JPH0717582B2 - Process for producing alkenyl group-substituted anilines - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention is directed to catalytic dehydrogenation of alkyl group-substituted anilines,
An alkenyl group-substituted aniline useful as a raw material for the production of 2-bis (aminophenyl) propane, which is used as a pesticide raw material or a monomer for polystyrene resin having an amino group in the benzene ring, and as a resin modifier for epoxy, polyamide, etc. The manufacturing method of a class.

[Conventional technology]

As a conventional method for obtaining an alkenyl group-substituted aniline, for example, a method of cleaving a hydroxyphenyl-aminophenyl-alkane in the presence of a basic catalyst (Japanese Patent Publication No.
41-1937), a method of obtaining it from an equimolar reaction product of a carbonyl compound and a hydrochloride of an aromatic amine [Annalen der Chemie, Vol. 472, p. 11, 1
929], but the yield is not so good. As another reaction method, a method of catalytically dehydrogenating an alkyl group-substituted aniline to obtain an alkenyl group-substituted aniline is conceivable, but there has been no report so far.

[Problems to be solved by the invention]

From this viewpoint, the present inventors have studied a method of producing an alkenyl group-substituted aniline by catalytic dehydrogenation of an alkyl group-substituted aniline, and obtained the target product with high yield and high selectivity. Moreover, we have studied to develop a catalyst with a long life.

[Means and Actions for Solving Problems]

As a result, they have found that the above object can be achieved by adopting the following method, and completed the present invention. That is, according to the method of the present invention, an alkenyl group-substituted aniline characterized by catalytically dehydrogenating an alkyl group-substituted aniline in the presence of a catalyst containing iron oxide as a main component and further containing silicon oxide and chromium oxide. A method of manufacturing the same is provided.

(Catalyst)

The catalyst used in the present invention is a catalyst containing iron oxide as a main component and also containing silicon oxide and chromium oxide. In the present invention, in addition to these components such as iron oxide, if necessary, germanium oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, gallium oxide, antimony oxide, bismuth oxide, vanadium oxide,
A catalyst containing a metal oxide such as indium oxide or boron oxide can be used. Further, aluminum oxide or zirconium oxide may be contained in addition to chromium oxide for the purpose of prolonging the catalyst life. In the catalyst of the present invention, the proportion of iron oxide in the catalyst is usually 30 to 95% by weight, preferably 50 to 95% by weight, and the use of a catalyst outside this range reduces the activity for the reaction of the present invention. Is not preferred. In the catalyst of the present invention, the content ratio of iron oxide and silicon oxide is usually 0.05 to 0.45, preferably 0.075 in terms of the ratio of the number of atoms of iron and silicon (Si / Fe).
It is particularly preferable that the range is 0.25. From the viewpoint of catalyst life, the content ratio of iron oxide and chromium oxide is expressed by the ratio of the number of atoms of iron and chromium (Cr / Fe), and is usually 0.01 to 0.2.
It is particularly preferable to set it to 5, preferably 0.03 to 0.17.

As a method for preparing the catalyst of the present invention, for example, a method obtained by calcining a mixture containing at least one iron compound and other metal compounds capable of becoming the above-mentioned metal oxides at a predetermined temperature described below. Can be shown. Specific examples of the iron compound and other metal compounds include inorganic acid salts such as oxides, nitrates, hydrochlorides and sulfates of these metals, organic acid salts such as acetates and oxalates, and organic metal compounds. Examples thereof include compounds known to be capable of being converted into metal oxides by firing of metal hydroxides, metal alkoxides, and the like. More specifically, in the present invention, the compound is silicon tetrachloride, sodium silicate, germanium nitrate, germanium chloride, zirconium nitrate, zirconium chloride, titanium chloride, titanyl nitrate, magnesium nitrate, magnesium chloride, magnesium sulfate, calcium nitrate, chloride. Calcium, chromium nitrate, chromium chloride,
Inorganic acid salts such as potassium chromate, germanium acetate, magnesium acetate, magnesium oxalate, organic acid salts such as calcium oxalate, methyl magnesium chloride,
Organometallic compounds such as diethyldichlorosilane and dibenzenechromium, metal hydroxides such as silicon hydroxide, titanium hydroxide and magnesium hydroxide, ethyl orthosilicate, t
Examples thereof include metal alkoxides such as -butylalkoxyzirconium and t-butylalkoxytitanium. In the present invention, as a method for obtaining the above-mentioned mixture of metal compounds, a conventionally known method can be adopted. Specific examples of the method include a method of adding an alkali to an aqueous mixed salt solution of the metal to obtain a mixed metal hydroxide, a method of impregnating and supporting an aqueous metal salt solution of another metal, or a metal oxidation method. Examples include a method of immersing an object, a method of kneading and mixing metal oxides or metal salts. In the present invention, it is preferable to use the method of adding aqueous ammonia or an aqueous solution containing an alkali metal to the mixed salt aqueous solution.

In the present invention, the catalyst of the present invention can be obtained by calcining a mixture of the various types of metal compounds described above, and the calcining temperature is usually 400 to 100 as the condition in this case.
It is 0 ° C, preferably 500 to 700 ° C. The firing time varies depending on the firing temperature, but is usually 0.5 to 3 hours.
The firing is usually performed in the air, but it can be performed in an atmosphere of an inert gas such as titanium.

[Reaction]

In the present invention, an alkenyl group-substituted aniline is produced by reacting an alkyl group-substituted aniline in the presence of the catalyst and catalytically dehydrogenating the same.

The alkyl group-substituted anilines used as the raw material of the present invention are monovalent or polyvalent anilines having one or more alkyl groups, and one of the alkyl groups has 2 or more prime atoms, preferably one or more. The alkyl group has 2 to 6 carbon atoms, and specific examples of the alkyl group include ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, n-amyl, isoamyl, cyclohexyl and cyclopentyl groups. Can be mentioned. Specific examples of the alkyl group-substituted anilines include ethylaniline, N-methylethylaniline, N, N'-dimethylethylaniline and n-
Propylaniline, isopropylaniline, n-butylaniline, sec-butylaniline, n-pentylaniline, cyclopentylaniline, cyclohexylaniline, ethyltoluidine, ethylxylidine, diethylaniline, diisopropylaniline, isopropyltoluidine, isopropylxylidine, N-methyl Isopropylaniline, N, N'-dimethylisopropylaniline,
Examples thereof include ethyl phenylenediamine and isopropyl phenylenediamine. Among them, o-ethylaniline, m-ethylaniline, p-ethylaniline, m-
Isopropylaniline, p-isopropylaniline, m
Alkyl group-substituted anilines having an alkyl group having 2 to 4 carbon atoms such as -n-propylaniline and pn-propylaniline are preferable.

In the present invention, as the reaction conditions for carrying out the catalytic dehydrogenation reaction, the reaction temperature is usually 400 to 650 ° C, preferably 480 to 570 ° C.
In the range of, feed rate to the raw material of the catalyst layer is usually 0.05～2.0Hr ^-1 expressed as liquid hourly space velocity (LHSV), preferably in the range of 0.1~0.7hr ^-1. Further, in carrying out the reaction in the present invention, an inert gas such as titanium and / or steam, benzene, toluene, hexane, n-octane,
A diluent such as n-decane can also be used if necessary. When a diluent is added, the diluent is usually used in an amount of 3 to 50 times, preferably 10 to 30 times the mol of the reaction raw material. When a diluent is added, the selectivity of the desired alkenyl group-substituted anilines can be improved, and the life of the catalyst can be extended, which is preferable.

In the present invention, the reaction is usually carried out by a catalyst flow system, and the catalyst bed used may be a fixed bed, a moving bed, a fluidized bed, or the like.

The alkenyl group-substituted anilines obtained by the method of the present invention correspond to the starting alkyl group-substituted anilines, and specifically, ethenylaniline, isopropenylaniline, 1-propenylaniline, 1-butenylaniline. , Ethenyltoluidine, ethenylxylidine, N-methylethenylaniline, cyclopentylaniline, cyclohexylaniline, ethenylphenylenediamine and the like.

〔The invention's effect〕

According to the method of the present invention, alkenyl group-substituted anilines can be obtained in high yield and high selectivity.

〔Example〕

Hereinafter, the method of the present invention will be specifically described with reference to Examples.

Was dissolved Example 1 ferric nitrate _{[Fe (NO 3) 3 · 9H} 2 O ] 303g and chromium nitrate _{[Cr (NO 3) 3 · 9H} 2 0 ] 12.8g of about 3 distilled water, further Nissan Chemical 20wt% silica sol 20.6 manufactured by Co., Ltd.
g was added and mixed well. To this solution, 250 ml of about 25% by weight of commercially available aqueous ammonia was stirred at room temperature with vigorous stirring for 2-3
Added in minutes. The pH of the solution was 10.5. After the stirring was continued for about 5 minutes, the resulting dark brown slurry was washed by repeating decantation and filtration, and the cake obtained was dried in a dryer at about 90 ° C. for 20 hours. Furthermore, this cake was baked in the air at 650 ° C. for 3 hours.

When the composition of the composite oxide thus obtained was measured by atomic absorption spectrometry, it was found that the atomic ratio was Fe: Si: Cr = 87: 9: 4.
Agglomerate catalyst is crushed into 20 to 32 mesh, sieved to 20 ml
Was charged into an ordinary quartz reaction tube having an inner diameter of 30 mmφ. The temperature of the catalyst bed was set to 560 ° C, and m-isopropylaniline and water were quantitatively supplied to the catalyst bed via a preheated vaporization mixer kept at about 330 ° C, and passed through the catalyst layer. At this time, the liquid hourly space velocity (LHSV) was 0.3 hr ⁻¹ with respect to m-isopropylaniline, while the water LHSV was 0.4 hr ⁻¹ . The reaction product is analyzed by gas chromatography,
The conversion of the raw material m-isopropylaniline and the selectivity of the product were determined. Table 1 shows the results when a steady reaction result was obtained by continuing the reaction for about 5 hours.

Example 2 A metal consisting of elements of Fe, Si, Ca and Cr was all prepared in the same manner as in Example 1 except that silica sol was added in the catalyst preparation of Example 1 and then calcium hydroxide powder was further added and mixed. An oxide catalyst was prepared. This composition is in atomic%
Fe: Si: Ca: Cr = 84: 8: 4: 4.

Using this catalyst, the dehydrogenation reaction of 6-methyl-3-isopropylaniline was carried out according to Example 1. The results are shown in Table 2.
Shown in.

Was dissolved Example 3 ferric sulfate _{[Fe (NO 3) 3 · 9H} 2 O ] 303g and chromium nitrate _{[Cr (NO 3) 3 · 9H} 2 O ] 19.2g of about 4 distilled water, to which, While stirring well, commercially available ammonia water (approx.
25%) was added until the pH of the solution was 10. After stirring was continued for about 10 minutes, the generated precipitate was filtered and washed. This gel cake was kneaded with 7 g of commercially available powdered bismuth oxide Bi ₂ O _{3 and} 8.7 g of 20 wt% silica sol manufactured by Nissan Chemical Industries, Ltd. for about 30 minutes using a biaxial ribbon type kneader. Like Example 1, it was dried at 90 ° C. and then calcined at 650 ° C. for 3 hours. The composition of the obtained mixed metal oxide was Fe: Bi: Cr: Si in atomic ratio%.
= 83: 7: 6: 4. Using this catalyst, dehydrogenation of p-ethylaniline was performed. The results are shown in Table 3.

Comparative Example Copper oxide-zinc oxide (N-211) pellets manufactured by JGC Chemical Co., Ltd. were pulverized, sieved to 20 to 32 mesh, filled in a reaction tube, and treated with m-isopropylaniline in the same manner as in Example 1. A dehydrogenation reaction was performed. The results are shown in Table 4.

Claims (1)

[Claims] 1. A process for producing an alkenyl group-substituted aniline, which comprises catalytically dehydrogenating an alkyl group-substituted aniline in the presence of a catalyst containing iron oxide as a main component and also containing silicon oxide and chromium oxide.