JPS5826907B2 - Method for producing benzophenoneazines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing benzophenoneazines (hereinafter abbreviated as azines) from benzophenone imines (hereinafter abbreviated as imines).

Azines are extremely useful substances as intermediates in hydrazine synthesis reactions using benzophenones as starting materials.

The method for producing azines by oxidizing imines is as follows:
A method using molecular oxygen in the presence of cuprous chloride is known (USP-2870206).

However, since this method uses an expensive copper salt catalyst as a liquid-phase homogeneous catalyst, it requires complicated steps of catalyst separation, recovery, and regeneration, resulting in increased equipment costs and energy loss. .

Furthermore, due to the problem of corrosion caused by halogen substances, expensive materials are required, and this method cannot be said to be industrially advantageous.

The present invention has been made as a result of investigating various methods for industrially producing azines by eliminating the above-mentioned drawbacks.The present invention has revealed that metal oxides are useful substances as catalysts for producing azines from imines. This study was completed based on this finding.

That is, the present invention relates to a compound of the general formula (in which R1 and R2 may be the same or different, a chain type, cycloaliphatic or aromatic hydrocarbon group having 1 to 10 carbon atoms, an ether group thereof, or an acyl group). group, acyloxy group, alkoxycarbonyl group, halogen, hydroxy, nitro, amido, cyano, a group selected from the group consisting of trisubstituted amino group, or R1 and R2 together represent a single bond or group; It's okay.

m%n is 0 or an integer from 1 to 5.

A compound represented by the general formula (in which R1, R2, m, and n are the same as in general formula (I)) is characterized in that the benzophenone imine represented by is brought into contact with molecular oxygen in the presence of a metal oxide catalyst. This is a method for producing benzophenoneazines.

The imines of the present invention are those represented by the general formula above, and specific examples include benzophenone imine, 2
-3- or 4-methylbenzophenonimine, 2-3.
- or 4-ethylbenzophenonimine, 2-3- or 4-butylbenzophenonimine% 2-3- or 4-amylbenzophenonimine, 2-3- or 4-decylbenzophenonimine, 2-, 3- or 4-methoxy Benzophenonimine, 4-cyclohexylbenzophenonimine, 4-phenylbenzophenonimine, 2.4
-dimethylbenzophenonimine, 2-methyl-4-ethylbenzophenonimine, 2-methyl-4-butylbenzophenonimine, 2,2'- or 4,4'-dimethylbenzophenonimine, 2- or 4-chlorobenzophenonimine, 2 -Chlor-4-methylbenzophenonimine, 4-nitrobenzophenonimine, 2,4-dinitrobenzophenonimine, 4-hydroxybenzophenonimine, 4-N-N dimethylcarbamoylbenzophenonimine, 4-cyanobenzophenonimine, fluorenoneimine, 4-acetyl benzophenone imine,
Examples include 4-acetoxybenzophenone imine, 4-methoxycarbonylbenzophenone imine, 4-N-N dimethylbenzophenone imine, and the like.

In the present invention, it is usually preferable to use an imination reaction solution of benzophenones as the imine. In this case, since unreacted benzophenones act as a solvent, it is not necessary to add a solvent, but the azines produced by the reaction do not necessarily need to be added. A solvent can also be added to aid in dissolution and to keep the reaction system in solution.

The solvent is preferably a solvent that is difficult to be oxidized in the oxidation reaction of imines and helps dissolve the product azine, and is particularly poorly miscible with water and has a low viscosity.
For example, benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, nitrobenzene, dinitrobenzene, diphenyl, phenanthrene, anisole, diphenyl ether, acetophenone, benzyl, fluorenone, benzonitrile, hexane, heptane, cyclohexane, cyclooctane, ethylene dichloride, tetra Chlorethylene, diisopropyl ether,
Examples include dipropyl ether, diisobutyl ketone, butyl acetate, phenyl benzoate, and dimethyl phthalate.

The metal oxide catalyst used in the present invention includes transition elements of the periodic table (Ib, nb, mb, ■b, vb,
elements belonging to the 4.5.6 period of the group VIB, ■b1■) and the typical element groups (IIIa, IVa.

It is a metal oxide of an element belonging to period 5.6 of Va, VIa).

Of course, these metal oxides may be used alone or in combination.

Among these, Cr, Mn, Fe, Co, and Ni, which belong to the group ■b, ■b, and ■group and belong to the fourth period.

TI belonging to Ha or VIa group and belonging to the 6th period.

Metal oxides of Cu and Ag of the Pb1 and Ib groups are preferred.

Specific examples include nickel monoxide, dinickel tetroxide, dinickel trioxide, cobalt monoxide, dicobalt tetroxide, dicobalt trioxide, -iron oxide, triiron tetroxide, diiron trioxide, Nichrome oxide, chromium dioxide, nichrome pentoxide, manganese monoxide, manganese trioxide, dimanganese tetroxide, manganese dioxide, -copper oxide, -dicopur oxide, -silver oxide, -two-chain oxide, silver, dithallium trioxide , -dithallium oxide, -lead oxide, dilead tetroxide, and lead dioxide.

The catalyst of the present invention can be prepared by various methods of increasing activity and selectivity that are used with conventional solid catalysts.

It can be used by being supported on a carrier for the purpose of improving activity and selectivity by increasing surface area.

The carrier may be any carrier as long as it is stable under the reaction conditions and does not inhibit the reaction, such as activated carbon, asbestos, diatomite, magnesia, silica gel, silicon carbide, celite, alumina, which are commonly used as carriers.
Silica alumina, alumina magnesia, titanium oxide (rutile), pumice, bauxite, alundum, corundum, brick, boria, thoria, barium sulfate, spinel,
In addition to clay, asbestos, talc, etc., resins and cements with excellent heat resistance and oxidation resistance can also be used.

In the case of a single-component metal oxide, the metal of the metal,
hydroxides, carbonates, nitrates, halides, nitrites,
Organic acid salts such as formates, acetates, oxalates, etc. are calcined or combined with oxidizing agents such as hydrogen peroxide, peracetic acid, oxygen, air, ozone, sodium hypochlorite, potassium hypochlorite, Obtained by reaction with sodium peroxide, barium peroxide, performic acid, permaleic acid, benzoyl peroxide, MEK peroxide, pertoluic acid, chlorine, nitric acid, aqua regia, etc. oxide,
Salts can be reduced by, for example, hydrogen reduction, reduction with carbon monoxide, formalin, formic acid, hydrazine, sodium boron hydride, etc., electrolytic reduction, reduction using differences in ionization tendency, etc.

In the case of multi-component metal oxides, they are obtained by calcining multi-component metals, hydroxides, carbonates, etc. obtained by coprecipitation, kneading, etc., or by reaction with an oxidizing agent. In some cases, these multi-component metal oxides, salts, etc. can be removed by reduction treatment.

General methods such as ion exchange, impregnation, coprecipitation, and kneading are used to support single-component and multi-component catalysts on common carriers. can be used as carrier-supported metal oxides or metal catalysts in the aforementioned methods.

The catalyst of the present invention usually has a tendency to exhibit high activity when the metal compound is in a highly oxidized state, but it can of course be used as it has activity even in a low oxidized state.

Furthermore, it does not need to be a pure metal or its oxide, but a metal oxide that is produced in a reaction system, or a hydroxide, halide, sulfide, phosphide, carbonate, nitrate, or silicate of these metals. , borates, sulfates, phosphates, formates, oxalates, acetates, and the like.

For the purpose of improving the activity and selectivity of the catalyst used in the present invention, the following substances may be added singly or in combination as a promoter.

For example, alkali metals (Li, Na, Rb, Cs)
, alkaline earth metals (Be, Mg, Ca, Sr,
Ba), oxides, hydroxides, halides, sulfides, phosphides, carbonates, nitrates, silicates, borates, sulfates, phosphates, formates, acetates, oxalates, etc. compounds, ammonium salts such as ammonium carbonate, ammonium chloride, ammonium phosphate, ammonium formate, and ammonium acetate, as well as simple substances of boron, phosphorus, sulfur, and silicon, or their oxides, hydrides, and halides,
Compounds such as sulfides, and AI, Ga, Ge, A
s%Se alone, or their oxides, hydroxides, halides, sulfides, phosphides, carbonates, nitrates,
Examples include sulfate, formate, acetate, oxalate, etc.

The catalyst in the present invention may be in various forms, such as particles, powder, etc., either as a single catalyst or supported on a carrier.
It can be used in fibrous, spongy, and other forms.

The shape of the catalyst is preferably selected depending on the type of reaction.

For example, if the catalyst is prepared in granular form, the particle shape, specific gravity,
Although it depends on the size, etc., a fixed bed is usually preferable, and if it is in powder form, it is preferable to use a method in which it is dispersed in the reaction liquid phase under stirring or a fluidized bed method.

There is no particular restriction on the amount of catalyst used, but it is usually
．． 01 to 50 wt%, preferably 0.1 to 30 wt%,
Particularly preferably, it is used in a range of 0.5 to 20 wt%.

The reaction conditions for the oxidation reaction of the present invention cannot be uniformly defined depending on the activity of the catalyst, the reaction type, etc., but the reaction temperature is 60 to 300°C, preferably 70 to 250°C, more preferably ioo to 230°C. be.

The reaction time is influenced by the activity of the catalyst, the desired conversion rate, etc., but is usually in the range of 0.1 to several tens of hours.

As molecular oxygen, oxygen gas alone may be supplied to the reaction system, or a mixed gas containing an inert gas such as nitrogen and oxygen gas, such as air, may be used.

The pressure is not particularly limited, whether it is normal pressure or pressurization, but in the case of oxygen gas alone, 1 to 20 atm, and in the case of air, about 1 to 40 atm is appropriate.

The method of supplying oxygen gas or a mixed gas containing oxygen gas to the reaction system may be either a flow type or a closed type, but a blow flow type is preferable in order to suppress hydrolysis of imines by reaction product water. Further, it is preferable to use dried oxygen gas or a mixed gas containing oxygen gas.

The scope of the present invention also includes a method of producing azines in one step by simultaneously adding ammonia and an oxygen-containing gas to benzophenones and reacting them.

According to the method of the present invention, since the catalyst used is a heterogeneous catalyst, it can be recovered and reused with a simple operation, making it an industrially extremely advantageous method for producing azines. be.

Example 1 3 of benzophenone imine (purity 26.6%, remainder benzophenone) (imine 44.1 mmol) was charged into a reactor and heated to 200° C. while nitrogen was flowing through an inlet inserted into the bottom of the reactor. Then, 0.61 (3.63 mmol) of commercially available powdered dinickel trioxide, which is a catalyst, was added.

The mixture was then stirred for 3 hours while blowing oxygen at a rate of 100 ml/min under normal pressure.

After 3 hours, the reaction solution was analyzed by gas chromatography, and the yield of benzophenone azine was 54% (11,9
(1 mol) was produced with a selectivity of 99% or more.

The production of benzophenone azine was confirmed as follows.

After removing the catalyst from the reaction solution using a glass filter while keeping the temperature at 100° C., ethanol was added to the tear fluid, and the precipitated crystals were separated by E using a glass filter.

After washing the crystals with ethanol, they were immediately dried under reduced pressure, and the bright pale yellow powder obtained was analyzed, and the melting point was 1.
63-164°C (literature 162°C), mass spectrum,
The infrared spectrum and nuclear magnetic resonance spectrum were both completely consistent with those of the benzophenone azine standard material.

Example 2 Commercially available powdered dithallium trioxide 0.61 (1,
The same procedure as in Example 1 was carried out except that 3 mlJ mol) was used.

The reaction was carried out for 3 hours, and benzophenone azine was produced in a yield of 89% (19.6 mmol), and the selectivity was 99% or more.

Example 3 The same operation as in Example 1 was carried out except that 1.2 f (7.26 mmol) of catalyst powder dinickel trioxide was used.

The reaction was carried out for 3 hours, and benzophenone azine was obtained with a yield of 84% (18.5 mmol).

Example 4 The same operation as in Example 2 was performed except that the reaction temperature was 160°C.

The reaction was carried out for 3 hours, and benzophenone azine was obtained with a yield of 30% (6.6 mmol).

Example 5 The procedure was exactly the same as in Example 3, except that air was used instead of oxygen.

The reaction was carried out for 3 hours and benzophenone azine was obtained with a yield of 38% (8.4 mmol).

Example 6 The same procedure as in Example 1 was carried out, except that 0.61 (1,41 mmol) of powdered dithallium oxide (7 mol) was used as the catalyst.

The reaction was carried out for 3 hours, and benzophenone azine was obtained with a yield of 44% (9.7 mmol).

Examples 7 to 11 The catalytic effects of various metal oxides were investigated in exactly the same manner as in Example 3.

The results are summarized in Table 1.

Examples 12-16 Benzophenone imine (purity 52%, remainder benzophenone) in a 300 rIL stainless steel autoclave
10? (28,7 mmol) and O-dichlorobenzene
50 TLl and various metal acids** shown in Table (2) were charged, and then oxygen was exposed at room temperature to 12 kg/cni (gauge pressure), and then heated to 20°C.

At this point, stirring was started and the reaction was carried out for 2.5 hours.

The results are summarized in Table 2. Example 17 Commercially available powdered nickel hydroxide was heated in air using an electric furnace.
It was baked at 40°C for 5 hours.

The Ni content of the obtained catalyst was 67.7% (theoretical Ni content of dinickel trioxide was 70.9%).

Exactly the same operation as in Example 3 was performed except that dinickel trioxide prepared by the above method was used.

The reaction was carried out for 3 hours and benzophenone azine was obtained with a yield of 79% (17.4 mmol).

Example 18 α-alumina was immersed in a 40% aqueous nickel nitrate solution to impregnate it with nickel nitrate, and then poured into a 10% aqueous sodium carbonate solution to precipitate the nickel into the α-alumina as nickel carbonate and nickel hydroxide. Ta.

The alumina was passed through a glass filter once, thoroughly washed with water, dried in a dryer at 120°C for 5 hours, and then fired in air at 260°C for 3 hours using an electric furnace.

The same operation as in Example 1 was performed except for using the α-alumina-supported dinickel trioxide catalyst (supported amount: 3.3% as nickel) 31 prepared by the above method.

The reaction was carried out for 3 hours, and benzophenone azine was obtained with a yield of 33% (7.3 mmol).

Example 19 Commercially available nitric acid 8. OP and 5.0 g of zinc nitrate were dissolved in 1 oocc of distilled water, and a 10% ammonium carbonate aqueous solution was added dropwise to the solution while stirring to form a precipitate of nickel carbonate and zinc carbonate.

The amount of ammonium carbonate aqueous solution dropped was about 2 oocc, and the time required for dropping was 1 hour.

After dropping, the mixture was left to stand for a day and night, and then the precipitate was filtered off and washed with water.

Next, this was dried at 100° C. for 2 hours, and then fired at 270° C. for 2 hours under air circulation.

The catalyst thus obtained was crushed in a mortar and used as a powder for the reaction.

The nickel content in the catalyst is 43 wt%.

The same procedure as in Example 1 was carried out except that 0.75P of the catalyst prepared by the above method was used and the reaction time was 2 hours. Obtained.

Example 20 Example 1 except that 0.6 f (4.2 mmol) of commercially available powder dicopper oxide was used as the catalyst and the reaction time was 2 hours.
By operating in exactly the same manner as above, benzophenone azine was obtained with a yield of 84.1% (18.5 mmol).

Claims (1)

[Scope of Claims] 1 General formula (R1 and R2 in the formula may be the same or different and are a chain, cycloaliphatic or aromatic hydrocarbon group having 1 to 10 carbon atoms or an ether group thereof) , an acyl group, an acyloxy group, an alkoxycarbonyl group, a halogen, a hydroxy, a nitro, an amido, a cyano, a group selected from the group consisting of a disubstituted amino group, or R1 and R2 taken together form a single bond or group. m%n is 0 or an integer from 1 to 5.) The general formula ( A method for producing a benzophenone azine represented by the formula (wherein R1, R2, m, and n are the same as in general formula (I)).