Method for producing aromatic diether and corresponding method for producing polyaryletherketone

Abstract

The present invention relates to a process for producing aromatic diethers, which comprises reacting a compound A comprising at least two halogenated aromatic groups with a compound B, optionally in the presence of a compound C serving as a reaction solvent, wherein B is an aromatic alkoxide, the molar ratio of compound B to compound A being at least 2:1 and the molar amount of compound C to compound A not exceeding 10:1 where appropriate. The present invention also relates to a process for producing polyaryletherketones.

Description

Technical Field

[0001] The present invention relates to a process for producing aromatic diethers.

[0002] The invention also relates to a process for making polyaryletherketones from at least some of these aromatic diethers. Background Art

[0003] Various industrial processes are known from the prior art for producing polyaryletherketones, for example polyetheretherketone, polyetherketoneketone or copolymers of polyetheretherketone and polyetherdiphenyletherketone.

[0004] The first known route for making polyaryletherketone polymers is based on nucleophilic substitution and is described, for example, in WO 86 / 07599. This process involves polycondensing a difluoromonomer with a monomer containing two phenol functions in a solvent such as diphenylsulfone at elevated temperature (between 280°C and 320°C).

[0005] The second known route is based on an electrophilic substitution reaction between aromatic acid chlorides and aromatic ethers in the presence of a Lewis acid and has been described, for example, in US 4 816 556. In particular, the process for making polyetherketoneketones can be based on diphenyl ether or, alternatively, on 1,4-bis(4-phenoxybenzoyl)benzene as the starting monomer for the polymerization reaction. In US 4816 556, 1,4-bis(4-phenoxybenzoylbenzene) is synthesized by electrophilic substitution between terephthaloyl chloride and an excess of diphenyl ether in o-dichlorobenzene (solvent) in the presence of aluminum chloride (Lewis acid).

[0006] Ke, Y. et al. (1998), Investigations of the practical routes, structure, and properties for poly (aryl ether ketone ketone) polymers (practical routes, structures and properties of poly (aryl ether ketone ketone) polymers). J. Appl. Polym. Sci., 67: 659-677. doi: 10.1002 / (SICI) 1097-4628 (19980124) 67: 4 <659:: AID-APP9> 3.0. CO; 2-P also discloses an experimental method for preparing 1,4-bis (4-phenoxybenzoyl) benzene via a nucleophilic route. In the publication, the method is carried out as follows: 0.10 mol of the compound of formula (I), 0.20 mol of phenol and 0.3 mol of anhydrous potassium carbonate are mixed in 270 mL of dimethylacetamide and 60 mL of toluene under stirring and under a nitrogen atmosphere:

[0007] [Chemical formula 1]

[0008]

[0009] The mixture is gradually heated for 1 hour until a temperature of 158°C is reached. Residual water is removed from the reaction mixture. The reaction mixture is maintained at a temperature of 158°C for 1 hour and then at a temperature of 162°C for 2 hours. The reaction medium is then poured into pure water, and the precipitate is filtered off and air-dried at 108°C for 24 hours. Two recrystallizations from toluene are performed, and a product with a melting point of 224°C is obtained with a yield of 90%, but the purity is not specified. However, the literature indicates that the melting point of 1,4-bis(4-phenoxybenzoyl)benzene should be 215°C. This method also has several disadvantages: it uses large amounts of solvents, especially dimethylacetamide, which poses a risk to human health because it is harmful (by contact / inhalation) and CMR (can harm the fetus). In addition, dimethylacetamide has a high boiling point (165°C), which complicates the step of drying the resulting product. Finally, the water produced during the reaction is soluble in dimethylacetamide, but it is difficult to separate from it, which complicates the recycling of the solvent for reuse in subsequent processes.

[0010] Purpose

[0011] It was an object of the present invention to specify an improved process for the preparation of aromatic diethers which can be carried out in particular on the industrial scale.

[0012] According to certain embodiments, the object of the present invention is to propose a process for producing high-purity aromatic diethers in high yield.

[0013] It is also an object of the present invention to specify an improved process for producing polyaryletherketones from the aromatic diethers mentioned. Summary of the invention

[0014] The present invention relates to a method for producing an aromatic diether, comprising: reacting a compound A comprising at least two halogenated aromatic groups with a compound B, optionally in the presence of a compound C serving as a reaction solvent, B being an aromatic alkoxide. The molar ratio of compound B to compound A is at least 2:1 and the molar amount of compound C to compound A does not exceed 10:1 when appropriate (where applicable).

[0015] The process makes it possible to obtain aromatic diethers in highly concentrated reaction mixtures, even in bulk, which makes it possible to optimize the volumetric productivity (amount of material produced per unit volume of equipment). Furthermore, the inventors have noticed, quite surprisingly, that this process allows aromatic diethers to be obtained in yields that are at least equal to and in many cases superior to those of the processes according to the prior art and in good purity.

[0016] In certain embodiments, Compound A is a compound having the following chemical formula:

[0017] [Chemical formula 2]

[0018] X1Ar-[Z i Ar i ] n X2 (II),

[0019] in,

[0020] i is an integer ranging from 1 to 3, and n is an integer equal to 0 or 1;

[0021] X1 and X2 independently represent a halogen atom;

[0022] For any i of Ar i and Ar independently represents a substituted or unsubstituted divalent aromatic group; and

[0023] For any i, Z i independently represents an oxygen atom, a sulfur atom, an alkylene group such as -CH2- or isopropylidene (-C(CH3)2-), a carbonyl group or a sulfonyl group.

[0024] Preferably, X1 and X2 represent the same halogen atom. Even more preferably, they both represent chlorine or fluorine.

[0025] Preferably, for any i of Ar i and Ar independently represents a divalent aromatic group selected from the list consisting of 1,3-phenylene, 1,4-phenylene, divalent 1,1'-biphenylene in 4,4' position, divalent 1,1'-biphenylene in 3,4' position, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene, and even more preferentially independently represents 1,3-phenylene and 1,4-phenylene.

[0026] First, for any i, Z i independently represents an oxygen atom or a carbonyl group and even more preferably represents a carbonyl group.

[0027] According to certain embodiments, in the formula (II) of compound A:

[0028] -i is equal to 2 and n is equal to 1;

[0029] - X1 and X2 both represent a chlorine atom or a fluorine atom;

[0030] -Ar and Ar2 both represent 1,4-phenylene groups;

[0031] -Ar1 represents a 1,3-phenylene or 1,4-phenylene group; and

[0032] -Z1 and Z2 both represent a carbonyl group.

[0033] In certain embodiments, Compound B has the formula:

[0034] Ar'-O-(III), wherein:

[0035] Ar' represents a substituted or unsubstituted monovalent aromatic group, preferably a monovalent aromatic group selected from the list consisting of phenyl, biphenyl and naphthyl. Compound B may in particular be a phenolate.

[0036] In certain embodiments, the molar ratio of compound B to compound A is less than or equal to 3:1, preferably less than or equal to 2.5:1, more preferably less than or equal to 2.3:1, and extremely preferably about 2:1.

[0037] According to certain embodiments, compound B is obtained by deprotonating an aromatic alcohol B" (the conjugate acid of an aromatic alcohol salt B) in situ or ex situ with a base that reacts with B" to obtain compound B, wherein the base is preferentially selected from the list consisting of aromatic or aliphatic alcohol salts, carbonates, metal hydrides (salts) and alkali metals (salts).

[0038] The base reacted with B" may in particular be a linear or branched alkoxide containing 3 to 10 carbon atoms. Preferably, the base is chosen from the list consisting of the following salts:

[0039] isopropoxide, 1,2-dimethylpropoxide, 1,1-dimethylpropoxide, 2,2-dimethylpropoxide, 1,1,2-trimethylpropoxide, 1,2,2-trimethylpropoxide, 1-ethyl-2-methylpropoxide, 1-ethylpropoxide, n-butoxide, isobutoxide, sec-butoxide, tert-butoxide, 2-methylbutoxide, 3-methylbutoxide, 1,2-dimethylbutoxide, 1,3-dimethylbutoxide, 2,3-dimethylbutoxide, 1,1-dimethyl butoxide, 2,2-dimethylbutoxide, 3,3-dimethylbutoxide, 1-ethylbutoxide, 2-ethylbutoxide, 1-propylbutoxide, 1,1,3,3-tetramethylbutoxide, n-pentoxide, 2-pentoxide, 2-methylpentoxide, n-hexoxide, 2-hexoxide, 3-methylpentoxide, 4-methylpentoxide, 2-ethylpentoxide, 2-ethylhexoxide, 2-propylhepoxide, n-hepoxide, 2-hepoxide, 3-hepoxide, n-octoxide and mixtures thereof;

[0040] Even more preferentially, the base may be chosen from the list of salts consisting of isopropoxide, n-butoxide, tert-butoxide, n-hepoxide, n-ocoxide and mixtures thereof.

[0041] The base to be reacted with B" may also be a carbonate.

[0042] The base reacted with B" may in particular be an alkali metal salt. Preferably, the base is a sodium or potassium salt or a mixture of sodium and potassium salts.

[0043] The base reacted with B" may also be sodium metal or potassium metal, preferably sodium metal.

[0044] According to certain embodiments, the molar ratio of the base reacted with B″ relative to B″ is less than or equal to 1:1.

[0045] According to certain embodiments, compound C has a polarity measured at 20°C greater than or equal to 3 Debye, preferentially greater than or equal to 3.5 Debye.

[0046] According to certain embodiments, compound C is selected from the list consisting of: C1-C6-alkyl-2-pyrrolidone, in particular N-methyl-2-pyrrolidone or N-butyl-2-pyrrolidone,

[0047] Sulfoxides, in particular dimethyl sulfoxide or diethyl sulfoxide,

[0048] Sulfones, in particular dimethyl sulfone, diethyl sulfone, diisopropyl sulfone, diphenyl sulfone or tetramethylene sulfone;

[0049] Nitriles, in particular acetonitrile, propionitrile or benzonitrile;

[0050] N-dimethylamides, in particular dimethylacetamide or dimethylformamide;

[0051] and mixtures thereof.

[0052] According to a particular embodiment, compound C may be diphenyl sulfone.

[0053] According to certain embodiments, the molar ratio of compound C to compound A is less than or equal to 7.5:1, preferably less than or equal to 5:1, and more preferably less than or equal to 3:1.

[0054] According to certain embodiments, compound A is reacted with compound B in the absence of any solvent.

[0055] According to certain embodiments, compound A is reacted with compound B in a molten form.

[0056] The process according to the invention also relates to a process for producing a polyaryletherketone polymer, comprising producing an aromatic diether as described above, and reacting the aromatic diether with a compound D comprising at least two acid chloride groups.

[0057] According to certain embodiments, compound D is a compound having the following chemical formula:

[0058] [Chemical formula 3]

[0059] ClC(O)-Ar-[Z j -Ar j ] m -C(O)Cl (IV),

[0060] Wherein, j is an integer ranging from 1 to 3, and m is an integer equal to 0 or 1;

[0061] For any j, Ar j and Ar independently represents a substituted or unsubstituted divalent aromatic group, and preferably represents a divalent aromatic group selected from the list consisting of 1,3-phenylene, 1,4-phenylene, divalent 1,1'-biphenylene at 4,4' positions, divalent 1,1'-biphenylene at 3,4' positions, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene; and

[0062] For any j, Z j independently represent an oxygen atom, a sulfur atom, an alkylene group such as -CH2- or isopropylidene (-C(CH3)2-), or a sulfone; preferably, Z j Represents an oxygen atom.

[0063] According to certain embodiments, the aromatic diether is selected from the list consisting of:

[0064] [Chemical formula 4]

[0065]

[0066] [Chemical formula 5]

[0067] or a mixture thereof; and

[0068] Compound D is selected from the list of compounds consisting of:

[0069] [Chemical formula 6]

[0070]

[0071] [Chemical formula 7]

[0072] or a mixture thereof. DETAILED DESCRIPTION

[0073] Compound A contains at least two halogenated aromatic groups.

[0074] An aromatic group is a group comprising a conjugated ring, the stability of which (due to delocalization) is significantly higher than the stability of a hypothetical localized structure. Advantageously, the aromatic group of compound A is an aromatic hydrocarbon group.

[0075] Each halogenated aromatic group carries at least one halogen atom replacing a hydrogen atom. Advantageously, each halogenated aromatic group carries a single halogen atom replacing a hydrogen atom.

[0076] The aromatic group may also independently contain other substituents for one or more of the remaining hydrogen atoms, this / these other substituents being selected from: alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali metal or alkaline earth metal sulfonate, alkyl sulfonate (salt), alkali metal or alkaline earth metal phosphonate, amine and quaternary ammonium.

[0077] According to certain embodiments, the aromatic group may also independently contain a single other substituent to the hydrogen atom, which substituent is preferably: an aryl group or an alkali metal sulfonate.

[0078] According to certain embodiments, compound A may carry only two halogenated aromatic groups.

[0079] According to certain embodiments, compound A may be a compound having the following chemical formula:

[0080] [Chemical formula 8]

[0081] X1-Ar-[Z i Ar i ] n X2 (II).

[0082] In this formula:

[0083] - i is an integer ranging from 1 to 3, and n is an integer equal to 0 or 1;

[0084] -X1 and X2 independently represent a halogen atom;

[0085] -For any i of Ar i and Ar independently represents a substituted or unsubstituted divalent aromatic group; and

[0086] -For any i, Z i independently represents an oxygen atom, a sulfur atom, an alkylene group such as -CH2- or isopropylidene (-C(CH3)2-), a carbonyl group or a sulfonyl group.

[0087] Preferably, in the compound of formula (II):

[0088] - X1 and X2 may represent the same halogen atom; X1 and X2 may in particular both represent chlorine or fluorine;

[0089] -For any i of Ar iand Ar may independently represent a divalent aromatic group selected from the list consisting of 1,3-phenylene, 1,4-phenylene, divalent 1,1'-biphenylene at the 4,4' position, divalent 1,1'-biphenylene at the 3,4' position, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene; for any i of Ar i and Ar may in particular independently represent 1,3-phenylene and 1,4-phenylene;

[0090] -For any i, Z i can independently represent an oxygen atom or a carbonyl group; for any i, Z i may especially denote a carbonyl group.

[0091] According to a particular embodiment, compound A may be compound A1, A2, A3 or A4 as defined in the examples, or a mixture of these compounds.

[0092] Compound B is an aromatic alkoxide. Compound B comprises an aromatic group (which is advantageously a hydrocarbon group).

[0093] The aromatic ring comprises at least one alkoxide function replacing a hydrogen atom. The aromatic ring may in particular carry a single alkoxide function. Alternatively, the aromatic ring may carry two alkoxide functions.

[0094] The aromatic ring of B may also contain other substituents for one or more remaining hydrogen atoms, this / these other substituents are selected from: alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali metal or alkaline earth metal sulfonate, alkyl sulfonate (salt), alkali metal or alkaline earth metal phosphonate, amine and quaternary ammonium. In particular, the aromatic ring of B may contain a single other substituent for a hydrogen atom, which substituent is preferably: aryl or alkali metal sulfonate.

[0095] According to certain embodiments, compound B is a compound having the following chemical formula:

[0096] Ar'-O - (III).

[0097] In the formula, Ar' represents a substituted or unsubstituted monovalent aromatic group.Preferably, Ar' represents a monovalent aromatic group selected from the list consisting of a phenyl group, a monovalent biphenyl group, and a naphthyl group.

[0098] According to a particular embodiment, compound B is a phenolate.

[0099] The molar ratio of compound B to compound A is at least 2: 1. This is because the reaction of B with A desirably results in a disubstitution reaction of two molecules of B with one molecule of A to form an aromatic diether.

[0100] According to certain embodiments, the molar ratio of compound B to compound A is less than or equal to 3:1, preferably less than or equal to 2.5:1, more preferably less than or equal to 2.3:1, and extremely preferably about 2:1.

[0101] Once the two reagents (ie, Compound A and Compound B) have been placed in contact, the reaction medium is referred to as the "reaction mixture."

[0102] The "reaction time" corresponds to the time it takes for the reagents to react with each other.

[0103] Once the reaction is complete to the desired conversion, preferentially to the complete conversion of compound A to product, the reaction mixture is then referred to as the "product mixture".

[0104] The "reaction temperature" corresponds to the temperature of the reaction mixture during the reaction time.

[0105] “Reaction pressure” corresponds to the pressure which is exerted on the reaction mixture during the reaction time.

[0106] The reaction can be carried out in a reactor. The reactor can be, for example, a glass reactor, a reactor with a glass inner wall, or a reactor made of a stainless steel metal material, or lined with PTFE.

[0107] Preferably, the reaction may be carried out in a reaction mixture which does not substantially contain any water.

[0108] Preferably, the reaction may be carried out in an atmosphere which does not substantially contain any water or molecular oxygen, for example under a nitrogen or argon atmosphere.

[0109] Preferably, the reaction mixture may be stirred for the whole or part of the reaction time. Thus, the reactor is preferably provided with stirring means such as a mechanical stirrer (which may comprise, for example, one or more blades) or a recirculation loop with a pump.

[0110] According to certain embodiments, the reaction can be carried out in the presence of a compound C acting as a solvent. Reagents and / or reaction intermediates and / or reaction products may be at least partially dissolved therein. In these embodiments, the molar amount of compound C relative to compound A does not exceed 10:1, i.e. the reaction is carried out as a concentrated reaction mixture. This has the effect, in particular, of minimizing the introduction of solvent-mediated impurities into the reaction mixture.

[0111] The solvent may be selected from the list consisting of linear or branched alcohols containing 3 to 10 carbon atoms, C1-C6-alkyl-2-pyrrolidones, sulfoxides, sulfones, nitriles, N-dimethylamides and mixtures thereof.

[0112] The solvent may in particular be a linear or branched alcohol comprising 3 to 10 carbon atoms. The alcohol is preferentially non-aromatic. As explained below, the solvent alcohol may in particular be produced during a step of deprotonating an aromatic alcohol (conjugate of an aromatic alkoxide B) with an alkoxide. The solvent alcohol may be selected from the list consisting of isopropanol, 1,2-dimethylpropanol, 1,1-dimethylpropanol, 2,2-dimethylpropanol, 1,1,2-trimethylpropanol, 1,2,2-trimethylpropanol, 1-ethyl-2-methylpropanolate, 1-ethylpropanolate, n-butanol, isobutanol, sec-butanol, tert-butanol, 2-methylbutanol, 3-methylbutanol, 1,2-dimethylbutanol, 1,3-dimethylbutanol, 2,3-dimethyl Butanol, 1,1-dimethylbutanol, 2,2-dimethylbutanol, 3,3-dimethylbutanol, 1-ethylbutanol, 2-ethylbutanol, 1-propylbutanol, 1,1,3,3-tetramethylbutanol, n-pentanol, 2-pentanol, 2-methylpentanol, n-hexanol, 2-hexanol, 3-methylpentanol, 4-methylpentanol, 2-ethylpentanol, 2-ethylhexanol, 2-propylheptanol, n-heptanol, 2-heptanol, 3-heptanol, n-octanol, and mixtures thereof.

[0113] Preferably, the solvent alcohol may be selected from the list consisting of isopropanol, n-butanol, tert-butanol, n-heptanol, n-octanol, and mixtures thereof.

[0114] The solvent may also be a C1-C6-alkyl-2-pyrrolidone, the alkyl group containing 1 to 6 carbons. Advantageously, the C1-C6-alkyl-2-pyrrolidone may be N-methyl-2-pyrrolidone or N-butyl-2-pyrrolidone.

[0115] The solvent may also be a sulfone. Advantageously, the sulfone may be dimethyl sulfone, diethyl sulfone, diisopropyl sulfone, diphenyl sulfone or tetramethylene sulfone. According to a particularly advantageous embodiment, the solvent may be diphenyl sulfone.

[0116] The solvent may also be a nitrile. Advantageously, the nitrile may be acetonitrile, propionitrile or benzonitrile.

[0117] The solvent may also be an N-dimethylamide. Advantageously, the N-dimethylamide is dimethylacetamide or dimethylformamide.

[0118] According to certain embodiments, the solvent has a polarity greater than or equal to 3 Debye, preferably greater than or equal to 3.5 Debye, measured at 20° C. This level of polarity is able to better solubilize reagents and reaction intermediates, thereby promoting nucleophilic substitution reactions.

[0119] The molar ratio of compound C relative to compound A is less than or equal to 10:1. Thus, the process allows the production of aromatic diethers in highly concentrated reaction mixtures, or even in bulk, thereby allowing optimization of volume production. Furthermore, aromatic diethers can be obtained in yields that are at least equal to and in many cases superior to those in prior art processes and in good purity.

[0120] The molar ratio of compound C relative to compound A may be preferably less than or equal to 7.5:1, more preferably less than or equal to 5:1 and extremely preferably less than or equal to 3:1.

[0121] In certain embodiments, Compound C may be an "ACS grade" solvent, i.e., a solvent having a purity limit defined by the American Chemical Society (ACS) purity limit. Compound C may have a purity greater than or equal to 95%, or greater than or equal to 96%, or greater than or equal to 97%, or greater than or equal to 98%, or greater than or equal to 99%. Compound C may specifically not be a high purity solvent of the grade used in analytical chemistry.

[0122] In certain embodiments, certain purity parameters of compound C can still be controlled. Compound C should specifically contain no more than certain amounts, typically less than 100 ppm, preferably less than 50 ppm, of halide ions (Cl - , F - ), alkali metal ions (Na + , K + ), metal ions (Fe(II), Fe(III)) and water.

[0123] According to other embodiments, the reaction can be carried out in the absence of any solvent. The reaction of the reaction mixture is then referred to as a "bulk" reaction. This embodiment has the additional advantage of eliminating any step of recycling the reaction solvent, which would in principle be necessary if the method is to be expanded to an industrial scale. It also has the advantage of limiting the pressure increase inside the reactor.

[0124] According to certain embodiments, the reaction temperature is such that compound A and compound B are in molten form and / or dissolved in the reaction mixture for all or part of the reaction time. Advantageously, compound A is in molten form (above the melting point) and compound B is dissolved in molten compound A and / or, where appropriate, in compound C acting as a solvent, for at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the reaction time.

[0125] According to certain embodiments, the reaction temperature is such that the aromatic diether (the desired reaction product of compound A and compound B) is in molten form and / or dissolved in molten compound A for all or part of the reaction time. In particular, the aromatic diether may be in molten form and / or dissolved in molten compound A for at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95% of the reaction time.

[0126] According to certain specific embodiments, in particular in embodiments in which compound A may be compound A1, A2, A3 or A4 as defined in the examples, the reaction mixture is heated to a temperature of at least 165°C, preferably at least 170°C or at least 180°C or at least 190°C for at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% or at least 95% of the reaction time.

[0127] According to certain embodiments, the reaction time is between 5 minutes and 5 days, preferably between 10 minutes and 24 hours, more preferably between 30 minutes and 5 hours.

[0128] According to certain embodiments, compound A is added to compound B or a mixture of B and C.

[0129] According to certain embodiments, the reaction of compound A and compound B is carried out at atmospheric pressure or near atmospheric pressure.

[0130] Compound B can be obtained by deprotonating an aromatic alcohol B" (the conjugate acid of an aromatic alcohol salt B). B" in turn has the chemical formula: Ar'-OH(IIIa).

[0131] According to a particular embodiment, B" is phenol.

[0132] Compound B" can be deprotonated with a base suitable for deprotonating aromatic alcohols.

[0133] The base may be selected from the list consisting of aromatic or aliphatic alcoholates, carbonates, metal hydrides and alkali metals.

[0134] The base may be selected in particular from linear or branched alkoxides comprising 3 to 10 carbon atoms. In this embodiment, the base becomes an alcohol by reacting with a proton, which, if retained in the reaction mixture, may serve as a solvent. The base may be preferably selected from the list consisting of isopropoxide, 1,2-dimethylpropoxide, 1,1-dimethylpropoxide, 2,2-dimethylpropoxide, 1,1,2-trimethylpropoxide, 1,2,2-trimethylpropoxide, 1-ethyl-2-methylpropoxide, 1-ethylpropoxide, n-butoxide, isobutoxide, sec-butoxide, tert-butoxide, 2-methylbutoxide, 3-methylbutoxide, 1,2-dimethylbutoxide, 1,3-dimethylbutoxide, 2,3-dimethylbutoxide Alkoxides, 1,1-dimethylbutoxide, 2,2-dimethylbutoxide, 3,3-dimethylbutoxide, 1-ethylbutoxide, 2-ethylbutoxide, 1-propylbutoxide, 1,1,3,3-tetramethylbutoxide, n-pentoxide, 2-pentoxide, 2-methylpentoxide, n-hexoxide, 2-hexoxide, 3-methylpentoxide, 4-methylpentoxide, 2-ethylpentoxide, 2-ethylhexoxide, 2-propylhepoxide, n-hepoxide, 2-hepoxide, 3-hepoxide, n-octoxide, and mixtures thereof;

[0135] More preferentially, the base is selected from the list of salts consisting of isopropoxide, n-butoxide, tert-butoxide, n-hepoxide, n-octoxide, and mixtures thereof.

[0136] The base may also be a carbonate. The carbonate may in particular be in the form of a powder having a particle size distribution with a D90 having a value ranging from 45 microns to 250 microns and a D99.5 having a value less than or equal to 710 microns, the particle size distribution being measured by laser diffraction according to standard ISO 13320:2009.

[0137] In certain embodiments in which the base is a salt, the salt may in particular be an alkali metal salt. Preferentially, the salt may be a sodium salt, a potassium salt or a mixture of sodium and potassium salts.

[0138] The base may also be sodium metal, lithium metal or potassium metal, preferably sodium metal.

[0139] The base may also be sodium hydride, lithium hydride or potassium hydride.

[0140] Relative to the reaction of compound A with compound B, the deprotonation step of B" can be performed in situ or ex situ.

[0141] According to certain embodiments, the molar ratio of the base relative to B″ is less than or equal to 1:1. This advantageously ensures a quantitative reaction of the base.

[0142] According to a first variant, the process comprises successively: a first step of deprotonating B" with a base to form compound B, and a second step of reacting compound B with compound A, optionally in the presence of compound C acting as reaction solvent.

[0143] Between the first and second steps, if desired, a step for removing excess B" and / or any solvent used or produced during the first step, and / or water may advantageously be carried out.

[0144] According to a second variant, the base, compound B″, compound A and, if appropriate, compound C can be mixed with one another in any order to form the reaction mixture.

[0145] Once the reaction is complete to the desired conversion, the reaction mixture is referred to as the "product mixture." The product mixture can be purified and the aromatic diether isolated as described below.

[0146] The reaction product residue obtained by the reaction of compound A with compound B can be purified by methods well known to those skilled in the art, including one or more distillation steps, one or more solid / liquid separation steps, one or more washing steps, one or more extraction steps and one or more recrystallization steps.

[0147] In embodiments where the reaction of compound A and compound B is carried out with compound C serving as the reaction solvent, the solvent may be removed to obtain a solvent-free residue of the reaction product.

[0148] When the aromatic diether is sufficiently insoluble in the reaction solvent, it can be recovered via any solid / liquid separation method. The solid / liquid separation can be performed in one or more sequential steps, each of which is selected from the group consisting of centrifugal filtration, sedimentation, centrifugal decantation, vacuum filtration, filter press and gravity filtration. The solid / liquid separation temperature must be sufficiently low to reduce the solubility of the aromatic diether in the reaction solvent.

[0149] Alternatively and advantageously, the reaction solvent can be removed by distillation or also by replacement with another solvent having a lower boiling point.

[0150] Preferably, the solvent-free residue of the reaction product (regardless of whether A and B are reacted in the presence or absence of compound C) can be purified via one or more washing steps or by sublimation or crystallization.

[0151] The purification methods of the reaction product residue containing 1,4-bis(4-phenoxybenzoyl)benzene and / or 1,3-bis(4-phenoxybenzoyl)benzene are explained below. However, those skilled in the art will know how to adapt these methods to other aromatic diethers produced according to the present invention, in particular how to choose the solvent to be used.

[0152] The step of washing the residue comprising 1,4-bis(4-phenoxybenzoyl)benzene and the residue comprising 1,3-bis(4-phenoxybenzoyl)benzene may comprise adding a washing solvent (and selecting a corresponding temperature) in which 1,4-bis(4-phenoxybenzoyl)benzene and / or 1,3-bis(4-phenoxybenzoyl)benzene are slightly soluble but in which impurities such as salts and / or unreacted reagents (particularly phenolates) are soluble. Advantageously, the residue is placed in contact with a protic washing solvent such as water or a water / methanol mixture (95 / 5) at room temperature (25° C.) for a sufficient contact time.

[0153] In certain embodiments, the residue may be ground into fine particles to improve the wash solvent / residue contact surface area, if desired.

[0154] In certain embodiments, the residue is suspended in the wash solvent with stirring such that the residue remains in contact with the wash solvent for a sufficient amount of time.

[0155] The residue / washing solvent mixture is then separated by solid / liquid separation means, for example by filtration or by centrifugation.The solid phase may advantageously be dried to remove any traces of solvent.

[0156] 1,3-bis(4-phenoxybenzoyl)benzene and / or 1,4-bis(4-phenoxybenzoyl)benzene can advantageously be dissolved in an extraction solvent such as chloroform or acetone at room temperature. After solid / liquid separation, a liquid phase mainly containing 1,3-bis(4-phenoxybenzoyl)benzene and / or 1,4-bis(4-phenoxybenzoyl)benzene can be recovered, and a purified product can be finally obtained by removing the extraction solvent (distillation). Advantageously, 1,4-bis(4-phenoxybenzoyl)benzene can be extracted with chloroform. Advantageously, 1,3-bis(4-phenoxybenzoyl)benzene can be extracted with acetone.

[0157] In certain embodiments, the residue may be purified by a final recrystallization step. In these embodiments, the residue is preferentially subjected to only one recrystallization step. This is generally possible due to the relatively low level of impurities to be removed, in part due to the fact that the reaction mixture is produced in a highly concentrated medium, or even in bulk.

[0158] 1,4-Bis(4-phenoxybenzoyl)benzene can also advantageously be recrystallized from toluene.

[0159] 1,3-Bis(4-phenoxybenzoyl)benzene can also advantageously be recrystallized from methanol.

[0160] The purity of the aromatic diether can be determined by a number of commonly used characterization methods, in particular by nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), high performance liquid chromatography (HPLC) and / or ultra performance liquid chromatography (UPLC).

[0161] Preferably, the aromatic diether is obtained in a purity greater than or equal to 95%, preferably greater than or equal to 99% and more preferably greater than or equal to 99.9%, evaluated by NMR (molar percentage).

[0162] Alternatively, the aromatic diether is obtained in a purity greater than or equal to 95%, preferably greater than or equal to 99% and more preferably greater than or equal to 99.9%, evaluated by HPLC (mass percentage).

[0163] The aromatic diether obtained according to an embodiment of the present invention can then be used to carry out an electrophilic polymerization reaction to produce a polyaryletherketone (PAEK) polymer by reacting the aromatic diether with a compound D comprising at least two acid chloride groups.

[0164] Compound D may be a compound having the following chemical formula:

[0165] [Chemical formula 9]

[0166] ClC(O)-Ar-[Z j -Ar j ] m -C(O)Cl (IV),

[0167] Wherein, j is an integer ranging from 1 to 3, and m is an integer equal to 0 or 1;

[0168] For any j, Ar j and Ar independently represents a substituted or unsubstituted divalent aromatic group; and

[0169] For any j, Z j independently represents an oxygen atom, a sulfur atom, an alkylene group such as -CH2- or isopropylidene (-C(CH3)2-), or a sulfone.

[0170] Preferably, for any j, Ar j and Ar represents a divalent aromatic group selected from the list consisting of:

[0171] 1,3-phenylene, 1,4-phenylene, 1,1'-biphenylene having a divalent group at the 4,4' position, 1,1'-biphenylene having a divalent group at the 3,4' position, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene.

[0172] First, for any j, Z j Represents an oxygen atom.

[0173] According to certain embodiments, compound D may be selected from the list consisting of phthaloyl dichloride, isophthaloyl dichloride, terephthaloyl dichloride, or mixtures thereof. Preferentially, compound D may be selected from the list consisting of isophthaloyl dichloride, terephthaloyl dichloride, or mixtures thereof.

[0174] According to certain specific embodiments, the aromatic diether synthesized according to the present invention may be selected from the list consisting of 1,4-bis(4-phenoxybenzoyl)benzene, 1,3-bis(4-phenoxybenzoyl)benzene, or a mixture thereof.

[0175] Thus, in embodiments where the PAEK is a polyetherketoneketone, the difunctional aromatic acid chloride may be phthaloyl dichloride, terephthaloyl dichloride, isophthaloyl dichloride, or mixtures thereof, and the aromatic diether: 1,4-bis(4-phenoxybenzoyl)benzene, 1,3-bis(4-phenoxybenzoyl)benzene, or mixtures thereof.

[0176] The polymerization reaction is preferably carried out in a solvent. The solvent is preferably an aprotic solvent, which can be selected in particular from the list consisting of: dichloromethane, carbon disulfide, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, o-difluorobenzene, 1,2-dichloroethane, 1,1-dichloroethane, 1,1,2,2-tetrachloroethane, tetrachloroethylene, dichloromethane, nitrobenzene, or mixtures thereof. For the production of polyetherketoneketone, o-dichlorobenzene is particularly preferred.

[0177] The polymerization reaction is preferably carried out in the presence of a Lewis acid as catalyst.

[0178] The Lewis acid can be selected in particular from the list consisting of aluminum trichloride, aluminum tribromide, antimony pentachloride, antimony pentafluoride, indium trichloride, gallium trichloride, boron trichloride, boron trifluoride, zinc chloride, iron chloride, tin chloride, titanium tetrachloride and molybdenum pentachloride. For the production of polyetherketoneketone, aluminum trichloride, boron trichloride, aluminum tribromide, titanium tetrachloride, antimony pentachloride, iron chloride, gallium trichloride and molybdenum pentachloride are preferred. For the production of polyetherketoneketone, aluminum trichloride is particularly preferred.

[0179] According to some variants, the polymerization can be carried out in the same reactor as that used for the production of the aromatic diether. However, preferentially, the polymerization is carried out in another reactor.

[0180] The polymerization may be carried out at a temperature ranging, for example, from 20 to 120°C.

[0181] The process for producing PAEK, and in particular polyetherketoneketone, advantageously comprises one or more steps of purifying the polymer, for example the following steps:

[0182] - mixing a polymerization reaction product containing PAEK with a protic solvent to provide a PAEK suspension;

[0183] - Separating the PAEK polymer from the PAEK suspension, preferably by filtering and washing.

[0184] The protic solvent for the PAEK suspension may be, for example, methanol.

[0185] The PAEK polymer can then be recovered from the PAEK suspension by filtration. If desired, the polymer can be washed (preferably with a protic solvent such as methanol) and filtered again one or more times. Washing can be performed, for example, by resuspending the polymer in a solvent.

[0186] Example

[0187] The following examples illustrate the present invention but do not limit it.

[0188] Equipment used for characterization

[0189] For high performance liquid chromatography (HPLC) measurements, a Waters XterraMS C18 3.5 μm 4.6×150 mm column was used and the mobile phase contained the mixture: water / acetonitrile+0.05% trifluoroacetic acid as a gradient. The measurements were performed at 20° C. at a variable wavelength.

[0190] For mass spectrometry (MS) measurements, the machine Waters Xevo G2-XS QT was used with the following parameters:

[0191] Sample introduction via ASAP probe (Atmospheric Pressure Solids Analysis Probe)

[0192] Ionization mode: Positive ASAP

[0193] Mass range: 50-1000m / z

[0194] Source temperature: 120℃

[0195] Corona current: 10μA

[0196] Cone voltage: 50V

[0197] For proton NMR ( 1 H NMR) measurements were performed using Brüker Avance III (500 MHz) and Brüker Neo (600 MHz) spectrometers with CDCl3 as solvent.

[0198] For carbon NMR ( 13C NMR) measurements were performed using Brüker Avance III 500 MHz (125 MHz) and Brüker Neo 600 MHz (150 MHz) spectrometers and CDCl3 as solvent.

[0199] For melting point measurements a Kofler bench and a Gallenkamp melting point apparatus (with capillaries) were used.

[0200] The crude yield is defined hereinafter as the ratio of the number of moles of product obtained at the end of the reaction to the number of moles of dihalogenated compound introduced.

[0201] Hereinafter, the term "purified product yield" means the ratio of the mole number of the purified product (expected product) (i.e., the crude product that has been particularly washed and / or extracted and / or recrystallized) to the mole number of the dihalogenated compound introduced. This yield is related to the purity assessed by NMR (mol %) or by HPLC (mass %).

[0202] Example 1: 1,4-bis(4-fluorobenzoyl)benzene

[0203] Compound A1 of the following formula:

[0204] [Chemical formula 10]

[0205]

[0206] It was synthesized under the following conditions: 1 equivalent (eq.) of terephthaloyl chloride (5 g; 24.6 mmol), 10 equivalents of fluorobenzene (28 g), 2.1 equivalents of AlCl3 (6.9 g; 51.7 mmol). The fluorobenzene used in this reaction was used as both a reagent and a solvent. Under stirring and under an argon atmosphere, aluminum chloride was added to the terephthaloyl chloride dissolved in fluorobenzene in batches (over 10 minutes) at 25°C. At the end of the addition of AlCl3, the reaction mixture was kept stirring at 60°C for 2 hours. After cooling, the obtained product mixture was then poured onto ice water, followed by evaporation of excess fluorobenzene under vacuum on a rotary evaporator. The obtained white solid was filtered out, washed several times with distilled water, 10% aqueous sodium hydroxide, then water, and finally dried under vacuum. The expected product A1 was obtained in a yield of about 99.1%. The crude product was crystallized from dimethylacetamide to obtain a purified product with a yield of about 96% and a purity of> 99.5% (NMR and MS).

[0207] The product was obtained in the form of white crystals which were soluble in chloroform, acetone, dichloromethane and partially soluble in methanol. Its melting point was found to be 220°C.

[0208] Example 2: 1,3-bis(4-fluorobenzoyl)benzene

[0209] Compound A2 of the following formula:

[0210] [Chemical formula 11]

[0211]

[0212] was synthesized in substantially the same manner as Compound A1 of Example 1, except that isophthaloyl dichloride was used instead of terephthaloyl dichloride.

[0213] After a work-up similar to that applied for compound A1, compound A2 was obtained in almost quantitative yield in the form of white crystals with a melting point of 181°C.

[0214] The product is soluble in common solvents. It is crystallized from toluene. The yield obtained is about 95%. According to NMR, MS and HPLC, the purity is about 99.8%.

[0215] Example 3: 1,4-bis(4-chlorobenzoyl)benzene

[0216] Compound A3 of the following formula:

[0217] [Chemical formula 12]

[0218]

[0219] was synthesized in substantially the same manner as Compound A1 of Example 1, except that chlorobenzene was used instead of fluorobenzene.

[0220] Nevertheless, some reaction conditions were modified to provide better yields of the expected product. The reaction conditions were as follows: 1 equivalent of terephthaloyl chloride (5 g; 24.6 mmol), 16 equivalents of chlorobenzene (44.35 g (40 ml), 0.394 mol) and 2.4 equivalents of AlCl (7.88 g, 59.1 mmol). Aluminum chloride was added to terephthaloyl chloride dissolved in chlorobenzene in batches (over 10 minutes) at room temperature under an argon atmosphere with stirring. The chlorobenzene used in this reaction was used as both a reagent and a solvent. At the end of the addition of AlCl, the reaction mixture was stirred at 25 ° C overnight, and then at 90 ° C for 3 hours. After the same treatment as for compound A1, the expected product A3 was obtained in an almost quantitative yield in the form of a white powder. The crude product was crystallized from dimethylacetamide (DMAc) to obtain the pure product in the form of white crystals with a melting point equal to 259 ° C. The yield of the crystalline product was about 96%. High temperature NMR studies show that the selectivity is strictly greater than 99.6%.

[0221] Example 4: 1,3-bis(4-chlorobenzoyl)benzene

[0222] Compound A4 of the following formula:

[0223] [Chemical formula 13]

[0224]

[0225] was synthesized in essentially the same manner as Compound A1 of Example 1, except that chlorobenzene was used instead of fluorobenzene and isophthaloyl dichloride was used instead of terephthaloyl dichloride. Nevertheless, certain reaction conditions were modified as detailed below.

[0226] After adding aluminum chloride in batches to the isophthaloyl chloride dissolved in chlorobenzene at room temperature, the reaction medium was stirred at this temperature for 10 hours and then at 90° C. for 2 hours. After cooling and evaporating excess chlorobenzene, the solid residue obtained was extracted with dichloromethane (DCM). The organic phase was washed with water twice, and washed three times with 10% aqueous sodium hydroxide, and finally washed with water twice. It was then dried and evaporated under vacuum. The expected product in the form of white crystals was obtained, which was pure (purity strictly greater than 99.6%) for NMR and MS and the melting point measured was 215° C. The yield was about 96%.

[0227] Example 5: M1 / M1' mixture from A1 as a dilute reaction mixture (comparative)

[0228] A mixture of phenol (0.718 g; 2 eq.) and potassium carbonate (1.055 g; 2 eq.) was dissolved in the solvent mixture: toluene (10 mL) / NBP (10 mL) and refluxed for 1 hour (bath temperature 130° C.). After addition of compound A1 followed by distillation of toluene, the reaction mixture was heated at 150° C.-160° C. for 2 hours. After treatment of the residue obtained with a water / methanol (95 / 5) mixture, filtration, washing with a water / methanol (95 / 5) mixture and drying, the crude product was obtained in the form of a white powder in a yield of 81%.

[0229] The structure of the expected product, an aromatic diether M1 of the following formula, was confirmed by NMR and mass spectrometry (MS) analysis:

[0230] [Chemical formula 14].

[0231] In the mass spectrum, the presence of a monophenoxy derivative M'1 of the following formula was detected (surface area ratio of about 15%):

[0232] [Chemical formula 15]

[0233]

[0234] The yield of the product crystallized from toluene was about 72% and the purity as measured by NMR was strictly greater than 99%.

[0235] The measured melting point mp is: 208°C.

[0236] Example 6: M2 / M2' mixture from A2 as a dilute reaction mixture (comparative)

[0237] In a similar manner to Example 5, under conditions similar to those described for the synthesis of M1, replacing compound A1 with compound A2, compound M2 of the following formula was obtained from compound A2:

[0238] [Chemical formula 16]

[0239]

[0240] In contrast to Example 5, the reaction mixture in this case was heated at 150-160° C. for only 30 minutes after evaporating the toluene.

[0241] The product was obtained as a white solid in a crude yield of about 70%.

[0242] The structure of the product M2 was confirmed by NMR and mass spectrometry.

[0243] In the mass spectrum, trace amounts of the monophenoxy product M2' (about 15%) of the following formula were detected:

[0244] [Chemical formula 17]

[0245]

[0246] The yield of the product crystallized from methanol was about 61% and the purity as measured by NMR was strictly greater than 99%.

[0247] The measured melting point mp is: 133°C.

[0248] Example 7: M1 from A1 as concentrated solution (invention)

[0249] Under argon, in a sealed tube, phenol (2.5 equivalents) and anhydrous potassium bicarbonate (2.5 equivalents) in powder form were introduced, and then 0.2 mL of N-butyl-2-pyrrolidone (NBP) was introduced. The reaction mixture was heated at 180° C. for 30 minutes under stirring. After partial cooling (about 100° C.), 1 mmol (1 equivalent) of compound A1 was added.

[0250] The reaction mixture was then heated at 205° C. for 2 hours. The progress of the reaction was monitored by HPLC, MS and NMR. This showed that the desired product was converted almost quantitatively 2 hours after the end of the addition of compound A1. In addition, neither the starting product nor the monophenoxy derivative M1′ was detected.

[0251] The residue obtained was worked up by addition of methanol followed by evaporation under vacuum on a rotary evaporator until NBP was removed (azeotrope).

[0252] The crude product obtained in the form of an off-white solid is extracted with chloroform. After filtering off the insolubles and evaporating off the chloroform, the crude product is then crystallized from toluene.

[0253] The pure product M1 (structure confirmed by NMR and MS) was obtained in the form of white crystals in a yield of 83% and a purity strictly greater than 99 mol % as measured by NMR. The melting point was found to be 212° C.

[0254] Example 8: M2 from A2 as concentrated solution (invention)

[0255] In a similar manner to Example 7, under conditions similar to those described for the synthesis of M1, compound M2 was obtained from compound A2, replacing compound A1. A difference relative to Example 7 is that the crude product obtained in the form of an off-white solid was extracted with acetone instead of chloroform in this case. The pure product M2 (structure confirmed by NMR and MS) was obtained in the form of white crystals in 84% yield and with a purity strictly greater than 99% in HPLC. The melting point measured was 133°C.

[0256] Example 11: M1 from A1 and potassium alkoxide as base (invention)

[0257] Phenol (2.3 eq.) and then potassium tert-butoxide (t-BuOK; 2.2 eq.) are introduced into a sealed tube under argon. The reaction medium is heated at 185° C. for 30 minutes with stirring. After partial cooling (about 100° C.), compound A1 (1 eq.) is added.

[0258] The reaction mixture was then heated at 215°C for 2 hours. The progress of the reaction was monitored by HPLC, MS and NMR.

[0259] This showed that the desired product M1 was obtained almost quantitatively within 2 hours after the addition of the compound A1 was completed.

[0260] The residue obtained is worked up by extraction with chloroform.After filtering off the insolubles from the product and evaporating off the chloroform, the crude product is then purified by washing with methanol (and alternatively or additionally crystallizing from toluene).

[0261] The pure product M1 (structure confirmed by NMR and MS) was obtained in the form of white crystals in a yield of about 93% and a purity strictly greater than 99.5% as measured by NMR. The melting point was found to be 212°C.

[0262] Deprotonation of phenol using t-BuOK as base results in the production of tert-butyl alcohol (t-BuOH), which can be used as solvent and facilitates overall conversion. A second advantage of this base is that it allows recovery / recycling of the alcohol by simple distillation at the end of the reaction.

[0263] Example 12: M2 from A2 with potassium alkoxide as base (invention)

[0264] Compound M2 was obtained from Compound A2 in a similar manner to Example 11, substituting Compound A2 for Compound A1 under similar conditions to those described for the synthesis of M1. However, a difference should be noted regarding the work-up step: the crude product was extracted with acetone instead of chloroform.

[0265] The desired product M2 was obtained almost quantitatively within 2 hours after the end of the addition of compound A2 (the progress of the reaction was monitored by NMR).

[0266] The pure product M2 (structure confirmed by NMR and MS) was obtained in the form of white crystals in 92% yield and with a purity strictly greater than 99.5% in HPLC. The melting point was found to be about 132°C-133°C.

[0267] Example 13: M1 / M1" mixture from A3 as a dilute reaction mixture (comparative)

[0268] To synthesize compound M1 from compound A3, the method was carried out essentially as in the reaction of Example 5, wherein A3 replaced A1. The following conditions were used: A3 (1.9 mmol; 1 eq.), phenol (2 eq.) and potassium carbonate (2 eq.). The solvent used was a mixture of toluene (5 mL) / NBP (5 mL).

[0269] The reaction mixture (after distilling off the toluene) was heated at 200°C for 24 hours (instead of 160°C for 2 hours for the fluoro derivative).

[0270] The residue obtained was worked up by addition of methanol followed by evaporation under vacuum on a rotary evaporator until NBP was removed (azeotrope).

[0271] The expected product M1 (about 70%) detected by MS was obtained as a mixture with the starting material and the monophenoxy derivative (surface area ratio of about 15%) M1" of the following formula:

[0272]

[0273] [Chemical formula 18]

[0274] These results show that despite the increased temperature and prolonged heating time, the conversion is still not complete. The expected pure product M1 is obtained after crystallization of the crude product from toluene in a yield of 57% and a purity strictly greater than 99% as measured by NMR. The melting point was found to be 211°C.

[0275] Example 14: M2 / M2" mixture from A4 as a dilute reaction mixture (comparative)

[0276] In a similar manner to Example 13, compound M2 was obtained from compound A4, replacing compound A3, under conditions similar to those described for the synthesis of M1.

[0277] The crude product was obtained as a mixture with trace amounts of the starting material (confirmed by NMR and MS) and the monophenoxy derivative M2 detected by MS of the following formula (area ratio of about 15%):

[0278] [Chemical formula 19]

[0279]

[0280] After crystallization of the crude product from methanol, the pure product M2 (structure confirmed by NMR and MS) was obtained in the form of a white solid in a yield of about 55% and a purity strictly greater than 99%. The recrystallized product had a measured melting point of: 132°C.

[0281] Example 15: M1 from A3 as concentrated solution (invention)

[0282] To synthesize compound M1 from compound A3, the method was carried out in a similar manner to the reaction of Example 7, wherein A3 replaced A1. The following conditions were used: A3 (1 mmol; 1 eq.), phenol (2.8 eq.) and anhydrous potassium bicarbonate (2.8 eq.). The solvent used was NBP (0.2 mL).

[0283] The reaction mixture was heated at 220°C for 3 hours. The reaction progress was monitored by HPLC, MS and NMR. It was shown that the conversion to the desired product was almost quantitative at 3 hours after the addition of compound A3 was completed. The post-treatment of the crude product was carried out in the same manner as in Example 7.

[0284] The pure product M1 (structure confirmed by NMR and MS) was obtained in the form of white crystals in a yield of 82% and a purity strictly greater than 99.5% as measured by NMR. The melting point was found to be 211°C.

[0285] Example 16: M2 from A4 as concentrated solution (invention)

[0286] The procedure was exactly the same as in the case of the synthesis of Example 15, except that A4 replaced A3, the reaction mixture was heated to 210°C instead of 220°C, and the crude product was extracted with acetone instead of chloroform.

[0287] The pure product M2 (structure confirmed by NMR and MS) was obtained in the form of white crystals with a yield of 82% and a purity greater than or equal to 99.5% as measured by NMR. The melting point was found to be 133°C.

[0288] Example 19: M1 from A3 with potassium alkoxide as base (invention)

[0289] Phenol (2.3 eq.) and then t-BuOK (2.2 eq.) are introduced into a sealed tube under argon. The reaction medium is heated at 185° C. for 30 minutes with stirring. After partial cooling (about 100° C.), compound A3 (1 eq.) is added.

[0290] The reaction mixture was then heated at 220° C. for 3 hours. The progress of the reaction was monitored by HPLC and NMR. Thus, it was shown that the desired product M1 was obtained almost quantitatively 3 hours after the end of the addition of compound A3.

[0291] The residue obtained is extracted with chloroform. After filtering off the insolubles and evaporating off the chloroform, the crude product (relatively pure, NMR) is then crystallized from toluene.

[0292] The pure product M1 (structure confirmed by NMR and MS) was obtained in the form of white crystals in a yield of 90% and a purity strictly greater than 99.5% as measured by NMR. The melting point was found to be 212°C.

[0293] Example 20: M2 from A4 with potassium alkoxide as base (invention)

[0294] The procedure was exactly the same as in the case of the synthesis of Example 19, except that A4 replaced A3, the reaction mixture was heated to 205° C. instead of 220° C. and for the work-up step the crude product was extracted with acetone instead of chloroform.

[0295] The desired product M2 was obtained almost quantitatively within 2 hours after the end of the addition of compound A2, which was confirmed by NMR.

[0296] The pure product M2 (structure confirmed by NMR and MS) was obtained in the form of white crystals in a yield of 90% and a purity strictly greater than 99.5% as measured by HPLC. The melting point was found to be 132°C.

[0297] Examples 21-24: Alkoxide Counterion t-BuO - Impact

[0298] Experiments similar to those of Examples 11, 12, 19 and 20 were performed, wherein t-BuONa was used instead of t-BuOK. They are referred to as Examples 21, 22, 23 and 24, respectively. The reaction time and reaction temperature were adjusted to obtain an almost quantitative conversion. The conditions used and the results obtained are collated in the following Table 1:

[0299] [Table 1]

[0300] Temperature(℃) Reaction time (h) Yield of purified product Embodiment 21 220 4 >90 Embodiment 22 210 3 >90 Embodiment 23 225 20 >90 Embodiment 24 225 20 >90

[0301] Thus, comparison of Examples 11, 12, 19 and 20 relative to Examples 21, 22, 23 and 24 shows that the reaction with t-BuOK is much faster kinetically than the reaction with t-BuONa, the reaction being carried out in t-BuOH / excess phenol serving as solvent.

[0302] Example 25: M1 from A1 with potassium alkoxide as base and removal of alcohol prior to reaction

[0303] Phenol (2.3 eq.) and t-BuOK (2.2 eq.) were introduced into a sealed tube under argon. The reaction medium was heated at 185° C. (bath temperature) for 30 minutes. After partial cooling (to about 100° C.), the t-BuOH formed as a by-product and excess phenol were removed by evaporation using a nitrogen or argon stream. Compound A1 was then added.

[0304] After all of the compound A1 had been added, the reaction mixture was heated at 230° C. (bath temperature) for 1 hour. From T=210° C. (bath temperature), it was noted that the reaction medium turned into a light brown, easily stirrable suspension.

[0305] The progress of the reaction was monitored by NMR. It was thus possible to show that the conversion to the expected product M1 was complete one hour after the end of the addition of compound A1.

[0306] After cooling, the crude product formed in the form of a light brown solid was scraped off and then ground. In order to remove the salt formed and any traces of phenol, the crude product obtained was stirred in distilled water (20 mL) for 1 hour, and then filtered and washed several times with distilled water and finally pentane. After drying in a baking oven at 75° C. for 2 hours, the expected product M1 in the form of an off-white powder was obtained with a yield of 94% and an NMR purity strictly greater than 99.5%.

[0307] Example 26: M1 from A3 with potassium alkoxide as base and removal of alcohol prior to reaction

[0308] Phenol (2.3 eq.) and t-BuOK (2.2 eq.) were introduced into a sealed tube. The reaction mixture was heated at 185° C. (bath temperature=185° C.) for 30 minutes. After partial cooling (to about 100° C.), the t-BuOH formed as a by-product and excess phenol were removed by evaporation using a nitrogen or argon stream. Compound A3 was then added.

[0309] After all the addition of compound A3, the reaction mixture was heated at 230°C for 4 hours. The progress of the reaction was monitored by NMR. Thus, it was shown that the conversion was complete 4 hours after the addition of compound A3 was completed.

[0310] After cooling, the crude product formed in the form of a brown solid was stirred in distilled water (30 mL) for 6 hours. The resulting suspension was filtered and then washed several times with distilled water. After drying in an oven at 85° C. for 6 hours, the expected product M1 in the form of an off-white powder was obtained with an excellent yield of about 93%, and a purity measured by NMR of strictly greater than 99.3%.

[0311] Example 27: M2 from A2 with potassium alkoxide as base and removal of alcohol prior to reaction

[0312] The method was carried out exactly the same as in the case of the synthesis of Example 26, except that A2 replaced A3. The experiment was carried out under the following conditions: A2 (3 mmol; 1 eq.); t-BuOK (0.748 g; 2.2 eq.); phenol (0.652 g; 2.3 eq.). After work-up using the method described in Example 26, compound M2 was obtained with a yield of about 97% and a purity measured by NMR strictly greater than 99.6%.

[0313] Example 28: M1 from A1 with sodium alkoxide as base and removal of alcohol prior to reaction

[0314] The experiment was carried out under the following conditions: HAr53 (3 mmol; 0.976 g; 1 eq.); t-BuONa (2.2 eq.); phenol (2.3 eq.). Phenol (2.3 eq.) and t-BuONa (2.2 eq.) were introduced into a reactor equipped with a cold finger and a pressure gauge. The reaction medium was heated at 185° C. (bath temperature) for 30 minutes (internal temperature 140° C.; internal pressure 2.7 bar (pressure relative to atmospheric pressure). After partial cooling (to about 100° C.), t-BuOH formed as a by-product and excess phenol were removed by evaporation using a nitrogen stream. Compound A1 was then added.

[0315] After all the compound A1 was added, the reaction mixture was heated at 230° C. (bath temperature 230° C.; internal temperature 190° C.; internal pressure 0.25 bar) for 2 hours. It was noted that from an internal temperature of 170° C., the reaction mixture was in the form of a clear brown liquid and was therefore easy to stir. The progress of the reaction was monitored by NMR. This demonstrated that the conversion to the expected product M1 was completed within 2 hours after the end of the A1 addition.

[0316] After cooling, the crude product formed in the form of a brown solid was stirred in distilled water (30 mL) for 6 hours. The resulting suspension was filtered and then washed several times with distilled water. After drying in an oven at 85° C. for 6 hours, the expected product M1 in the form of an off-white powder was obtained in a yield of 96% and a purity measured by NMR strictly greater than 99.4%.

[0317] By comparing Examples 19 and 28, it can be concluded that in the absence of t-BuOH / excess phenol solvent, the reaction proceeds just as well with t-BuONa as with t-BuOK.

[0318] Example 29: M1 from A3 with sodium metal as base

[0319] Phenol (0.58 g; 2.2 eq.) and then dried THF (3 mL) were introduced into a reactor equipped with a cold finger and a thermometer. Sodium (2.2 eq.) was then added in batches at 25 ° C under vigorous stirring. Hydrogen evolution was observed. The reaction medium was stirred at 25 ° C until the sodium completely disappeared, which took about 1 hour. THF was then removed by evaporation by heating the reaction medium to 60 ° C under a nitrogen stream. After cooling, compound A3 was added.

[0320] After all the addition of compound A3, the reaction mixture was heated at 230° C. (bath temperature) for 5 hours. It should be noted that from the measured internal temperature (temperature of the reaction mixture) of 190° C., the reaction medium became a stirrable dark yellow liquid.

[0321] The progress of the reaction was monitored by NMR. It was shown that the conversion to the expected product M1 was about 65% within 2 hours after the addition of compound A3 was complete and almost complete within 5 hours after the addition of compound A3 was complete.

[0322] After cooling, the crude product obtained as a brown solid was stirred in distilled water (30 mL) for 3 hours. The resulting suspension was filtered and then washed several times with distilled water. After drying in an oven at 85° C. for 6 hours, the expected product M1 in the form of an off-white powder was obtained with a yield of 90% and a purity measured by NMR strictly greater than 99.3%.

[0323] Examples 30-32: M1 from A3 as concentrated solution in DPS and potassium alkoxide as base

[0324] In a sealed tube, phenol (2.4 eq.), anhydrous potassium carbonate in powder form (2.3 eq.), monomer A3 (1 eq., 0.2 g) and then diphenyl sulfone (DPS) (2.03 eq.) in the form of a white solid were introduced under argon. The reaction mixture was heated at 230° C. for 5 hours with stirring. After only 25 minutes, the reaction mixture became a dark red, easily stirred suspension. The progress of the reaction was monitored by NMR.

[0325] After cooling, the product obtained in the form of a white to off-white solid was purified by first washing with acetone to remove DPS and excess phenol, followed by a second washing with distilled water to remove the salts formed: in particular KCl and excess potassium phenolate. After drying in an oven at 75° C. for 2 hours, the expected monomer M1 was obtained in the form of a white powder, NMR pure (>99%), in a yield of 96%.

[0326] It should be noted that the diphenyl sulfone used was only technical grade (Sigma-Aldrich; purity strictly greater than 97%).

[0327] For Examples 31 and 32, the process was carried out exactly as in the case of the synthesis of Example 30, using different ratios of the starting compounds.

[0328] In Example 31, phenol (2.4 eq.), anhydrous potassium carbonate in powder form (2.3 eq.), monomer A3 (1 eq., 0.2 g) and then diphenyl sulfone (DPS) in the form of a white solid (4.07 eq.) were introduced into a sealed tube under argon.

[0329] After two successive washings and drying, the expected monomer M1 was obtained in the form of a white powder, NMR pure (>99%), in a yield of 97%.

[0330] In Example 32, phenol (2.3 eq.), anhydrous potassium carbonate in powder form (2.2 eq.), monomer A3 (1 eq., 0.2 g) and then diphenyl sulfone (DPS) in the form of a white solid (4.07 eq.) were introduced into a sealed tube under argon.

[0331] After two successive washings and drying, the expected monomer M1 was obtained in the form of a white powder, NMR pure (>99%), in a yield of 96%.

Claims

1. A method for producing an aromatic diether, comprising: reacting a compound A comprising at least two halogenated aromatic groups with a compound B, optionally in the presence of a compound C serving as a reaction solvent, B being an aromatic alkoxide, The molar ratio of compound B to compound A is at least 2:1 and the molar ratio of compound C to compound A is less than or equal to 3:1, Wherein compound C is selected from the list consisting of: C1-C6-alkyl-2-pyrrolidone; sulfoxide; sulfone; nitrile; N,N-dimethylamide; and mixtures thereof.

2. The method of claim 1, wherein compound A is a compound having the following chemical formula: X 1 Ar-[Z i Ar i ] n X 2 (II), in, - i is an integer ranging from 1 to 3, and n is an integer equal to 0 or 1; -X1 and X2 independently represent a halogen atom; -For any i of Ar i and Ar independently represents a substituted or unsubstituted divalent aromatic group; as well as -For any i, Z i independently represent an oxygen atom, a sulfur atom, an alkylene group, a carbonyl group or a sulfonyl group.

3. The manufacturing method as claimed in claim 2, wherein: In the chemical formula (II): -i is equal to 2 and n is equal to 1; - X1 and X2 both represent a chlorine atom or a fluorine atom; -Ar and Ar2 both represent 1,4-phenylene groups; -Ar1 represents a 1,3-phenylene or 1,4-phenylene group; and -Z1 and Z2 both represent a carbonyl group.

4. The method of claim 1 , wherein compound B has the chemical formula: Ar-O - (III), in, Ar' represents a substituted or unsubstituted monovalent aromatic group.

5. The method according to any one of claims 1 to 3, wherein compound B is a phenolate.

6. The production method according to any one of claims 1 to 3, wherein the molar ratio of compound B to compound A is less than or equal to 3:

1.

7. The production method as claimed in any one of claims 1 to 3, wherein compound B is obtained by deprotonating an aromatic alcohol B", i.e., a conjugate acid of an aromatic alcohol salt B, in situ or ex situ with a base that reacts with B" to obtain compound B.

8. The method of claim 7, wherein the base to be reacted with B" is a linear or branched alcohol salt containing 3 to 10 carbon atoms.

9. The method of claim 7, wherein the base reacting with B" is a carbonate.

10. The production method as claimed in claim 7, wherein the base reacting with B" is an alkali metal salt.

11. The method of claim 7, wherein the base to be reacted with B" is sodium metal or potassium metal.

12. The production method as claimed in claim 7, wherein the molar ratio of the base reacting with B" relative to B" is less than or equal to 1:

1.

13. The production process as claimed in any one of claims 1 to 3, wherein compound C has a polarity measured at 20°C of greater than or equal to 3 Debye.

14. The production method as claimed in any one of claims 1 to 3, wherein compound A reacts with compound B in the absence of any solvent.

15. The production method as claimed in any one of claims 1 to 3, wherein compound A reacts with compound B in a molten form.

16. The production method as claimed in claim 2, wherein in formula (II), X1 and X2 represent the same halogen atom.

17. The production method as claimed in claim 16, wherein in formula (II), both X1 and X2 represent chlorine or fluorine.

18. The method of manufacturing as claimed in claim 2, wherein in formula (II), for any i, Ar i and Ar independently represents a divalent aromatic group selected from the list consisting of 1,3-phenylene, 1,4-phenylene, divalent 1,1'-biphenylene at 4,4' positions, divalent 1,1'-biphenylene at 3,4' positions, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene.

19. The method of manufacturing as claimed in claim 18, wherein in formula (II), for any i of Ar i and Ar independently represents 1,3-phenylene and 1,4-phenylene.

20. The production method as claimed in claim 2, wherein the alkylene group is -CH2- or -C(CH3)2-.

21. The method of manufacturing as claimed in claim 2, wherein in formula (II), Z i independently represents an oxygen atom or a carbonyl group.

22. The method of manufacturing as claimed in claim 21, wherein in formula (II), Z i independently represents a carbonyl group.

23. The production method as claimed in claim 4, wherein in formula (III), Ar' represents a monovalent aromatic group selected from the list consisting of a phenyl group, a monovalent biphenyl group and a naphthyl group.

24. The method of claim 6, wherein the molar ratio of compound B to compound A is less than or equal to 2.5:

1.

25. The method of claim 6, wherein the molar ratio of compound B to compound A is less than or equal to 2.3:

1.

26. The method of claim 6, wherein the molar ratio of compound B to compound A is 2:

1.

27. The manufacturing method as claimed in claim 7, wherein the base is selected from the list consisting of aromatic or aliphatic alcoholates, carbonates, metal hydrides and alkali metals.

28. The manufacturing method as claimed in claim 8, wherein the base is selected from the list consisting of the following salts: isopropoxide, 1,2-dimethylpropoxide, 1,1-dimethylpropoxide, 2,2-dimethylpropoxide, 1,1,2-trimethylpropoxide, 1,2,2-trimethylpropoxide, 1-ethyl-2-methylpropoxide, 1-ethylpropoxide, n-butoxide, isobutoxide, sec-butoxide, tert-butoxide, 2-methylbutoxide, 3-methylbutoxide, 1,2-dimethylbutoxide, 1,3-dimethylbutoxide, 2,3-dimethylbutoxide, 1,1-dimethyl butoxide, 2,2-dimethylbutoxide, 3,3-dimethylbutoxide, 1-ethylbutoxide, 2-ethylbutoxide, 1-propylbutoxide, 1,1,3,3-tetramethylbutoxide, n-pentoxide, 2-pentoxide, 2-methylpentoxide, n-hexoxide, 2-hexoxide, 3-methylpentoxide, 4-methylpentoxide, 2-ethylpentoxide, 2-ethylhexoxide, 2-propylhepoxide, n-hepoxide, 2-hepoxide, 3-hepoxide, n-octoxide and mixtures thereof.

29. The manufacturing method as claimed in claim 28, wherein the base is selected from the list of salts consisting of isopropoxide, n-butoxide, tert-butoxide, n-hepoxide, n-octoxide and mixtures thereof.

30. The method of claim 10, wherein the base reacted with B" is a sodium salt, a potassium salt or a mixture of a sodium salt and a potassium salt.

31. The method of claim 11, wherein the base reacting with B" is sodium metal.

32. The manufacturing method as claimed in claim 13, wherein compound C has a polarity measured at 20°C of greater than or equal to 3.5 Debye.

33. The production method as described in any one of claims 1 to 3, wherein the C1-C6-alkyl-2-pyrrolidone is N-methyl-2-pyrrolidone or N-butyl-2-pyrrolidone.

34. The production method as claimed in any one of claims 1 to 3, wherein the sulfoxide is dimethyl sulfoxide or diethyl sulfoxide.

35. The production method as claimed in any one of claims 1 to 3, wherein the sulfone is dimethyl sulfone, diethyl sulfone, diisopropyl sulfone, diphenyl sulfone or tetramethylene sulfone.

36. The production method according to any one of claims 1 to 3, wherein the nitrile is acetonitrile, propionitrile or benzonitrile.

37. The production method as claimed in any one of claims 1 to 3, wherein the N,N-dimethylamide is N,N-dimethylacetamide or N,N-dimethylformamide.

38. A process as claimed in any one of claims 1 to 3, wherein compound C is diphenyl sulfone.

39. A method for producing a polyaryletherketone polymer, comprising: Producing an aromatic diether as described in any one of claims 1 to 38; The aromatic diether is reacted with a compound D comprising at least two acid chloride groups.

40. The method of claim 39, wherein compound D is a compound having the following formula: ClC(O)-Ar-[Z j The j ] m -C(O)Cl(IV), in, j is an integer ranging from 1 to 3 and m is an integer equal to 0 or 1; For any j, Ar j and Ar independently represents a substituted or unsubstituted divalent aromatic group; and For any j, Zj independently represents an oxygen atom, a sulfur atom, an alkylene group, or a sulfone.

41. A method as claimed in any one of claims 39 and 40, wherein: - the aromatic diether is selected from the list consisting of: or a mixture thereof; - The compound D is selected from the following list of compounds: or a mixture thereof.

42. The method of claim 40, wherein in formula (IV), for any j, Ar j and Ar independently represents a divalent aromatic group selected from the list consisting of 1,3-phenylene, 1,4-phenylene, divalent 1,1'-biphenylene at 4,4' positions, divalent 1,1'-biphenylene at 3,4' positions, 1,4-naphthylene, 1,5-naphthylene and 2,6-naphthylene.

43. The method of claim 40, wherein the alkylene group is -CH2- or -C(CH3)2-.

44. A method as claimed in claim 40, wherein Zj represents an oxygen atom.

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