JPH04159236A - Method for producing biphenyl compounds - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing biphenyl compounds useful for medicines, agricultural chemicals, intermediates for dyes and pigments, polymer raw materials, plasticizers, preservatives, photographic materials, etc. .

[Conventional technology and its problems]

Hitherto, a method for producing a biphenyl compound is known in which an aromatic compound is dehydrogenated and trimerized by supplying molecular oxygen to a reaction system in the presence of a palladium catalyst. However, in this method, large amounts of high-boiling by-products are produced and the selectivity for biphenyl compounds is low. Furthermore, when a mono-substituted aromatic compound or a di-substituted aromatic compound is used, six types and three types of biphenyl compound isomers are generated, making it difficult to isolate and purify the desired biphenyl compound. It is.

In order to solve the above problems, a method has been reported in which a biphenyl compound is produced by reductively coupling an aromatic halide in the presence of a catalyst. The method of producing biphenyl compounds by bringing copper powder into contact with aromatic halides is known as the Ullmann reaction (Chemical Review).

(1964, Vol. 64, p. 613), but this reaction requires a stoichiometric amount of copper powder, and this reaction is not suitable for aromatic compounds having substituents such as hydroxyl groups, carboxyl groups, and amino groups. The drawback is that it cannot be applied.

A method for producing biphenyl compounds by reacting aromatic iodides in the presence of a trialkylamine and a palladium catalyst reported by Jou F, C1ark et al.
rnal chemical 5ociety Per
kinI, 1975, p. 121), the reaction does not proceed when cheap aromatic bromide is used as a starting material, and requires expensive aromatic iodide, which is difficult to obtain, and many reducing compounds are By-product.

A method in which aromatic bromide can be used as a starting material is a method using a cyclooctadiene complex of nickel, as reported by M. Semmelhack et al.
al of American Chemical 5
ociety, 1971, vol. 93, p. 5908)
A method using triphenylphosphine complex of ``t-Kel'' reported by Kende, A. (Tetrahedr
on Letters, 1975, p. 3375), but both require a stoichiometric amount of nickel and cannot be called industrial methods. In addition, an improved method of adding zinc to the above reaction system has been reported (Tetrahedron Letters).
, 1977, p. 4089), but this method requires large amounts of zinc.

[Technical means to solve problems]

The present invention provides a method for producing a biphenyl compound that does not produce isomeric by-products using an aromatic brominated compound that is easy to synthesize and relatively inexpensive as a starting material.

The present invention is characterized by reacting an aromatic bromide represented by the following formula (I) in the presence of a) a palladium catalyst, b) an alkali metal hydroxide, and C) -carbon oxide. Formula (II)
The present invention relates to a method for producing a biphenyl compound shown in the following. In the above formula, R represents an alkyl group, an alkoxy group, a nitro group, a formyl group, an amino group, a carbalkoxy group, a hydroxyl group, a carboxyl group, and a halogen atom, and n is θ
It is an integer between ~2.

Specific examples of the aromatic bromine in the present invention include bromobenzene, o-lm= or p-bromotoluene,
l,2-dimethyl 4-bromobenzene, p-methoxybromobenzene, 4-bromoveratrol, p-nitrobromobenzene, p-bromobenzaldehyde, p-bromoaniline, p-bromobenzoic acid, methyl p-bromobenzoate , dimethyl 4-bromophthalate, o-lm- or p-bromophenol, 4-bromoguaiacol,
Examples include p-chlorobromobenzene.

Examples of the palladium catalyst in the present invention include (1)/<radium alone, (2) palladium metal salts or palladium metal oxides, and (3) complexes having organic ligands of palladium metal or metal salts. I can do it.

Palladium (1) can be used alone, but it can also be supported on a porous carrier such as activated carbon, graphite, silica gel, alumina, silica alumina, or molecular sieve.

Specific examples of palladium metal salts and oxides in (2) include palladium acetate, palladium nitrate, palladium chloride,
Examples include palladium bromide, palladium iodide, sodium palladium chloride, and palladium oxide.

As the organic ligand of (3), acetoxy group (OAc)
, acetonitrile (CH,CN), benzonitrile (
PhCN), acetylacetone (acac), 1,5-
Examples include cyclooctadiene (COD), triphenylphosphine (PPh3), and specific examples of complexes include Pd(OAC)t(CHsCN)t, PdC
1z(PhCN)t, Pd(acac)t, PdC1,
(COD), PdBr*(PPhs)t, Pd(PPh
s) 4 etc. When using these complexes, the complex may be added directly to the reaction system, but it is also possible to separately add the palladium salt and the ligand to the reaction system to generate the complex in the reaction system.

The amount of palladium catalyst used in the present invention is 0.10 to 50% by weight, preferably 0.50 to 10% by weight, based on the aromatic bromide.

Carbon monoxide used in the present invention does not necessarily have to be a highly pure gas. For example, it can be used in combination with an inert gas such as nitrogen gas or carbon dioxide gas.゛Specific examples of the alkali metal hydroxide in the present invention include sodium hydroxide and potassium hydroxide. Although this hydroxide can be added directly to the reaction solution, it is preferably added as an aqueous solution of 10% by weight or more. The amount of hydroxide used can be 0.5 to 50 times the mole of the aromatic bromide, particularly 0.5 to 50 times the mole of the aromatic bromide.
It is preferable to use 8 to 25 times the mole amount.

In the present invention, it is not necessary to use a particular reaction solvent, but examples include diethylene glycol, diethyl ether, 1.4
- ethers such as dioxane, aromatic compounds such as benzene, toluene, xylene, nitrobenzene, chlorobenzene, nitriles such as acetonitrile, benzonitrile, N.

N-dimethylacetamide, dimethyl sulfoxide, N
-Methylpyrrolidone, hexamethylphosphoramide can be used.

The reaction of aromatic bromides in the present invention can be carried out under normal pressure or increased pressure. When the reaction is carried out under pressure, the reaction pressure including the -carbon oxide gas pressure is preferably up to about 150 kg/carG. The reaction temperature is usually lO~250°C
and preferably 70 to 200°C.

According to the present invention, there is provided a method for producing a biphenyl compound that uses a relatively inexpensive aromatic brominated compound as a starting material, produces very little isomer by-products other than the desired biphenyl compound, and is therefore very economically superior. Ru.

〔Example〕

Examples of the present invention are shown below. In addition, in the following examples, substantially no isomeric by-products other than the desired biphenyl compound were detected.

Example 1 17.3 g of P-bromophenol, 510%, was placed in a rotary stirring type stainless steel autoclave with an internal volume of 300 ml.
1.06 g of Pd-C, 25 ml of 50% NaOH aqueous solution,
Charge 40 tnl of xylene and -20 kg/carbon oxide.
Co? G was injected into the flask, and the reaction was carried out at 85°C for 3 hours.

Next, 50 rAl of water was added to the obtained reaction product, acidified with hydrochloric acid, and the solution was extracted three times with 60 ml of diethyl ether. By concentrating the diethyl ether solution, white crystals of 4,4°-dihydroxybiphenyl 5.8
It was possible to separate g.

Example 2 4.
3.4 g of white crystals of 4°-dihydroxybiphenyl were obtained.

Example 3 4.
2.0 g of white crystals of 4-dihydroxybiphenyl were obtained.

Example 4 4.
3.7 g of white crystals of 4°-dimethylbiphenyl were obtained.

Example 5 P-bromonide instead of P-bromophenol
Example 1 except that 20.2 g of lobenzene was used.
In the same manner as above, 5.2 g of white crystals of 4,4°-dinitrobiphenyl were obtained.

Example 6 P-
'Near' Lomo 7z/Jv 17.3g, l0rX
Pd-C1.06g, 50% NaOH aqueous solution 25-,
Charge 40 ml of xylene, add -carbon oxide under normal pressure, 41
/ hour through the reaction solution and heated at 110°C with stirring for 6 hours.
Allowed time to react.

Extracted with diethyl ether in the same manner as in Example 1, and extracted with 4.4°
-4.1 g of white crystals of dihydroxybiphenyl were obtained.

Example 7 Instead of 25 ml of 50% NaOH aqueous solution, 20% Na
White crystals of 4゜4゛-dihydroxybiphenyl 3.7 were prepared in the same manner as in Example 6 except that OH aqueous solution 25-
I got g.

Example 8 Instead of 25 ml of 50% NaOH aqueous solution, 20% KO
White crystals of 4,4°-dihydroxybiphenyl were prepared in the same manner as in Example 6, except that 25 ml of H aqueous solution was used.
I got g.

Example 9 White crystals of 4,4'-dihydroxybiphenyl were prepared in the same manner as in Example 6, except that N,N-dimethylacetamide 40- was used instead of xylene 40-, and the reaction was carried out at 110°C for 3 hours. Patent applicant who obtained 5.1g Ube Industries, Ltd.

Claims (1)

[Claims] An aromatic bromide represented by the following formula (I),
There are chemical formulas, tables, etc. ▼ (I) A biphenyl represented by the following formula (II), which is reacted in the presence of a) a palladium catalyst, b) an alkali metal hydroxide, and c) carbon monoxide. Method of manufacturing the compound. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (In the above formula, R is an alkyl group, an alkoxy group, a nitro group,
Represents a formyl group, amino group, carbalkoxy group, hydroxyl group, carboxyl group, and halogen atom, n
is an integer from 0 to 2. )