JP2936726B2 - Method for producing aromatic amine compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an aromatic amine compound from an aromatic nitro compound using carbon monoxide and water.

[0002]

BACKGROUND ART Aromatic amine compounds such as aniline are industrially important compounds as pharmaceuticals, agricultural chemicals, dyes, pigments and intermediates thereof.

A method for producing an aromatic amine compound includes the following:
Methods for reducing aromatic nitro compounds using a catalyst in a carbon monoxide / water system include, for example, (1) Journal of
American Chemical Society (J.Am.Chem.So
c., 100 , 3969 (1978)) describes an example in which nitrobenzene is produced in a mixed solvent of aqueous tetrahydrofuran-trimethylamine in the presence of a rhodium or ruthenium catalyst.

[0004] Also, (2) EP-A-0 097 592 discloses that nitrobenzene is prepared by adding 3,4,7,8-tetramethyl-1,10-phenanthroline to an ethanol solvent in the presence of a rhodium or ruthenium catalyst. An example of producing nitrotoluene and the like is described.

[0005]

However, in these prior arts, it is difficult to say that the activity of the catalyst is sufficient, and it is necessary to increase the concentration of the catalyst or to react at a high temperature and a high pressure for a long time.

[0006] In yet method (1) had to be present in quite large amounts (10 ³ times with respect to ruthenium metal) of trimethylamine.

In this method, the American Chemical Society Symposium series (AC.
S., Symp. Ser., 152 , 325 (1981)), this catalyst system produces hydrogen and carbon dioxide from water and carbon monoxide, a so-called water gas shift reaction.
As described in (1), a large amount of hydrogen is produced as a by-product in the reaction system, and water and carbon monoxide are also generated in a large amount in addition to the reduction reaction of the nitro group, as described in (1). There was a problem that it was consumed.

In the above method (2), only compounds having an inert substituent such as an alkyl group, an alkoxy group or an amino group are effective as nitro compounds.
The applicable nitro compounds were limited. Journal of Molecular Catalysis (J. Mol. Catal. , 22,327
(1984)) describes that a catalyst system containing rhodium as a central metal reduces not only olefins but also carbonyl groups in the reduction reaction of benzylideneacetone.

[0009]

Means for Solving the Problems In view of such circumstances, the present inventors have studied the use of aromatic nitro compounds (nitroanthraquinones) using carbon monoxide and water in the presence of a homogeneous catalyst comprising a ruthenium compound and a solvent. ), The result of studying the method for producing an aromatic amine compound from a water gas shift reaction was demonstrated by the coexistence of certain amines, in which only the nitro group was reduced to the selected enemy, and while exhibiting high catalytic activity. It has been found that such a side reaction does not proceed, and the present invention has been completed.

That is, the present invention produces an aromatic amine compound from an aromatic nitro compound (excluding nitroanthraquinones) using carbon monoxide and water in the presence of a homogeneous catalyst comprising a ruthenium compound and a solvent. In the method, amines represented by the general formula (I) HNR ¹ R ² (I) (wherein R ¹ and R ² are each hydrogen, an alkyl group which may have a substituent, or a substituent. A cycloalkyl group, an aralkyl group, or an aryl group which may have a substituent, wherein R ¹ and R ² are not hydrogen at the same time, and R ¹ and R ² together form a ring And a method for producing an aromatic amine compound.

Hereinafter, the present invention will be described in detail.

The reaction in the present invention uses carbon monoxide / water as a hydrogen source.

The aromatic nitro compound used in the present invention includes a compound having at least one nitro group in an aromatic ring. Examples of the aromatic ring include hydrocarbon aromatic rings such as benzene, naphthalene, and anthracene, and heteroaromatic rings such as pyridine and quinoline. further,
These aromatic nitro compounds include, in addition to nitro groups, alkyl groups, halogen groups, amino groups, hydroxyl groups, carbonyl groups,
Substituents such as an alkoxy group, a cyano group and a sulfone group may be bonded. Commonly used aromatic nitro compounds include nitrobenzene, o-nitrotoluene, m-nitrotoluene, p-nitrotoluene, 2-nitro-p-
Xylene, o-chloronitrobenzene, m-chloronitrobenzene, p-chloronitrobenzene, p-cyanonitrobenzene, o-nitroaniline, m-nitroaniline, p-nitroaniline, o-dinitrobenzene, m-
Dinitrobenzene, p-dinitrobenzene, 2,4-dinitrotoluene, o-nitrophenol, m-nitrophenol, p-nitrophenol, o-nitroanisole, m-nitroanisole, p-nitroanisole, α
-Nitronaphthalene, β-nitronaphthalene, 2'-nitroacetophenone, 3'-nitroacetophenone,
-Nitrobenzophenone, 4-nitrobenzophenone,
4-nitroimidazole, o-nitrobenzonitrile,
m-nitrobenzonitrile, p-nitrobenzonitrile, o-nitrobenzenesulfonic acid, m-nitrobenzenesulfonic acid, p-nitrobenzenesulfonic acid, o-nitrobenzenesulfonamide, m-nitrobenzenesulfonamide, p-nitrobenzenesulfonamide, o-
(Β-hydroxyethylsulfonyl) nitrobenzene,
m- (β-hydroxyethylsulfonyl) nitrobenzene, p- (β-hydroxyethylsulfonyl) nitrobenzene and the like.

The homogeneous catalyst used in the present invention refers to a catalyst in which the catalyst is partially or entirely dissolved in a solvent.

The catalyst used in the present invention is a ruthenium compound, and is preferably a complex having a carbonyl ligand or a compound which easily forms a carbonyl complex under reaction conditions.

For example, those which form a carbonyl complex under the reaction conditions include carbonyl compounds, salts such as acetylacetonate salts, carboxylate salts, oxides, hydroxides, halides, nitrates and phosphates. Compounds.

Specifically, as the catalyst, Ru ₃ (CO)
₁₂ , H ₄ Ru ₄ (CO) ₁₂ , Ru (acac) ₃ , RuCl ₃ , (RuCl ₂ (COD)) _n , (R
uCl ₂ (CO) ₃ ) ₂ , RuO ₂ , Ru (CF ₃ COCH ₂ COCF ₃ ) ₃ , RuH (OAc) (PP
h ₃ ) ₃ , Ru (CO) ₅ , RuH ₂ (PPh ₃ ) ₄ , RuCl ₂ (PPh ₃ ) ₄ , RuHCl (PP
h ₃ ) ₄ , RuCl ₃ , RuBr ₃ , RuI ₃ , Ru (NO) (NO ₃ ) ₃ , Ru (NO) Cl ₃ , H ₃ Ru
(SO ₃ ) ₂ OH, RuCl ₂ (CO) ₂ (PPh) ₃ ) _{2 and the} like. Note that acac represents acetylacetonate, and COD represents 1,5-cyclooctadiene.

Of these, Ru ₃ (CO) ₁₂ is particularly preferred as the catalyst.

The amount of the catalyst used in the present invention varies depending on the reaction conditions and the like, but is usually about 10 ^-1 to 10 ^-5 mol or less per mol of the substrate.

In the present invention, a suitable solvent is present. Examples of the catalyst used in the present invention include alcohol solvents such as methanol, ethanol, isopropyl alcohol, normal propyl alcohol, normal butyl alcohol, isobutyl alcohol, normal pentyl alcohol, isoamyl alcohol and tert-amyl alcohol;
Diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, ethylene glycol, diethylene glycol, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol monoethyl ether acetate, etc. Grime solvent, tetrahydrofuran, 1,4-
Examples include ether solvents such as dioxane and anisole, and ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. Among them, methanol,
Ethanol, isopropyl alcohol, normal butyl alcohol, diethylene glycol dimethyl ether,
Triethylene glycol dimethyl ether and acetone are preferred. Further, methanol, ethanol, diethylene glycol dimethyl ether and acetone are more preferred.

The amines used in the present invention include those represented by the general formula (I). NHR ¹ R ² (I)

In the formula, R ¹ and R ² each represent hydrogen, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an aralkyl group, or an aryl group which may have a substituent; R ¹ and R ² are not hydrogen at the same time. Here, as the substituent, an alkyl group,
Examples include a halogen group, a hydroxyl group, and an alkoxy group. Examples of R ¹ and R ² which together form a ring include-(CH) ₄ -,-(CH ₂ ) ₄ -,-(CH ₂ ) ₅ -,-
(CH ₂ ) ₂ —NH— (CH ₂ ) ₂ — and the like.

Examples of the amines include methylamine, ethylamine, normal propylamine, isopropylamine, normal butylamine, isobutylamine, tert-butylamine, normal pentylamine, normal hexylamine, normal heptylamine, normal octylamine and dimethylamine. , Diethylamine, dinormalpropylamine, diisopropylamine, dinormalbutylamine, diisobutylamine, dinormalpentylamine, dinormalhexylamine,
Dinormal heptylamine, dinormal octylamine, ethyl isopropylamine, 3-dimethylaminopropanol, 2-aminopropanol, 2-ethylhexylamine, 3-methoxypropylamine, 3-ethoxypropylamine, 2-chloroethylamine, bis-
(2-Chloroethyl) amine, 3-chloroethylamine and the like, which may have a substituent, may be a C1-8 alkyl group, a substituent such as cyclohexylamine, cyclopentylamine, dicyclohexylamine, and 2,3-dimethylcyclohexylamine. Cycloalkyl groups having 5 to 6 carbon atoms, aralkyl groups such as benzylamine, dibenzylamine, N-benzylmethylamine and N-benzylethanolamine, which may be present, aniline, diphenylamine, o-toluidine, m-toluidine, p -Toluidine, o-chloroaniline, m-chloroaniline, p-chloroaniline, o-anisidine, m-anisidine, p-
Aryl groups which may have a substituent such as anisidine, o-aminophenol, m-aminophenol, p-aminophenol, pyrrole, pyrrolidine, piperidine,
And cyclic amines such as piperazine.

Among the amines used in the present invention, diethylamine, diisopropylamine, di-n-butylamine, normal-butylamine, pyrrolidine,
Piperidine, piperazine, dicyclohexylamine, benzylamine, o-chloroaniline are preferred.

The above amines are usually used in a molar amount of 0.01 to 500 times, more preferably 0.01 to 1 times, per mol of the catalytic metal.
It is used in a molar amount of 00 times.

The reaction temperature of the present invention is usually in the range of 0 to 250 ° C., preferably 100 to 200 ° C. The activity is improved by increasing the reaction temperature. The pressure of CO used in the present invention is not particularly limited, but may be usually 1 to 100 atm or more.

[0027]

As described in detail above, the present invention has a remarkable catalytic activity and reduces only the nitro group with very high selectivity. , And in a high yield. Further, in the present invention, the reduction reaction of the nitro group proceeds preferentially without the side reaction such as the water gas shift reaction proceeding.

[0028]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The stainless steel magnetic stirring type autoclave of Examples 1 to 5 internal volume _{50cc, Ru 3 (CO) 12} (0.003mmol), ethanol (5 ml), water (2 ml), the amine shown in Table 1 and nitrobenzene (about 5
mmol), the mixture was stirred under the conditions of a CO pressure of 20 kg / cm ² and a reaction temperature of 150 ° C., and the reaction was performed for 100 minutes.

The reaction product was quantitatively analyzed by gas chromatography, and its identification was performed by comparing the retention times of gas chromatograms and by using GC-MS.

The following total turnover number (TN) was used as an index indicating the activity of the catalyst. Total turnover number (TN) = Amount of aniline formed (mmol) / Amount of catalyst (mmol)

As a result of analysis, the product was only aniline, and there were no other by-products. Table 1 shows the results.

The following examples and comparative examples were also analyzed in the same manner.

Comparative Example 1 The reaction was carried out under the same conditions as in Example 1 except that 3,4,7,8-tetramethyl-1,10-phenanthroline (0.0045 mmol) was used as the amine.

Analysis revealed that the product was only aniline and no other by-products.

The results are shown in Table 1.

Examples 6 to 12 Using ethanol (10 ml) and water (4 ml) as solvents,
The reaction was carried out under the same conditions as in Example 1 except that about 10 mmol of nitrobenzene was added and the amines shown in Table 2 were used.

Analysis revealed that the product was only aniline and no other by-products. Table 2 shows the results.

Examples 13 to 15 The reaction was carried out under the same conditions as in Example 6 except that the amine shown in Table 3 was used and the reaction temperature was set at 180 ° C.

Analysis revealed that the product was only aniline and no other by-products.

Table 3 shows the results.

Examples 16 to 19 The reaction was carried out under the same conditions as in Example 9 except that the solvents shown in Table 4 were used.

As a result of analysis, the product was only aniline, and there were no other by-products.

Table 4 shows the results.

Example 20 Ru ₃ (CO) ₁₂ (0.0
1 mmol), diisopropylamine (1.5 mmol), diethylene glycol dimethyl ether (15 ml), water (5 ml) and o-chloronitrobenzene (5 mmol), and the mixture was stirred at a CO pressure of 20 kg / cm ² and a reaction temperature of 150 ° C.
A time reaction was performed.

After completion of the reaction, the product was analyzed as o-
Only chloraniline (yield 99% or more) without other by-products.

After the completion of the reaction, the substance composition in the gas phase is H ₂
0.4 mmol, 72.3 mmol of CO, and 14.7 mmol of CO ₂ .

Example 21 A reaction was carried out under the same conditions as in Example 20 except that a 50 cc magnetic stirring autoclave was used and o-bromonitrobenzene was used instead of o-chloronitrobenzene.

After the reaction, an analysis revealed that the product was only o-bromoaniline (yield 99% or more), and there was no other by-product.

Example 22 A reaction was carried out under the same conditions as in Example 21 except that p-chloronitrobenzene was used instead of o-bromonitrobenzene.

After the reaction, analysis revealed that the product was only p-chloroaniline (yield 99% or more) and no other by-products.

Example 23 A reaction was carried out under the same conditions as in Example 21 except that p-cyanonitrobenzene was used instead of o-bromonitrobenzene.

After the reaction, analysis revealed that the product was only p-aminobenzonitrile (yield 99% or more) and no other by-products.

Example 24 A reaction was carried out under the same conditions as in Example 21 except that p-nitrobenzophenone was used instead of o-bromonitrobenzene.

After the reaction, analysis revealed that the product was only p-aminobenzophenone (99% or more yield) and no other by-products.

Comparative Example 2 A reaction was carried out under the same conditions as in Example 21 except that acetophenone was used instead of o-bromonitrobenzene.

After the reaction, as a result of analysis, no product was confirmed, and only acetophenone was recovered.

Comparative Example 3 A reaction was carried out under the same conditions as in Example 21 except that phenylacetylene was used instead of o-bromonitrobenzene.

After the reaction, as a result of analysis, no product was confirmed, and only phenylacetylene was recovered.

Comparative Example 4 A reaction was carried out under the same conditions as in Example 20 except that benzonitrile was used instead of o-chloronitrobenzene.

After the reaction, as a result of analysis, no product was confirmed, and only benzonitrile was recovered.

After the completion of the reaction, the substance composition in the gas phase is H ₂ 0.4
mmol, CO 94.9 mmol, and no CO ₂ was detected.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 225/22 C07C 225/22 253/30 253/30 255/58 255/58 // C07B 61/00 300 C07B 61/00 300

Claims (1)

(57) [Claims] 1. A method for producing an aromatic amine compound from an aromatic nitro compound (excluding nitroanthraquinones) using carbon monoxide and water in the presence of a homogeneous catalyst comprising a ruthenium compound and a solvent, Amines represented by the general formula (I) HNR ¹ R ² (I) (wherein R ¹ and R ² are each hydrogen, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent , An aralkyl group or an aryl group which may have a substituent, wherein R ¹ and R ² are not hydrogen at the same time, and R ¹ and R ² may together form a ring. ) In the coexistence of an aromatic amine compound.