JPH0558423B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing unsaturated nitrile compounds. Specifically, the present invention deals with acrylonitrile and the general formula () in the presence of a catalyst. (wherein, R ¹ represents a methyl group or 3-cyano-propyl group) is reacted with isobutylene or a derivative thereof represented by the general formula () (In the formula, R ¹ is the same as defined above.) The present invention relates to a method for producing an unsaturated nitrile compound represented by the following formula.

[Conventional technology]

Unsaturated nitrile compounds represented by the general formula () are useful as intermediates in various organic synthesis reactions, and dinitrile compounds in particular are important intermediates for producing fiber-grade polyamides.

It is conventionally known that an unsaturated nitrile compound represented by the general formula () can be synthesized by reacting acrylonitrile with isobutylene represented by the general formula () or a derivative thereof.

U.S. Patent No. 2,641,607 describes a high temperature of 215-330℃
It is described that the reaction proceeds under high pressure conditions of 1025 atm. US Pat. No. 3,898,268 describes a method in which the reaction is carried out in the presence of catalytic amounts of boric acids. Additionally, U.S. Patent No. 3,996,262 states:
A process is described which is carried out in the presence of an organic derivative promoter from group V _A of the periodic table.

[Problem that the invention seeks to solve]

However, in the above-mentioned methods, since the reaction rate is not sufficient, it is necessary to use high temperature conditions, and therefore, it has been required to use severe pressure conditions.

[Means for solving problems]

The present inventors conducted research on a method for producing unsaturated nitrile compounds advantageously in an industrial process by carrying out the reaction at a sufficiently high reaction rate even under mild reaction conditions. The present invention was achieved based on the novel fact that the object can be achieved by reacting acrylonitrile with isobutylene or a derivative thereof in the presence of an acid catalyst.

The present invention will be explained in detail below.

In the method of the present invention, acrylonitrile of ordinary industrial purity is used.

Isobutylene or its derivative represented by the general formula () specifically includes isobutylene and 5
-Methyl-5-hexenonitrile. Isobutylene itself may be used alone, or 1-
It can also be used in the form of a mixture with hydrocarbons such as butene and/or 2-butene. Furthermore, it is also possible to coexist with diluents such as nitrogen, helium, argon, carbon gas, etc. that do not harm the reaction. 5-Methyl-5-hexenonitrile is synthesized as the primary product in the reaction of acrylonitrile and isobutylene in the process of the invention.

5-Methyl-5-hexenonitrile can be used alone, in the form of a mixture with its raw material isobutylene, or in the form of a mixture with 5-methylenenonanedinitrile, which is a secondary reaction product of acrylonitrile. Both can be used. Diluents that do not harm the reaction may also be used in combination as appropriate.

The reaction according to the method of the present invention is carried out in the presence of a specific Lewis acid catalyst. As a measure of Lewis acid in the method of the present invention, SJBnyan, PG
Huggett, K. Wada, J.A.Daniels and J.R.
Jennings, Coond.Chem.Rev., 44 , 149 (1982)
Adopt the △ν _C ≡ _N value described in (Equation (1)) △ν _C ≡ _N = ν _C ≡ _N (CH ₂ = CH−CN・ML _o )−ν _C ≡ _N
(CH ₂ = CH-CN)...(1) (Here, ν _C ≡ _N (CH ₂ = CH-CN) is the stretching frequency of the C≡N bond in the infrared absorption spectrum of acrylonitrile, and ν _C ≡ _N ( CH ₂ = CH−CN・ML _o )
is the stretching frequency of the C≡N bond in the infrared absorption spectrum of the complex of acrylonitrile and the Lewis acid ML _o , in cm ^-1 ) As a result of the research conducted by the present inventors, the scale of the Lewis acid defined in this way and There is a good correlation between the catalytic reaction rate and strong Lewis acids, i.e. △ν _C ≡ _N
It was found that the reaction rate increases when a catalyst with a large value is used. Considering that the reaction in the method of the present invention is carried out industrially, a "strong" Lewis acid that has the power to realize a sufficient reaction rate is
According to expression (1), the △ν _C ≡ _N value is 45 cm ^-1 or more.

The strong Lewis acids used in the present invention are those in the periodic table.
It is selected from metal halogen compounds of groups _A to _A , _B to _B , and groups. Specifically, _MgF2
(△ν _C ≡ _N 54cm ^-1 ), _{ScF 3} (N 55cm -1 )
_B group compounds such as ^-1 ), TiF ₃ (58 cm ^-1 ),
_B of TiCl ₄ ZrF ₄ (58 cm ^-1 ), ZrCl ₄ (57 cm ^-1 ), etc.
group compounds, V _B group compounds such as NbF ₅ (55cm ^-1 ),
Group _B compounds such as CrF ₃ (55 cm ^-1 ), MnF ₂ (53
_B group compounds such as cm ^-1 ), FeF ₃ (51 cm ^-1 ), CoF ₂
(52 cm ^-1 ), CoF ₃ (50 cm ^-1 ), etc.
ZnI ₂ (51 cm ^-1 ), ZnCl ₂ (51 cm ^-1 ), ZnF ₂ (51 cm
^-1 ), _B group compounds such as CdF ₂ (48 ^-1 ), AlCl ₃ (48 -1),
61cm ^-1 ), A compounds such as Et ₂ AlCl (55cm ^-1 ), AlF ₃ (53cm ^-1 ), _{Group A} compounds such as SnF ₂ (51cm ^-1 ),
Examples include V _A group compounds such as SbF ₃ (50 cm ^-1 ).

The amount of Lewis acid used is 0.0001 to 5 mol, preferably 0.0001 to 5 mol, per 1 mol of acrylonitrile.
It is in the range of 0.001 to 1 mole.

In carrying out the method of the present invention, there is no problem even if no reaction solvent is used, but an appropriate inert solvent may be used in order to perform the operation smoothly.

Examples of such solvents include ethers such as diethyl ether, anisole, tetrahydrofuran, ethylene glycol dimethyl ether, and dioxane, ketones such as acetone, methyl ethyl ketone, and acetophenone, methanol, ethanol, n-butanol, benzyl alcohol, phenol, and ethylene glycol. , alcohols such as diethylene glycol, carboxylic acids such as formic acid, acetic acid, propionic acid, toluic acid, esters such as methyl acetate, n-butyl acetate, benzyl benzoate, benzene, toluene, ethylbenzene,
Aromatic hydrocarbons such as tetralin, n-hexane,
Aliphatic hydrocarbons such as n-octane and cyclohexane, halogenated hydrocarbons such as dichloromethane, trichloroethane and chlorobenzene, nitro compounds such as nitromethane and nitrobenzene, N,N-
Dimethylformamide, N,N-dimethylacetamide, carboxylic acid amide such as N-methylpyrrolidone, hexamethylphosphoric acid triamide, N,N,
Other amides such as N',N'-tetraethylsulfamide, N,N'-dimethylimidazolidone,
Ureas such as N,N,N,N-tetramethylurea,
Sulfones such as dimethyl sulfone and tetramethylene sulfone, sulfoxides such as dimethyl sulfoxide and diphenyl sulfoxide, lactones such as γ-butyrolactone and ε-caprolactone, polyethers such as tetraglyme and 18-crown-6, acetonitrile, These include nitriles such as benzonitrile, carbonate esters such as dimethyl carbonate, and ethylene carbonate.

In carrying out the reaction of the method of the present invention, the reaction can be carried out either batchwise or continuously. Reaction temperature is 50~350℃, preferably 100~
Selected from the range of 250℃. The reaction pressure is not limited and is determined by selection conditions such as the reaction substrate, solvent, diluent, and reaction temperature.

The desired product, reaction raw material, and catalyst component are separated from the reaction product liquid by ordinary separation and purification means such as distillation and extraction.

〔Example〕

EXAMPLES Below, the method of 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 the gist thereof is exceeded.

Example 1 Hastelloy C276 with pressure resistance of 300Kg/cm ² and internal volume of 35ml
25 mmol of acrylonitrile in a manufactured autoclave.
Isobutylene 118 mmol, titanium tetrachloride 1.25 mmol
and 10 ml of benzene, and the reaction was carried out at 180°C for 3 hours. After the reaction was completed, the product solution was analyzed by gas chromatography, and it was found that 5-methyl-5-
It was confirmed that 1.25 mmol of hexenonitrile was produced.

Example 2 Acrylonitrile 50 mmol, isobutylene 234
mmol, titanium tetrachloride 2.5 mmol and benzene 10
As a result of carrying out the reaction for 6 hours at 180° C. in the same manner as in Example 1 using 5.10 mmol of 5-methyl-5-hexenonitrile, it was confirmed that 5.10 mmol of 5-methyl-5-hexenonitrile was produced.

Comparative example 1 Acrylonitrile 25mmol, isobutylene 87m
The autoclave was charged with 10 ml of benzene and the reaction was carried out at 180°C for 3 hours in the same manner as in Example 1 without using a catalyst. As a result, the amount of 5-methyl-5-hexenonitrile produced was 0.00 mmol. Ta.

Example 3 Acrylonitrile 50 mmol, isobutylene 219
mmol, diethyl-aluminum chloride 2.5m
mol, and at 180 °C using 16 ml of benzene.
As a result of carrying out the reaction for 3 hours in the same manner as in Example 1, 5
The production of 3.50 mmol of -methyl-5-hexenonitrile and 0.13 mmol of 5-methylenenonanedinitrile was confirmed.

Example 4 Acrylonitrile 50 mmol, isobutylene 255
mmol, diethylaluminum chloride 2.5m
mol, and at 200 °C using 16 ml of benzene.
As a result of carrying out the reaction for 5 hours in the same manner as in Example 1, 5
The production of 10.0 mmol of -methyl-5-hexenonitrile and 0.3 mmol of 5-methylenenonanedinitrile was confirmed.

Example 5 Acrylonitrile 50 mmol, isobutylene 216
mmol, diethylaluminum chloride 2.5m
mol, and at 250 °C using 16 ml of benzene.
As a result of carrying out the reaction for 3 hours in the same manner as in Example 1, 5
The production of 7.40 mmol of -methyl-5-hexenonitrile and 0.28 mmol of 5-methylenenonanedinitrile was confirmed.

Example 6 Acrylonitrile 50 mmol, isobutylene 219
mmol, diethylaluminum chloride 2.5m
mol, and at 200 °C using 16 ml of benzene.
As a result of carrying out the reaction for 12 hours in the same manner as in Example 1,
Production of 12.6 mmol of 5-methyl-5-hexenonitrile and 0.45 mmol of 5-methylenenonanedinitrile was confirmed.

Example 7 Acrylonitrile 50 mmol, isobutylene 210
mmol, diethylaluminum chloride 5.0m
mol, and using 10 ml of n-hexane, 200
As a result of carrying out the reaction at ℃ for 3 hours in the same manner as in Example 1, 9.10 m of 5-methyl-5-hexenonitrile was obtained.
mol and 5-methylenenonanedinitrile 0.23m
The production of mol was confirmed.

Example 8 Acrylonitrile 50 mmol, isobutylene 230
mmol, diethylaluminum chloride 2.5m
mol, and using 16 ml of acetonitrile,
As a result of carrying out the reaction at 200°C for 3 hours in the same manner as in Example 1, 2.50 m of 5-methyl-5-hexenonitrile was obtained.
The production of mol was confirmed.

Example 9 Acrylonitrile 50 mmol, isobutylene 225
mmol, diethylaluminum chloride 5.0m
mol, titanium tetrachloride 5.0 mmol and benzene 16 ml
The reaction was carried out at 180° C. for 3 hours in the same manner as in Example 1, and as a result, it was confirmed that 11.7 mmol of 5-methylel-5-hexenonitrile and 0.38 mmol of 5-methylenenonane dinitrile were produced.

Example 10 Acrylonitrile 50 mmol, isobutylene 228
mmol, zinc fluoride 5.0 mmol, and benzene 10
As a result of carrying out the reaction for 3 hours at 200° C. in the same manner as in Example 1, it was confirmed that 2.90 mmol of 5-methyl-5-hexenonitrile was produced.

Example 11 Acrylonitrile 50 mmol, isobutylene 212
mmol, zinc iodide 5.0 mmol, and benzene 10
As a result of carrying out the reaction for 3 hours at 200° C. in the same manner as in Example 1, it was confirmed that 4.8 mmol of 5-methyl-5-hexenonitrile and 0.23 mmol of 5-methylenenonane dinitrile were produced.

Example 12 Acrylonitrile 50 mmol, isobutylene 221
mmol, zinc chloride 5.0 mmol, and benzene 10 ml
The reaction was carried out at 200°C for 16 hours in the same manner as in Example 1, and as a result, it was confirmed that 8.20 mmol of 5-methyl-5-hexenonitrile and 0.43 mmol of 5-methylenenonane dinitrile were produced.

Example 13 Acrylonitrile 50 mmol, isobutylene 214
The reaction was carried out in the same manner as in Example 1 at 200° C. for 3 hours using 5.0 mmol of zirconium tetrachloride and 10 ml of benzene, and as a result, the production of 1.0 mmol of 5-methyl-5-hexenonitrile was confirmed.

Comparative example 2 Acrylonitrile 50mmol, isobutylene 23m
mol, boric acid (Δν _C=N value, 11cm ^-1 ), 5 mmol, and 10 ml of benzene, the reaction was carried out at 200°C for 3 hours in the same manner as in Example 1. As a result, 5-methyl-5-
The amount of hexenonitrile produced was 0.01 mmol.

[Effects of the Invention] According to the present invention, the reaction temperature and pressure conditions can be adjusted by coexisting a specific Lewis acid, which is a novel catalyst, in the reaction system of acrylonitrile and isobutylene or its derivative represented by the general formula (). It is possible to alleviate the situation to a large extent, and this is of great significance.

Claims (1)

[Claims] 1. In the presence of a Lewis acid catalyst selected from metal halogen compounds of groups _A to _A , _B to _B of the periodic table, acrylonitrile and a compound of the general formula () (wherein, R ¹ represents a methyl group or 3-cyano-propyl group) (In the formula, R ¹ is the same as defined above.) A method for producing an unsaturated nitrile compound represented by the following.