JPH02142762A - Production of dicyanocyclohexanes - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high efficiency and yield on an industrial scale at a low cost by cyanohydrogenating 4-cyanocyclohexene in the presence of a zero-valent nickel complex and a cocatalyst at a specific molar ratio to the nickel complex under a specific reaction condition and subjecting the reaction liquid to fractional distillation. CONSTITUTION:Dicyanocyclohexanes can be produced by (1) cyanohydrogenating 4-cyanocyclohexene with hydrogen cyanide in the presence of (A) a zero-valent nickel complex of e.g., formula I {A, B, C and D are neutral ligand of formula II [P is phosphorus; x, y and z are group of formula OR (R is <=18C alkyl or <=18C aryl)]} and (B) 0.05-50mol (based on 1mol of the complex A) of a cocatalyst (e. g., Zn, cadmium or beryllium) and (2) subjecting the reaction liquid to fractional distillation. The molar ratios of 4-cyanocyclohexene and hydrogen cyanide to the zero-valent nickel complex are 15-2,000 and 0.50-1.20, respectively. The reaction is carried out by charging 1-32mol of the neutral ligand based on 1mol of the complex and feeding hydrogen cyanide at a rate of 10-120mol/hr based on said complex.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing dicyanocyclohexane (hereinafter abbreviated as DCH).

More specifically, 4-cyanocyclohexene (hereinafter CC
Abbreviated as H. This invention relates to an industrially economical method for producing CHs by hydrogenating cyanide) in a liquid phase under specific catalysts and reaction conditions, and fractional distillation of the reaction solution.

[Conventional technology]

Conventionally, methods for producing DCHs include: (1) obtaining the corresponding 1,4-dicyanocyclohexane (hereinafter abbreviated as 1,4-DCII) by dehydrating hexahydroterephthalic acid diamide (Bericbte, vol.
71. No. 1,762 (1938)) is known. In addition, ■ CC) I was prepared in an acetonitrile solvent at a concentration of 53% and tetrakis(triphenylphosphite) was prepared.
Using nickel (Ni(P(OPh)3)4) and zinc chloride (ZnCE2) catalysts, CCH:Ni(P(
OPh)3) a:ZnCj! z=100:1.0:5
．． There is only a known method for hydrogen cyanation under conditions of 0 (tisP-3496217).

[Problem to be solved by the invention]

The diamide dehydration method (1) above uses a large amount of expensive thionyl chloride, and is therefore not preferred as an industrial production method. In addition, the hydrogen cyanation method (2) uses hydrogen cyanide at a molar ratio of about 1.5 times that of ccH, and is industrially uneconomical because it uses a large amount of expensive nickel complex. Furthermore, as a result of additional tests, no reproducibility was obtained.

As described above, it has not been possible to efficiently obtain DCH industrially using conventional methods.

[Means and effects for solving the yA problem] The present inventors have solved the problem by applying the cocatalyst and CCH to the charged zerovalent nickel complex in the presence of the cocatalyst in an industrially efficient and economically advanced amount. molar ratio 0.05-50 and 150-2000
range, the molar ratio of hydrogen cyanide to CCH is 0.
50 to 1.20, the solvent is 0.4 weight ratio or less to CCH, hydrogen cyanide is supplied at a hydrogen cyanide supply rate of 10 to 120 molar ratio/hour to the charged zerovalent nickel complex, and then the reaction is carried out. This is a method for producing type DC) I, which is characterized by carrying out fractional distillation of a liquid.

The present invention will be explained in detail below.

The CCH used in the present invention is a purified CCH that can be easily obtained in high yield by a Diels-Alder reaction in which acrylonitrile and butadiene are heated and reacted.

For example, it can be easily obtained by using acrylonitrile in a molar ratio of 1 to 2 to butadiene and reacting at a reaction temperature of 50 to 200°C.

In addition, the zero-valent nickel complex used in the present invention has the general formula (1).
As a result of intensive research on the hydrogen cyanation method of 13-dicyanocyclohexane (hereinafter abbreviated as 1.3-DCH).

) has been found to be able to be industrially produced in high yield, leading to the completion of the present invention.

That is, in the present invention, when hydrogenating CC)l in a liquid phase, a zerovalent nickel complex represented by the general formula (1) % formula % (1) (wherein A, B, C, D
may be the same or different general formula (n
) P(x) (y) (z) (I
I ), P is a phosphorus atom, x,
y, z shall be represented by the formula OR, and R has 1 carbon number.
It is selected from the group consisting of an alkyl group having 8 or less carbon atoms and an aryl group having 18 or less carbon atoms. ) and prompt a reaction.
(Represented by (A) (B) (c) (D): (1).

In the formula, A, B, C, and D may be the same or different. General formula (It)P(x)(i(z)
(U) represents a neutral ligand, P is a phosphorus atom, x, y, z are represented by 2OR,
R: represents a group selected from the group consisting of an alkyl group having 18 or less carbon atoms and an aryl group having 18 or less carbon atoms.

Examples of neutral ligands include triphenyl phosphite, tri(m- and p-chlorophenyl) phosphite, tri(m- and p-methoxyphenyl) phosphite, and tri(1- and p-cresyl) phosphite. Triarylphosphites and triethyl phosphites such as phite,
These are trialkyl phosphites such as triisopropyl phosphite and tributyl phosphite, and mixtures thereof.

Neutral ligands are also an important factor in controlling the cis/trans ratio of 1.4-OCR. For example, by changing from aryl phosphite to trialkyl phosphite, it is possible to increase the cis/trans ratio from 3 to 2 to around 1.

Under many reaction conditions, one or more of A, B, C, and D may be released from the zerovalent nickel complex.

Furthermore, in the present invention, the presence of a certain type of neutral ligand in excess relative to the zero-valent nickel complex increases catalyst activity and catalyst life. A suitable excess of neutral ligands is at least 1 molar ratio, preferably 2 to 32 molar ratios, more preferably 4 to 16 molar ratios, based on the zerovalent nickel complex present.
used in a range of molar ratios. Even if the molar ratio exceeds 32, there is no problem with the reaction, but it is economically unfavorable because it may lead to loss of neutral ligand recovery during purification of the reaction solution.

The manufacturing method of zero-valent nickel complex is Inorganic
5ynthesis (vol 13.P108orP1
12).

The metal acid catalyst co-catalyst used in the present invention includes zinc, cadmium, helium, aluminum, gallium, indium, silver, titanium, zirconium, hafnium,
The amount of germanium, tin, vanadium, niobium, scandium, chromium, and moly solvent used is 1.4-DC of the product DCH! (This is a very important factor in controlling the composition ratio of cis and trans isomers and extending the catalyst life.

When the amount of solvent is 0.4 weight ratio or more to CCH, 1.4-
DCH is produced in a molar ratio of 4 to 6 in the cis form/trans form, but can be produced in a molar ratio of 2 to 3 in the cis form/trans form at a weight ratio of 0.4 or less.

On the other hand, 1.3-DCH has cis form/
The change in the composition ratio of the trans isomer is in the range of about 20%, and is small and generally in the range of 0.30 to 0.40 molar ratio.

The type of solvent used is, for example, one having at least one hydroxyl group and having 6 to 20 carbon atoms, preferably 6
~10 aryl compounds, optionally fluorine, chlorine, bromine, iodine, nitro, cyano and 1 carbon atom
The above-mentioned aryl compound has one or more substituents selected from the group consisting of -6 hydrocarbon groups. For example, compounds with metal cations selected from the group consisting of phenol, P-cresol, resorcinol, β-naphthol, budene, tungsten, manganese, rhenium, palladium, thorium, erbium, iron, cobalt and mixtures thereof.

The anionic portion of the cocatalyst compound is, for example, a halogen anion such as chlorine, bromine, fluorine, and iodine;
~7 lower fatty acid anions, HPO3,) 1. Po□
−2CFsCOO−, 0SO2CJ+s− and SO.

etc. Organometallic compounds such as (cJs) 3A 42 Cl 3 and Czlls Az cp2 can also be used.

Particularly preferred metal cations are zinc, aluminum and tin. In addition, as anions, chlorine, iodine, HPO
3-'', H2POz-, etc. are particularly preferred.

The co-catalyst has the effect of extending the life of the catalyst, and the amount of co-catalyst used is 0.05% based on the zero-valent nickel complex.
-50 molar ratio, preferably 1-10 molar ratio.

In hydrogen cyanation, the neutral ligand also plays the role of a solvent, but there is no problem in using another solvent in addition to this.

p-chlorophenol, p-nitrophenol, p-phthylphenol and similar compounds. Other solvents include, for example, aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; nitriles such as acetonitrile and hendinitrile; dioxane, 0-dimethoxybenzene, tetrahydrofuran, dimethoxyethane,
Ethers such as jetoxyethane; chloroaromatic hydrocarbons such as 0-dichlorobenzene, I-dichlorobenzene, p-dichlorobenzene, and similar compounds.

Hydrocyanation of CCH in the present invention is carried out by introducing hydrogen cyanide gas into a reactor containing predetermined amounts of the above zero-valent nickel complex, promoter, CCII, and solvent.
It is carried out by contacting with a reaction solution.

Hydrogen cyanide gas can be used as it is, but from the viewpoint of handling, it is better to use an inert gas such as nitrogen, helium, or argon as a diluent gas.

Hydrogen cyanide is usually introduced as a gas into the reaction liquid in the reactor, but the reaction proceeds equally well when it is introduced into the space above the reaction liquid.

The amount of hydrogen cyanide used is CC) + 4, and usually
0.50-1.20 molar ratio, preferably 0.70-1.
A range of 0.00 molar ratio is best, and it is also preferable to introduce these amounts into the reactor in a range of 10 to 120 molar ratio/hour relative to the nickel complex. If the molar ratio is less than 1 O / hour, it will take time to obtain a high conversion of CC)I;
If the molar ratio exceeds 20 molar ratio/hour, the zero-valent nickel complex catalyst will be rapidly deactivated due to excess hydrogen cyanide.

In the present invention, by setting the supply rate of hydrogen cyanide within the above-mentioned range, it is possible to reduce the amount of hydrogen cyanide used to the minimum necessary amount, and it is possible to sustain the catalytic reaction very successfully.

In addition, the reaction temperature for hydrogen cyanation of CCH is usually 3
The temperature range is preferably 0 to 120°C, preferably 50 to 100°C, and particularly preferably 65 to 100°C. (reaction temperature (reaction temperature)), tetrakis(triphenylphosphite) nickel 0.6g (0.46 mmol), zinc chloride 0°3
g (2.2 mmol) triphenylphosphite 2.4
The contents of the reactor were kept at 75°C under stirring, and hydrogen cyanide gas diluted with nitrogen at a concentration of 42 mol% was added to the reactor at a rate of 17.7 mmol/hour. Time supplied.

Thereafter, the reaction solution was cooled and analyzed. The results are shown in Table 1.

Example 2.3 In Example 1, hydrogen cyanide gas was supplied at a rate of 35.4 mmol/hour for 4.6 hours Example 2) and 50
．． Feed for 3.1 hours at a rate of 6 mmol/hour (Example 3
) The reaction was carried out in the same manner as in Example 1, except for the following. The results are shown in Table 1.

Example 4 Same as Example 1 except that the reaction temperature was 95°C, triphenyl phosphite 1.2 g (3.9 mmol), and hydrogen cyanide gas was supplied at a rate of 19.6 mmol/hour. Exactly the same preparation and the same temperature at 30°C
Below 12, the catalytic reaction rate gradually slows down;
When the temperature exceeds 0°C, CCH decomposition etc. gradually occur.

The hydrogen cyanation reaction of CC)I is usually preferably carried out under normal pressure, and can also be carried out under pressure, but this does not produce particularly significant effects.

The reaction completion liquid of the hydrocyanation reaction is purified by fractional distillation to obtain the target products L 4-DCH and 1.3-DCH.
It is obtained as DCH containing.

As a pretreatment for fractional distillation, a known technique such as a solvent extraction method for the purpose of recovering catalytic active components and the like is used.

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

The reaction solution was analyzed by gas chromatography.

Example 1 50m equipped with stirrer, thermometer, gas introduction pipe, cooler, etc.
! In a glass round bottom flask, 18.8 g (176 g) of CCH was reacted. The results are shown in Table 1.

Comparative Example 1 A reaction was carried out in the same manner as in Example 1, except that the reaction temperature was 95°C and hydrogen cyanide was supplied at a rate of 60.3 mmol/hour for 2.6 hours. Ta. The results are shown in Table 1.

Example 5 Example 4 was exactly the same as Example 4 except that 0.3 g (0.23 mmol) of tetrakis(triphenylphosphite) nickel and 2.4 g (7.7 mmol) of triphenylphosphite were used. The reaction was carried out in the same manner. The results are shown in Table 1.

Examples 6 and 7 The materials were prepared and reacted in the same manner as in Example 1, except that the amount of toluene solvent shown in Table 1 was added. The results are shown in Table 1.

Comparative Example 2 A reaction was carried out in the same manner as in Example 1, except that the toluene solvent was further used at a weight ratio of 0.5 to CC)l. The results are shown in Table 1.

Comparative Example 3 In Example 7, the reaction was carried out in the same manner as in Example 7 except that triphenyl phosphite was not added. The results are shown in Table 1.

Example 8 In Example 4, the reaction was carried out in the same manner as in Example 4, except that ethylene glycol dimethyl ether was used at a weight ratio of 0.3 to CCI. The results are shown in Table 1.

Example 9 In Example 4, a zerovalent nickel complex was prepared by tetrakis(
Tri p-tolylphosphite) nickel 0.46 mmol, neutral ligand tri p-) tolylphosphite 3.
The reaction was carried out in the same manner as in Example 4, except that the amount was changed to 9 mmol. The results are shown in Table 1.

Example 10 In Example 4, a zerovalent nickel complex was prepared by tetrakis(
triethyl phosphite) nickel 0.46 mmol,
The reaction was carried out in exactly the same manner as in Example 4, except that the neutral ligand was changed to 9.2 mmol of triethyl phosphite. The results are shown in Table 1.

(Hereinafter, blank space) [Effects of the Invention] According to the method of the present invention, by using specific zerovalent nickel bodies, cocatalysts, and specific reaction conditions, 1.4
-DCI (and DCHs including 1.3-DCH) can be produced in high yield.Furthermore, the cis/trans isomer ratio of 1.4-DCH can be freely controlled within the range of 1 to 3. This is a novel method for producing CHH that is industrially, efficiently, and economically superior.

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A method for producing dicyanocyclohexanes by hydrocyanation of 4-cyanocyclohexene, comprising: (a) in the presence of a zerovalent nickel complex and a cocatalyst; (b)
The molar ratio of cocatalyst to zero-valent nickel complex is 0.05.
(c) The molar ratio of 4-cyanocyclohexene to the zerovalent nickel complex is in the range of 150 to 2000, (d) The molar ratio of the neutral ligand to the zerovalent nickel complex is 1 to 32. (e) The molar ratio of hydrogen cyanide to 4-cyanocyclohexene is in the range of 0.50 to 1.20, (f) The hydrogen cyanide supply rate is in the range of 10 to 120 molar ratio/hour to the charged zerovalent nickel complex. (g) A method for producing dicyanocyclohexanes, which comprises hydrogenating the solvent at a weight ratio of 0.4 or less to 4-cyanocyclohexene, and then fractionally distilling the reaction solution. 2. The method according to claim 1, wherein the zero-valent nickel complex is tetrakis(trialkylphosphite)nickel. 3. The method according to claim 1 or 2, wherein the solvent is an ether.