JPH035380B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing an acid fluoride. More specifically, the production of an acid fluoride, which is characterized by reacting an organic halide with an alkali metal fluoride or ammonium fluoride and carbon monoxide in the presence of a carbonylation catalyst at a reaction temperature of 250°C or lower. It is about the method. [Prior Art] Acid fluorides are useful acylating agents because they exhibit strong acylating power and are chemically stable and less susceptible to hydrolysis than acid chlorides and acid bromides. Conventionally, various methods for producing acid fluorides have been known, but it is customary to use special, dangerous, or expensive fluorinating reagents such as hydrogen fluoride for carboxylic acids or acid chlorides, and it is difficult to produce them industrially. This is not considered an advantageous manufacturing method. On the other hand, as a method for producing acid fluorides using a carbonylation reaction, an aromatic halide is reacted with sodium fluoride and carbon monoxide using palladium chloride, palladium bromide, paldium carbon, or rhodium carbon as a catalyst. is known (USP 3632643). Furthermore, a method in which a similar reaction is carried out using nickel carbonyl or a nickel salt as a catalyst is also known (USP 2696503). [Problems to be solved by the invention and objects of the invention] However, in these carbonylation reactions, the reaction temperature is at least 250°C, preferably 300°C to
Because it requires a temperature of 400°C and is carried out under extremely harsh conditions with a carbon monoxide pressure of 600 to 900 atmospheres, and the reaction yield is low, it can hardly be considered an economically superior production method. Also, related to the harsh reaction conditions, organic halides and heterocycles in which a halogen atom is directly bonded to an olefinic unsaturated bond are chemically unstable and tend to polymerize or decompose under such conditions. It is thought that organic halides having the following are not suitable as reaction substrates for the carbonylation, and in fact, no examples of such reactions have been known to date. The present invention aims to provide a novel method for producing a wide range of acid fluorides by carbonylation. ^[ Means for Solving the Problems] The present invention is based on the general formula R ¹ X represents halogen) together with an alkali metal fluoride or ammonium fluoride,
General formula consisting of reaction with carbon monoxide in the presence of a carbonylation catalyst containing at least one metal selected from palladium, platinum, rhodium and cobalt at a temperature of 250°C or less
This is a method for producing an acid fluoride represented by R ¹ COF (R ¹ has the same meaning as above). The organic group R ¹ of the organic halide (general formula ^{R 1} It may be substituted with an inert substituent other than a substituent having an active hydrogen such as a group, such as an alkoxy group, an alkoxycarbonyl group, an acyl group, an acyloxy group, a nitrile group, etc. Examples of these organic groups ^R1 include phenyl group, p-tolyl group, p-methoxyphenyl group, m-phenoxyphenyl group, p-biphenylyl group, p-acetylphenyl group, α- or β - Naphthyl group, 2- or 3-thienyl group, 2- or 3-furyl group, 2- or 5-thiazolyl group, vinyl group, 1- or 2-propenyl group, α- or β-styryl group, benzyl group, etc. can be mentioned. X is a halogen atom,
Considering the reactivity to the catalyst, it is preferable to use iodine or bromine atoms. The method of the present invention is carried out in the presence of an alkali metal fluoride or ammonium fluoride, and the alkali metals include lithium, sodium,
Potassium, rubidium, and cesium are preferably used, and the use of fluorides of rubidium and cesium is particularly advantageous in terms of reaction rate. The amount of these alkali metal fluoride or ammonium fluoride used may be less than the equivalent amount relative to the organic halide (general formula R ¹ . The catalyst used in the present invention is a metal complex consisting of at least one metal selected from palladium, platinum, rhodium, and cobalt, and a two-electron donating ligand of 1 equivalent or more with respect to the metal. This metal complex can be formed in advance outside the reaction system and supplied into the reaction system, or can be formed within the reaction system. When forming within a reaction system, the metal compound and a compound serving as a two-electron donating ligand are supplied into the reaction system and reacted under carbonylation reaction conditions. In this case, any metal compound may be used as long as it is capable of forming a complex with a compound that becomes a two-electron donating ligand. Examples of such metal compounds include organic acid salts, inorganic acid salts, and organic complexes. , carbonyl compounds, and the like. Specific examples include cobalt carbonyl, cobalt carbonate, rhodium carbonyl, chlorodicarbonyl rhodium dimer, chloro(1,5.hexadiene) rhodium dimer, rhodium chloride, palladium chloride, palladium acetate, chloro(π-allyl) Examples include palladium dimer. Compounds that serve as two-electron donor ligands suitable for the reaction of the present invention include organic nitrogen, organic phosphorus, and organic arsenic compounds, including tertiary amines, nitriles, tertiary amides, phosphines, and phosphites. , arsine, and particularly suitable ligands include benzonitrile, pyridine, dipyridyl, triphenylphosphine, 1,4-bis(diphenylphosphino)butane, and tri(o-tolyl). Examples include phosphine, triphenylphosphite, tributylphosphine, triphenylarsine, and the like. Therefore, suitable complex catalysts for the reaction of the present invention include hexacarbonylbis(triphenylphosphine)cobalt, chlorotris(triphenylphosphine)rhodium, chlorocarbonylbis(triphenylphosphine)rhodium, and dichlorobis(triphenylphosphine)rhodium. in) palladium, dichlorobis(benzonitrile)palladium, dichlorobis(triphenylarsine)palladium, tetrakis(triphenylphosphine)palladium, carbonyltris(triphenylphosphine)palladium, maleic anhydride bis(triphenylphosphine)palladium, Dichloro-1,1'-bis(diphenylphosphinoferrocene)palladium, dichloro-α,ω-bis(diphenylphosphino)
Alkane palladium (alkanes have 1 to 10 carbon atoms)
linear or branched), bisacetatobis(triphenylphosphine)palladium, iodophenylbis(triphenylarsine)palladium, chlorobenzoylbis(triphenylphosphine)palladium, dichlorobis(triphenylphosphine)platinum , dichlorobis(benzonitrile)platinum, and the like. The amount of these catalysts used may be a so-called catalytic amount, and is generally selected in a molar ratio of 0.1 to 0.00001 to the halogen compound. The present invention uses 0°C to 250°C, preferably 50°C to 200°C.
The partial pressure of carbon monoxide is 0.1 atm or more, preferably in the range of normal pressure to 200 atm. The method of the present invention can be carried out with or without a solvent, but when using a solvent, commonly used solvents, except those containing active proton sources such as amino groups, hydroxyl groups, and carboxyl groups, i.e. benzene, toluene, hexane, ether, tetrahydrofuran, acetonitrile,
Selected from methylene chloride, acetone, hexamethylphosphorotriamide (HMPA), DMF, N-methylpyrrolidone, dibutyl ether, etc. Separation and purification of the product from the reaction mixture is generally easily accomplished by filtering off solid inorganic salts and then distilling the product. In the method of the present invention, by carbonylating a wide range of organic halides under mild conditions,
Acid fluorides can be obtained industrially advantageously. [Example] Aspects of the present invention will be explained in more detail based on Examples. Example 1 4 mmol of iodobenzene, cesium fluoride
5mmol, PdCl ₂ (PPh ₃ ) ₂ 0.06mmol, benzene 5ml
was placed in an autoclave with an internal volume of 50 ml, carbon monoxide was introduced to a pressure of 150 atm, and the mixture was stirred in an oil bath at 120°C for 16.5 hours. As a result of analysis by GLC, the conversion rate of iodobenzene was 100% and the yield of benzoyl fluoride was 94.6%. When excess diethylamine was added to the entire reaction solution, it was observed that N,N-diethylbenzamide was produced in an amount corresponding to benzoyl fluoride. Examples 2 to 20 and Comparative Example 1 The reaction of Example 1 was repeated at various temperatures and carbon monoxide pressures by changing the type of catalyst, fluoride, or solvent, and the results shown in Table 1 were obtained. Examples 21 to 29 and Comparative Example 2 Various halides in place of iodobenzene
Example 1 was repeated using 4 mmol and changing the solvent and reaction temperature as appropriate, and the results shown in Table 2 were obtained. Example 30 4 mmol of iodobenzene, 5 mmol of CsF, PdCl ₂
0.06 mmol of (PPh ₃ ) ₂ and 5 ml of propionitrile were charged into a flask with an internal volume of 20 ml, connected to a rubber vent, and stirred at 80° C. under normal pressure of carbon monoxide for 9 hours.
As a result of GLC analysis, the conversion rate of iodobenzene was 99
%, and the benzoyl fluoride yield was 98%. Comparative Example 3 Example 30 using PdCl ₂ instead of PdCl ₂ (PPh ₃ ) ₂
repeated. The yield of benzoyl fluoride was only 28%.

【table】

【table】

[Table] Comparative example 4 NaF instead of GsF, PdCl ₂ (PPh ₃ ) ₂
Example 30 was repeated using _PdCl2 . The yield of benzoyl fluoride was only 0.4%. Examples 31-37 Table 3 shows the results of repeating Example 30 using various halides in place of iodobenzene and changing the reaction time to 16.5 hours.

[Table] Example 38 Example 1 was repeated using ammonium fluoride in place of cesium fluoride, and as a result, 14.4% benzoyl fluoride was obtained. Example 39 The reaction of Example 1 was repeated using [Co(CO) ₃ PPh ₃ ] ₂ instead of PdCl ₂ (PPh ₃ ) ₃ . The yield of benzoyl fluoride was 67.0%. Example 40 [Pd(π-C ₃ H ₅ ) instead of PdCl ₂ (PPh ₃ ) ₂
The reaction of Example 1 was repeated using 0.03 mmol of Cl] ₂ and 0.12 mmol of PPh ₂ CH ₃ . The yield of benzoyl fluoride was 76.0%.

Claims (1)

[Claims ^] 1 General formula R ¹ An organic halide represented by is treated in the presence of a complex catalyst consisting of at least one metal selected from palladium, platinum, rhodium, and cobalt and a two-electron donating ligand of 1 equivalent or more to the metal. , a fluorinating agent selected from the group consisting of alkali metal fluorides or ammonium fluoride, and carbon monoxide.
A method for producing an acid fluoride represented by R ¹ COF (R ¹ has the same meaning as above). 2. The method according to claim 1, wherein the halogen atom represented by X is bromine or iodine. 3. The method according to claim 1 or 2, wherein the complex catalyst is formed in advance outside the reaction system. 4. The method according to claim 1 or 2, wherein the complex catalyst is formed within the reaction system.