catalysts such as cobalt, copper catalysts, and the like.

As for the catalyst form, it can be used as a single metal, a solid catalyst such as a supported metal, or a complex. As for the pressure of the hydrogen used, it is desirable to pressurize it slightly since the reaction is slow at normal pressure.

Usually, it is about several yu-G/, ffl to 40 ky-G/J, preferably about 10 to 3 ob-a/ctl.

As the solvent in the hydrogenation reaction, various solvents can be used as long as they do not directly participate in the reaction. For example, n-
Hydrocarbons such as hexane, benzene and toluene, ethers such as tetrahydrofuran and dioxane, esters such as methyl acetate and ethyl acetate, nitriles such as acetonitrile and propionitrile, methanol, ethanol,
propatool, butanol, amyl alcohol, etc.
N, N-') methylformamide (DMF), N,
N-dimethylacetamide (DMA).

1.3-dimethyl-2-imidazolitone (DM Engineering).

Examples include aprotic organic polar solvents such as dimethyl sulfogide (DMBO), tetramethylene sulfone (sulfolane), hexamethylene phosphoramide (HMPA) w N-methylpyrrolidone, and water. Among these solvents, when alcohols, aprotic organic polar solvents, etc. are used, N
-Methyl N/-β-cyanoethylhydrazine [previously obtained] in good yield.

In addition, when using water as a solvent, a product mainly composed of N-methyl N/-β-cyanoethylhydrazine [form] is obtained when the reaction is carried out at a temperature below 70 to 80°C, whereas a product consisting mainly of N-methyl N/-β-cyanoethylhydrazine is obtained when the reaction is carried out at a temperature above 80 to 90°C. and 2-methyl-5-pyrazolidone-based products are obtained. As for reaction temperature in hydrogenation reaction.

It is desirable to heat the mixture to about 50 to 180°C, preferably 70 to 150°C.

N-methyl, N'-β-cyanoethylhydrazine in the reaction mixture obtained by the hydrogenation reaction [formerly, it can be purified by distillation.

This N-methyl N/-β-cyanoethylhydrazine [
In the hydrolysis reaction of "], 2-methyl-5-pyrazolidone can be obtained in good yield even in the presence of water alone. This hydrolysis reaction can also be carried out in the presence of an acid or a base.
It is usually preferable to use an acid. As for the type of acid, mineral acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid are preferable, and hydrochloric acid is particularly preferred.

Sulfuric acid is preferred.

The hydrolysis reaction temperature is preferably the reflux temperature of water, and the reaction is completed within 2 to 4 hours when only water is used, and within 1 hour when an acid is present.

In the 2-methyl-5-vilapridone crude product obtained by the above method or in the hydrogenation reaction.

2- obtained when reacting in water or a water-containing solvent
Methyl-3-pyrazolidone composition can be purified by recrystallization as a mineral acid salt or the like, and a highly pure product can also be obtained by distillation.

The present invention is a novel production method that is easy to operate in industrial implementation and can obtain the desired 2-methyl-5-pyrazolidone in good yield using inexpensive raw materials.

Next, one example of the present invention will be specifically described, but the present invention is not limited to these.

In addition, in the following examples, OID [( is cyanoethylhydrazine []v, MomH is N-methyl.

N'-β-7γnoethylhydrazine (old meaning).

[Example 1] c B ) + 85 y (1 mol) in methanol 30
02, and add 5f of sodium hydrogen carbonate and 52f of formaldehyde (purity 95X) at room temperature. The mixture gradually generates heat and becomes a translucent solution by continuing stirring at around 40°C for about 50 minutes. When this reaction is analyzed by Ht gas chromatography, the peak of the raw material C disappears and a new peak selectively appears. Therefore, the reaction solution was concentrated while keeping the temperature below 50° C., and then subjected to distillation. As a result of analyzing the fraction with a boiling point of 70~b by mass spectrometry (M8) and proton nuclear magnetic resonance spectrum ('[(-NMR),
It was confirmed that this was the desired monomer.

In addition, one water fraction was analyzed by gas chromatography, 'H-NMR
It was confirmed that the monomer purity was 100% and no dimer was contained.

Next, monomer 49F (15M), N,N-dimethylform 76d (DMF') 500f and 5X palladium-activated carbon 21 were charged into a 500m5US autoclave, and stirring was continued at 90°C for 5 hours at a constant hydrogen pressure of 151G/d. A decrease in the hydrogen pressure in the pressure accumulator of approximately LL5 moles was observed, and hydrogen absorption stopped. After the autoclave was returned to room temperature and the residual hydrogen in the autoclave was released, 9 reaction liquids were taken out, the catalyst was separated, and the mixture was concentrated to obtain 522 reaction mixtures.

When this reaction mixture is completely distilled, the boiling point is 110-112℃/1
A fraction 56f of 011Hf was obtained.

The analysis results of this fraction are as follows.

Purity: 96X (gas chromatography analysis) Mass spectrum (FD method): 99°C M+)'H-NMR (D, O
): 2.45(OH,), 2.55~172(
C! H,).

2.85~15(O[-1,) (δppm)IR(N
aO6): 2220 (OHM) (txt-')
From the above, it was found that this fraction was N-methyl N/-β-cyanoethylhydrazine (IJOKH).

Further, the yield of 2-methyl-5-pyrazolidone was measured by gas chromatography analysis of a portion of the reaction solution immediately after hydrogenation, and the yield from the monomer was 87X.

Note that the gas chromatography analysis conditions are as follows.

Model: oc-6a (manufactured by Takasugi Seisakusho) Detection part:
FID column: glass column, internal diameter 5 m, length 1 m.

Filler: PKG-20M (manufactured by Gascro Industries) 5wtX.

Carrier Unipprt HPS, 80-100 mesh force Ram temperature: 12o-200℃ Heating rate 6℃/min Injection temperature: 280℃ Carrier gas: N, 60*//m1nFl,
: (L6kp-G/cdAir:
1 ks+-G/c1i internal standard substance: N-methylpyrrolidone [Example 2] vaPH (pure 996X) 1 (L12 (alt-ol) was dissolved in water 50 fVC, and this nKI hydrochloric acid (55X) 1
The mixture was stirred for 1 hour under reflux in a 150°C bath. After the reaction was completed, the mixture was cooled and neutralized, concentrated and the solvent was distilled off. The residue was extracted with ethanol, and the ethanol was distilled off to obtain a 10f oily substance. Mass spectrum, NIJ
From R and Engineering R, the target compound was identified as 2-methyl-3-pyrazolidone. Furthermore, as a result of measuring the purity of this oily substance by gas chromatography, it was found that 2-methyl-
Please note that 3-pyrazolidone is 98N.

Therefore, the yield of 2-methyl-5-pyrazolidone from MOBH is V'i98N.

[Example 3] As a result of carrying out the same treatment as in Example 2 except that only water was added at 100F without adding concentrated hydrochloric acid and reflux was continued for 4 hours in a 150°C bath, an oily substance of 9.8F was obtained. It was done. The purity of this oily substance was determined by gas chromatography.

2-methyl-5-pyrazolidone was 86N. Therefore, the yield of 2-methyl-5-virazolidone from MOBH is 1
-184X.

[Example 4] The reaction was carried out in the same manner as in Example 2 except that 3f of bisulfuric acid (95N) was used instead of concentrated hydrochloric acid and the reaction time was changed to 40 minutes, and post-treatment was performed. As a result, a 99f oily substance was obtained, and the purity of 2-methyl-5-pyrazolidone was 88% based on gas chromatography analysis. Therefore, the yield of 2-methyl-5-pyrazolidone from MOKI was 87X.

[Example 5] Aqueous solution of monomer (purity 96X) 10.11 (I), 1 mol) dissolved in 70 liters of water and 5X palladium-activated carbon α
4f was placed in a 200dSUil autoclave. When hydrogen was further stirred at 90° C. for 3 hours at a pressure of 15 g/-, a decrease in hydrogen pressure in the pressure accumulator of about a1 mol was observed and hydrogen absorption stopped. After the autoclave was returned to room temperature and the residual hydrogen in the autoclave was released, one reaction solution was taken out and the catalyst was removed from the furnace and concentrated to obtain an oily substance of 9.8 f. This reaction was repeated four times to obtain 392 fi of 9 reaction sets. The boiling point of this reaction mixture was reduced to 75.degree. by total distillation. Analysis of this fraction by mass spectrometry and NMR revealed that it was 2-methyl-3-pyrazolidone. Further, the purity of 2-methyl-5-pyrazolidone was 97X as determined by gas chromatography. Furthermore, as a result of gas chromatography analysis of a portion of one reaction solution, the yield of 2-methyl-5-pyrazolidone was 70%.

[Examples 6 to 14] The reaction was carried out in the same manner as in Example 5, except that the solvent type, catalyst type, and temperature conditions were changed. [Example 15] 0EF(42-5f((15 mol) Dissolve in 200f of water, 42.9t of 55X formalin aqueous solution (CL5 mol)
was added dropwise at 20 to 25°C while removing heat.

After the dropwise addition, stirring was continued for 1 hour at room temperature, and then the mixture was concentrated and the solvent was distilled off to obtain 50 tons of oily substance. This oily substance at room temperature
It was completely solidified when left to stand day and night. When this solid was recrystallized from ethanol, 59 tons of crystals with a melting point of 122-125°C were obtained.
I got it.

This crystal was found to be 1,4-
Cy(β-cyanoethyl)hexahydro-1,2,4
, 5-tetrazine (dimer). Next, 9.7 t (105 mol) of this dimer.

5X palladium-activated carbon 4F, ethanol 70F 2
00dsU was placed in an autoclave. Furthermore, hydrogen was added at a constant pressure of 15 kg-G/d.

When stirring was continued for 4 hours at 100° C., a decrease in hydrogen pressure in the pressure accumulator of about Q.05 mol was observed, and hydrogen absorption stopped. After returning the autoclave to room temperature, the remaining hydrogen in the autoclave was released, and the 9 reaction liquids were taken out, the catalyst was separated from P, and the mixture was concentrated to obtain an oily substance of a2F.

Furthermore, this oily substance was dissolved in water 201, concentrated tg acid (5
5 yen) 50 P'i were added and stirred for 1 hour while refluxing in a 150°C bath. After the reaction was completed, the mixture was returned to room temperature, neutralized by adding an alkali, and then concentrated to remove the solvent. Further analysis of this concentrate by extraction with ethanol revealed that it contained 2-methyl-5-pyrazolidone, and as a result of quantitative determination by gas chromatography, the purity was 53.

Therefore, the overall yield of 2-methyl-5-pyrazolidone from the dimer was 27N.

[Example 16] 9.7 t (0.05 mol) of dimer, 5X (radium-activated carbon [14F], and 702 g of water were charged into an autoclave for 200 g SU day. Furthermore, hydrogen was added to a pressure of 15 9 G
/c++! After stirring for 2 hours at constant pressure at 120° C., a decrease in hydrogen pressure in the pressure accumulator of about 0.005 mol was observed and hydrogen absorption stopped. After returning to room temperature and releasing residual hydrogen in the autoclave from 75≧, take out one reaction solution and add catalyst f.
After separating f1F and concentrating it, an oily substance of 9.6F was obtained. As a result of analyzing this oily substance using gas-mass spectroscopy,
It was found that 2-methyl-3-pyrazolidone was contained, and its purity +1 was determined by gas chromatography to be 21.%. Therefore, the yield of 2-methyl-3-pyrazolidone from the dimer was 1t20X.

[Example 17] OKHa5 F ([11 mol) IDMIF 70 f
l/C bath-washed paraformaldehyde (M degree 95 yen) 12
1 at room temperature. The temperature gradually increases to around 40℃, which is about 3 degrees.
After stirring for 0 minutes, the solution becomes clear. This reaction solution 12
00mlUs autoclave, add 5X palladium-activated carbon 114ff, and hydrogen pressure 15kp.
When stirring is continued for 3 hours at 90℃ at G/cI & constant pressure, approximately (11
A decrease in hydrogen pressure in the molar pressure accumulator was observed, and hydrogen absorption stopped.

After returning the autoclave to room temperature, the remaining hydrogen in the autoclave was released, and the entirety of the 9 reaction liquid was poured out, the entire catalyst was removed from the furnace, and the autoclave was concentrated to obtain a 1α8F oily substance. The results of analyzing this oily substance using gas chromatography.

It was found that MOEI-1 was contained with a purity of 61X. Therefore, the yield of M(!KH from 0EFI was 66X.

[Example 181 Hydrazine hydrate (pure 1f 80%) 6.5r (α1 mol)
5.49 ([11 mol)] of acrylonitrile (purity 99) was added dropwise to the mixture of water 601 and water at 15 to 25°C over about 50 minutes. Thereafter, stirring was continued for 5 hours at around 50°C. Next, add and dissolve sodium carbonate α3v, then formalin (pure 1f55X) a6f-f15~25
It was added dropwise at ℃. After the dropwise addition, stirring was continued for 1 hour at room temperature, and the mixture was directly charged into a 200m6SU8 autoclave.

Furthermore, add 5X palladium-activated carbon α4f and hydrogen pressure 15
Stirring was performed at 90° C. for 2 hours at h-G/all. Approximately [1
A decrease in the hydrogen pressure in the pressure accumulator of 1 molar was observed, and hydrogen absorption stopped. After the autoclave was returned to room temperature and the residual hydrogen in the autoclave was released, the reaction solution was taken out and the entire catalyst was separated from the reactor, and the obtained reaction solution was subjected to quantitative analysis using gas chromatography. As a result, 2-methyl-5-pyrazolidone was 14
It was found that 1 was produced. Therefore.

2 from the starting material hydrazine hydrate, acrylonitrile
-Methyl-3-pyrazolidone yield was 64X @ [Example 19] After dissolving 6.5f (11 mol) of hydrazine hydrate (purity 80X) in ethanol 601, potassium carbonate α5f and paraformaldehyde (purity 95X) K2F (11 mol)
i Addition at room temperature.

After further stirring at 30-40°C for 1 hour.

Acrylonitrile (purity 99 yen) 5.49 at room temperature
It was added dropwise over 0 minutes. After further stirring at room temperature for 5 hours, the reaction solution was charged into the Oma 200 autoclave. Further, 0.4 f of 5X palladium-activated carbon was added, and the mixture was stirred at 90° C. for 2 hours at a hydrogen pressure of 15 kJi and G/cII. A decrease in hydrogen pressure in the pressure accumulator of about 105 moles was observed, and hydrogen absorption stopped. After the autoclave was returned to room temperature, the residual hydrogen in the autoclave was released, the reaction solution was taken out, and the catalyst was separated from each other.The obtained reaction solution was quantitatively analyzed by gas chromatography. As a result, it was found that MOEH generates i1F.

Therefore, the yield of MOKH from the starting material, hydrazine hydrate, was 51%.

Patent applicant: Nissan Chemical Industries, Ltd. -30 complete-

Claims (6)

[Claims] (1) The following formula: CH_3NHNHCH_2CH_2CN The following formula is characterized by hydrolytic cyclization of N-methyl, N'-β-cyanoethylhydrazine: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Represented by Method for producing 2-methyl-3-pyrazolidone. (2) N-methyl, N'-β-cyanoethylhydrazine represented by the following formula: CH_3NHNHCH_3CH_2CN. (3) Formaldehyde β-cyanoethylhydrazone represented by the following formula: 〇H_3=N-NHCH_2CH_2CN or 1,4-di(β-cyanoethyl)hexane represented by the following formula: ▲ Numerical formulas, chemical formulas, tables, etc. are available▼ A method for producing N-methyl, N'-β-cyanoethylhydrazine represented by the following formula: OH_3NHNHCH_2CH_3CN, which comprises hydrogenating hydro-1,2,4,5-tetrazine or a mixture of both. (4) Formaldehyde β-cyanoethylhydrazone represented by the following formula: CH_3=N-NHCH_2CH_2CN or 1,4-di(β-cyanoethyl)hexahydro represented by the following formula: ▲Mathematical formulas, chemical formulas, tables, etc. are available▼ 2, which is characterized by hydrogenating -1,2,4,5-tetrazine or a mixture of both in water or a water-containing organic solvent and is represented by the following formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ -Method for producing methyl-5-pyrazolidone. (5) hydrazine and acrylonitrile are reacted in the presence of water, then formaldehyde is added and reacted,
A method for producing 2-methyl-3-pyrazolidone represented by the following formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼, which is characterized in that the reaction mixture is then hydrogenated. (6) N-methyl, N'-β-cyanoethyl represented by the following formula: CH_2NHNHCH_2CH_2CN, characterized by reacting hydrazine and formaldehyde, then adding and reacting acrylonitrile, and then hydrogenating the reaction mixture. Method for producing hydrazine.