Compositions comprising hydroquinone and catechol, methods for preparing these compositions

Abstract

The present invention relates to compositions comprising hydroquinone and catechol, methods for preparing these compositions. In particular, compositions comprising at least one compound selected from the group consisting of hydroquinones and catechols are described. Another aspect of the invention relates to a process for the preparation of a composition according to the invention comprising at least one compound selected from the group consisting of hydroquinones and catechols.

Description

[0001] This application is a divisional application of the following application: Application date June 12, 2018; Application number 2018800397737; Invention name “Compositions containing hydroquinone and catechol, and methods for preparing these compositions”. Technical Field

[0002] The present invention relates to compositions comprising hydroquinone and / or catechol and to a process for preparing these compositions by hydroxylating phenol. Background Art

[0003] Aromatic hydroxylated compounds are important compounds in organic synthesis. Various routes for synthesizing these products have been developed over time, particularly through the hydroxylation of phenol in the presence of a catalyst. The hydroxylation reaction of phenol results in the production of two isomers: 1,4-dihydroxybenzene or hydroquinone (HQ) and 1,2-dihydroxybenzene or catechol (PC), compounds with high industrial potential. Hydroquinone is used in many applications as a polymerization inhibitor in elastomers, an antioxidant, or as a synthesis intermediate. Another application area is photography. Catechol itself is a widely used product, particularly as an intermediate in the synthesis of molecules used in various applications such as the pharmaceutical, agrochemical, fragrance, and food industries. WO 1998 / 02500 describes compositions comprising at least one catechol derivative, an aromatic solvent, and an alcohol. These compositions are used as polymerization inhibitors. They remain liquid at temperatures as low as -50°C, thus avoiding the need for thermostatically controlled industrial lines.

[0004] In view of this broad field of development, there is a need to produce these products on an industrial scale and to have optimized manufacturing methods available.

[0005] Conventionally, hydroquinone and catechol are produced by hydroxylation of phenol with hydrogen peroxide in the presence of an acid catalyst, a strong protic acid (for example in FR 2 071 464) or another solid catalyst having acidic properties, such as, for example, zeolite TS-1 (FR 2 489 816), zeolites of the MEL titanium silicalite type (EP 1 131 264), titanium zeolites of the MFI type (EP 1 123 159) or also zeolite MCM-22 (FR 2 856 681).

[0006] One of the challenges of these methods is to optimize the productivity of the reaction in a general way so that the demand for hydroquinone and catechol can be met. In particular, the optimized parameter can be the yield of the reaction, the ratio of hydroquinone to catechol or the energy efficiency of the reaction.

[0007] In order to cope with this general productivity problem, many documents report specific reaction conditions.For example, the property of a kind of solvent or multiple solvents for reaction is by people such as Thangaraj, Indian Journal of Chemistry, volume 33A, March 1994, in the scientific publication of page 255-258, and also in patent application EP 3048091 and in patent US 5426244, is described.

[0008] At the end of this hydroxylation reaction, a mixture is generally obtained comprising hydroquinone and catechol in variable proportions, as well as various by-products such as resorcinol, pyrogallol, etc. To the best of the inventors' knowledge, the formation of undesirable by-products derived from the solvent or solvents has never been studied in the context of phenol hydroxylation reactions. In fact, the presence of these by-products can have an impact on the efficiency of the reaction itself and also on the subsequent purification process. Summary of the Invention

[0009] It is commendable that the applicant company has identified novel hydroquinone and / or catechol compositions containing certain by-products, the nature and amount of which are controlled.

[0010] Therefore, a first subject of the present invention is a composition comprising at least one compound selected from hydroquinone and catechol, characterized in that the composition additionally contains between 0.1 and 10,000 ppm of at least one compound selected from the group consisting of 2-(alkoxy)phenol, 4-(alkoxy)phenol, 2-(alkyl)phenol, 4-(alkyl)phenol, (alkyl)catechol, (alkyl)hydroquinone and alkoxybenzene.

[0011] Preferably, the subject of the present invention is a composition comprising at least one compound chosen from hydroquinone and catechol, characterized in that the composition additionally comprises between 0.1 and 10 000 ppm of at least one compound chosen from the group consisting of 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, 2-(tert-butyl)phenol, 4-(tert-butyl)phenol, (tert-butyl)catechol, (tert-butyl)hydroquinone and tert-butoxybenzene.

[0012] According to another aspect, the present invention provides a composition comprising at least one compound chosen from hydroquinone and catechol, characterized in that the composition additionally comprises between 0.1 and 10 000 ppm of at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, 2-isopropylphenol, 4-isopropylphenol, isopropylcatechol, isopropylhydroquinone and cumene.

[0013] Another aspect of the present invention relates to a process for preparing a composition according to the invention comprising at least one compound chosen from hydroquinone and catechol, characterized in that the process comprises a step (a) of reacting phenol with hydrogen peroxide in the presence of a catalyst in a solvent comprising an alcohol or a mixture of alcohols preferably chosen from isopropanol, 2,2-dimethylpropanol and tert-butanol. DETAILED DESCRIPTION

[0014] In the context of the present invention, and unless stated otherwise, the expressions "between ..." include the limit values. Unless stated otherwise, percentages and ppm are percentages and ppm by weight.

[0015] In the context of the present invention, and unless stated otherwise, the expression "alkyl" denotes a straight or branched chain containing from 1 to 6 carbon atoms.

[0016] In the context of the present invention, and unless stated otherwise, the expression "alkoxy" denotes an alkyl group bonded to an oxygen atom: RO.

[0017] In the context of the present invention, and unless otherwise specified, the term “ppm” means “parts per million.” This unit represents a fraction by weight: 1 ppm = 1 mg / kg.

[0018] A first aspect of the present invention is a composition comprising at least one compound selected from hydroquinone and catechol, characterized in that the composition additionally comprises between 0.1 and 10,000 ppm of at least one compound selected from the group consisting of 2-(alkoxy)phenol, 4-(alkoxy)phenol, 2-(alkyl)phenol, 4-(alkyl)phenol, (alkyl)catechol, (alkyl)hydroquinone and alkoxybenzene.

[0019]

[0020] Preferably, the composition comprising at least one compound chosen from hydroquinone and catechol is characterized in that it additionally comprises at least one compound chosen from 2-(alkoxy)phenol, 4-(alkoxy)phenol, 2-(alkyl)phenol, 4-(alkyl)phenol, (alkyl)catechol and (alkyl)hydroquinone in an amount of:

[0021] - greater than or equal to 0.5 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm; and / or

[0022] - less than or equal to 500 ppm, preferably in an amount less than or equal to 300 ppm and still more preferably in an amount less than or equal to 100 ppm.

[0023] Furthermore, the composition according to the invention may contain alkoxybenzenes in an amount greater than or equal to 1 ppm, preferably greater than or equal to 10 ppm and even more preferably greater than or equal to 100 ppm. The composition according to the invention may additionally contain alkoxybenzenes in an amount less than or equal to 10,000 ppm, preferably less than or equal to 5,000 ppm and even more preferably less than or equal to 1,000 ppm.

[0024] According to a particular aspect, the composition according to the invention does not comprise aromatic agents.

[0025] In the context of the present invention, it is also possible that derivatives of the dialkoxylated, dialkylated or alkylated and alkoxylated type are to be formed during the reaction. Mention may be made, without being limited thereto, of derivatives of the 2,3-dialkoxyphenol, 2,6-dialkoxyphenol, 2,3-dialkylphenol, 2,6-dialkylphenol, 2-alkoxy-6-alkylphenol or 2-alkoxy-3-alkylphenol type.

[0026] Advantageously, the subject of the present invention is a composition comprising at least one compound chosen from hydroquinone and catechol, characterized in that the composition additionally contains between 0.1 and 10 000 ppm of at least one compound chosen from the group consisting of 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, 2-(tert-butyl)phenol, 4-(tert-butyl)phenol, (tert-butyl)catechol, (tert-butyl)hydroquinone and tert-butoxybenzene.

[0027]

[0028] Preferably, the composition comprising at least one compound chosen from hydroquinone and catechol is characterized in that it additionally comprises at least one compound chosen from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, 2-(tert-butyl)phenol, 4-(tert-butyl)phenol, (tert-butyl)catechol and (tert-butyl)hydroquinone in an amount of:

[0029] - greater than or equal to 0.5 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm; and / or

[0030] - less than or equal to 500 ppm, preferably in an amount less than or equal to 300 ppm and still more preferably in an amount less than or equal to 100 ppm.

[0031] Furthermore, the composition according to the invention may contain tert-butoxybenzene in an amount greater than or equal to 1 ppm, preferably greater than or equal to 10 ppm and even more preferably greater than or equal to 100 ppm. The composition according to the invention may additionally contain tert-butoxybenzene in an amount less than or equal to 10,000 ppm, preferably less than or equal to 5,000 ppm and even more preferably less than or equal to 1,000 ppm.

[0032] Advantageously, the subject of the present invention is a composition comprising at least one compound chosen from hydroquinone and catechol, characterized in that the composition additionally contains between 0.1 and 10 000 ppm of at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, 2-isopropylphenol, 4-isopropylphenol, isopropylcatechol, isopropylhydroquinone and cumene.

[0033]

[0034] Preferably, the composition comprising at least one compound chosen from hydroquinone and catechol is characterized in that it additionally comprises at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, 2-isopropylphenol, 4-isopropylphenol, isopropylcatechol and isopropylhydroquinone in an amount of:

[0035] - greater than or equal to 0.5 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm; and / or

[0036] - less than or equal to 500 ppm, preferably in an amount less than or equal to 300 ppm and still more preferably in an amount less than or equal to 100 ppm.

[0037] Furthermore, the composition according to the invention may contain cumene in an amount greater than or equal to 1 ppm, preferably greater than or equal to 10 ppm and even more preferably greater than or equal to 100 ppm. The composition according to the invention may additionally contain cumene in an amount less than or equal to 10 000 ppm, preferably less than or equal to 5000 ppm and even more preferably less than or equal to 1000 ppm.

[0038] One aspect of the present invention relates to a composition comprising:

[0039] - at least 80% hydroquinone, preferably at least 90% hydroquinone, more preferably at least 99% hydroquinone, and

[0040] - at least one compound selected from 2-(alkoxy)phenol, 4-(alkoxy)phenol, (alkyl)catechol and (alkyl)hydroquinone in an amount greater than or equal to 0.1 ppm, preferably greater than or equal to 1 ppm and still more preferably greater than or equal to 10 ppm.

[0041] Advantageously, the amount of at least one compound chosen from 2-(alkoxy)phenol, 4-(alkoxy)phenol, (alkyl)catechol and (alkyl)hydroquinone may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and even more preferably less than or equal to 100 ppm.

[0042] According to another aspect, the present invention relates to a composition comprising:

[0043] - at least 80% catechol, preferably at least 90% catechol, more preferably at least 99% catechol, and

[0044] at least one compound chosen from 2-(alkyl)phenol and 4-(alkyl)phenol in an amount greater than or equal to 0.1 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm.

[0045] Advantageously, the amount of at least one compound chosen from 2-(alkyl)phenol and 4-(alkyl)phenol may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and even more preferably less than or equal to 100 ppm.

[0046] Advantageously, the present invention relates to a composition comprising:

[0047] - at least 80% hydroquinone, preferably at least 90% hydroquinone, more preferably at least 99% hydroquinone, and

[0048] - at least one compound selected from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, (tert-butyl)catechol and (tert-butyl)hydroquinone in an amount greater than or equal to 0.1 ppm, preferably greater than or equal to 1 ppm and still more preferably greater than or equal to 10 ppm.

[0049] Advantageously, the amount of at least one compound chosen from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, (tert-butyl)catechol and (tert-butyl)hydroquinone may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and even more preferably less than or equal to 100 ppm.

[0050] According to another aspect, the present invention relates to a composition comprising:

[0051] - at least 80% catechol, preferably at least 90% catechol, more preferably at least 99% catechol, and

[0052] at least one compound selected from 2-(tert-butyl)phenol and 4-(tert-butyl)phenol in an amount greater than or equal to 0.1 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm.

[0053] Advantageously, the amount of at least one compound chosen from 2-(tert-butyl)phenol and 4-(tert-butyl)phenol may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and more preferably still less than or equal to 100 ppm.

[0054] Advantageously, the present invention relates to a composition comprising:

[0055] - at least 80% hydroquinone, preferably at least 90% hydroquinone, more preferably at least 99% hydroquinone, and

[0056] - at least one compound selected from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, isopropylcatechol and isopropylhydroquinone in an amount greater than or equal to 0.1 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm.

[0057] Advantageously, the amount of at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, isopropylcatechol and isopropylhydroquinone may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and more preferably still less than or equal to 100 ppm.

[0058] According to another aspect, the present invention relates to a composition comprising:

[0059] - at least 80% catechol, preferably at least 90% catechol, more preferably at least 99% catechol, and

[0060] at least one compound chosen from 2-isopropylphenol and 4-isopropylphenol in an amount greater than or equal to 0.1 ppm, preferably in an amount greater than or equal to 1 ppm and still more preferably in an amount greater than or equal to 10 ppm.

[0061] Advantageously, the amount of at least one compound chosen from 2-isopropylphenol and 4-isopropylphenol may be less than or equal to 1000 ppm, preferably less than or equal to 500 ppm and more preferably still less than or equal to 100 ppm.

[0062] The compositions that are the subject of the present invention are particularly advantageous because they respond to the need to control industrial processes. The presence and content of the mentioned by-products are compatible, on the one hand, with a process for the hydroxylation of phenol with high productivity, providing a large operating window for the production of PC and HQ, and, on the other hand, with purification processes, which make it possible to control the overall costs of the process.

[0063] Another aspect of the present invention relates to a process for preparing a composition according to the invention comprising at least one compound chosen from hydroquinone and catechol, characterized in that the process comprises a step (a) of reacting phenol with hydrogen peroxide in the presence of a catalyst in a solvent comprising an alcohol or a mixture of alcohols preferably chosen from isopropanol, 2,2-dimethylpropanol and tert-butanol.

[0064] Step (a) corresponds to the hydroxylation of phenol. This method allows the synthesis of hydroquinone (HQ) and catechol (PC). Advantageously, the method according to the invention allows the PC / HQ ratio to be controlled. The PC / HQ molar ratio is less than or equal to 1, preferably less than or equal to 0.7.

[0065] The hydrogen peroxide (H2O2) used in the present invention can be in an aqueous solution. Any dilution of H2O2 in water can be used. In the context of this method, a typical concentration of 30% in water can be used, but aqueous solutions exhibiting higher concentrations in water can also be used as is or diluted with an inert solvent, which can be selected from an alcohol, preferably methanol, ethanol, isopropanol, butanol, or tert-butanol. The hydrogen peroxide can be added all at once. The hydrogen peroxide can also be added to the reaction in portions over a given period of time.

[0066] According to the method of the present invention, the reaction is carried out in the presence of a catalyst, preferably a heterogeneous catalyst. The catalyst can be a titanium-containing zeolite. These zeolites can exhibit structures of the MFI family or the MEL family. The catalyst can be a titanium silicate molecular sieve. The composition of the titanium silicate molecular sieve according to the present invention can be represented by the following structure: (SiO2) x (TiO2) (1-x) The value of x / (1-x) can be between 5 and 1000, preferably between 10 and 500. Titanium silicate molecular sieves can be prepared according to methods known to those skilled in the art; for example, the method described in US Pat. No. 4,410,501 can be mentioned. The catalyst can preferably be TS-1, TS-2, Ti-MWW, or Ti-MCM68; more preferably, the catalyst is TS-1.

[0067] The amount of catalyst used in the present invention is generally greater than or equal to 0.1% by weight, preferably greater than or equal to 0.4% by weight, relative to phenol. The amount of catalyst used in the present invention is generally less than or equal to 30% by weight, preferably less than or equal to 20% by weight.

[0068] In the method according to the present invention, the solvent comprises an alcohol or a mixture of alcohols; preferably, the alcohol is selected from isopropanol, 2,2-dimethylpropanol and tert-butanol. The alcohol can be used alone or in combination with a co-solvent. The co-solvent can advantageously be selected from water.

[0069] Advantageously, the ratio by weight of alcohol to co-solvent used in the reaction may be between 1 :99 and 90:10, preferably between 3:97 and 80:20.

[0070] The amount of alcohol used is between 1 and 90% by weight, preferably between 3 and 50% by weight, relative to the total weight of the liquid in the reaction.

[0071] The amount of water used can be the amount of water contributed by the aqueous hydrogen peroxide solution. The amount of co-solvent is between 5% and 90% by weight, preferably between 8% and 90% by weight, more preferably between 8% and 85% by weight, relative to the total weight of the liquid in the reaction.

[0072] Preferably, in the process according to the present invention, the solvent comprises tert-butanol. Tert-butanol can be used alone or in combination with a co-reagent. The co-reagent can advantageously be selected from water, acetone, acetonitrile, 1,4-dioxane or an alcohol of formula R'-OH, or a mixture thereof, wherein R' represents a linear or branched alkyl chain containing from 1 to 6 carbon atoms; preferably, the alcohol is selected from methanol, ethanol, isopropanol, n-propanol and n-butanol. Advantageously, the ratio by weight of tert-butanol to co-solvent used in the reaction can be between 1:99 and 90:10, preferably between 3:97 and 80:20.

[0073] The amount of tert-butanol used is between 1 and 90% by weight, preferably between 3 and 50% by weight, relative to the total weight of the liquid in the reaction.

[0074] The amount of water used can be the amount of water contributed by the aqueous hydrogen peroxide solution. The amount of co-solvent is between 5% and 90% by weight, preferably between 8% and 90% by weight, more preferably between 8% and 85% by weight, relative to the total weight of the liquid in the reaction.

[0075] The reaction temperature may be greater than or equal to 30° C., preferably greater than or equal to 40° C. The reaction temperature may be less than or equal to 130° C., preferably less than or equal to 100° C.

[0076] The process can be carried out continuously, semi-continuously or batchwise.

[0077] At the end of step (a), it is advantageously possible to obtain a composition according to the invention comprising at least one compound chosen from hydroquinone and catechol, characterised in that it additionally comprises between 0.1 and 10 000 ppm of at least one compound chosen from 2-(alkoxy)phenol, 4-(alkoxy)phenol, 2-(alkyl)phenol, 4-(alkyl)phenol, (alkyl)catechol, (alkyl)hydroquinone and alkoxybenzene.

[0078] Preferably, at the end of step (a), it is possible to advantageously obtain a composition according to the invention comprising at least one compound chosen from hydroquinone and catechol, characterized in that this composition additionally contains between 0.1 and 10 000 ppm of at least one compound chosen from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, 2-(tert-butyl)phenol, 4-(tert-butyl)phenol, (tert-butyl)catechol, (tert-butyl)hydroquinone and tert-butoxybenzene.

[0079] Preferably, at the end of step (a), it is possible to advantageously obtain a composition according to the invention comprising at least one compound chosen from hydroquinone and catechol, characterized in that this composition additionally contains between 0.1 and 10 000 ppm of at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, 2-isopropylphenol, 4-isopropylphenol, isopropylcatechol, isopropylhydroquinone and cumene.

[0080] According to one embodiment of the present invention, the method described above may additionally include a step (b) of purifying the composition obtained in step (a). The choice of purification method is not particularly limited. The purification method used can be particularly selected from liquid / liquid extraction, distillation, crystallization, or a combination of these methods.

[0081] According to another embodiment of the present invention, the method according to the present invention may additionally comprise a step (c) of separating hydroquinone and catechol.

[0082] Thus, at the end of step (c), it is possible to obtain:

[0083] - in one aspect, a composition comprising at least 80% of hydroquinone and between 0.1 and 1000 ppm of at least one compound chosen from 2-(alkoxy)phenol, 4-(alkoxy)phenol, (alkyl)catechol and (alkyl)hydroquinone,

[0084] - and, in another aspect, a composition comprising at least 80% catechol and between 0.1 and 1000 ppm of at least one compound chosen from 2-(alkyl)phenol and 4-(alkyl)phenol.

[0085] Preferably, at the end of step (c), it is possible to obtain:

[0086] - in one aspect, a composition comprising at least 80% of hydroquinone and between 0.1 and 1000 ppm of at least one compound chosen from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, (tert-butyl)catechol and (tert-butyl)hydroquinone,

[0087] - and, in another aspect, a composition comprising at least 80% catechol and between 0.1 and 1000 ppm of at least one compound chosen from 2-(tert-butyl)phenol and 4-(tert-butyl)phenol.

[0088] Preferably, at the end of step (c), it is possible to obtain:

[0089] - in one aspect, a composition comprising at least 80% of hydroquinone and between 0.1 and 1000 ppm of at least one compound chosen from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, isopropylcatechol and isopropylhydroquinone,

[0090] - and, in another aspect, a composition comprising at least 80% of catechol and between 0.1 and 1000 ppm of at least one compound chosen from 2-isopropylphenol and 4-isopropylphenol.

[0091] Optionally, the method according to the present invention may comprise at least one step (d) of shaping the product obtained in step (c). The choice of method for shaping the product obtained at the end of step (c) is not limited. Therefore, the product obtained according to the method of the present invention may be crystalline or in the form of an amorphous powder. The product obtained according to the method of the present invention may be shaped into amorphous or crystalline flakes, beads, pellets or granules.

Claims

1. A composition comprising at least one compound selected from hydroquinone and catechol, characterized in that The composition additionally comprises between 0.1 and 10 000 ppm of at least one compound selected from 2-(alkoxy)phenol, 4-(alkoxy)phenol, 2-(alkyl)phenol, 4-(alkyl)phenol, (alkyl)catechol, (alkyl)hydroquinone and alkoxybenzene.

2. The composition of any one of claims 1 and 2, comprising at least 80% hydroquinone and between 0.1 and 1000 ppm of at least one compound selected from 2-(alkoxy)phenol, 4-(alkoxy)phenol, (alkyl)catechol and (alkyl)hydroquinone.

3. The composition of any one of claims 1 to 3, comprising at least 80% catechol and between 0.1 and 1000 ppm of at least one compound selected from 2-(alkyl)phenol and 4-(alkyl)phenol.

4. The composition according to claim 1, comprising at least one compound selected from the group consisting of hydroquinone and catechol, wherein The composition additionally comprises between 0.1 and 10,000 ppm of at least one compound selected from 2-(tert-butoxy)phenol, 4-(tert-butoxy)phenol, 2-(tert-butyl)phenol, 4-(tert-butyl)phenol, (tert-butyl)catechol, (tert-butyl)hydroquinone, and tert-butoxybenzene.

5. The composition according to claim 1, comprising at least one compound selected from the group consisting of hydroquinone and catechol, wherein The composition additionally comprises between 0.1 and 10 000 ppm of at least one compound selected from 2-(isopropoxy)phenol, 4-(isopropoxy)phenol, 2-isopropylphenol, 4-isopropylphenol, isopropylcatechol, isopropylhydroquinone and cumene.

6. A method for preparing a composition comprising at least one compound selected from hydroquinone and catechol, characterized in that The method comprises the step (a) of reacting phenol with hydrogen peroxide in the presence of a catalyst in a solvent.

7. The method according to claim 6, wherein The process additionally comprises at least one step (b) of purifying the composition obtained in step (a).

8. The method according to claim 7, wherein The process additionally comprises a step (c) of separating the hydroquinone and catechol, and optionally at least one step (d) of shaping the purified product obtained in step (c), the product obtained in step (d) possibly being crystalline or in the form of an amorphous powder.

9. The method according to any one of claims 6 to 8, characterized in that The catalyst is a heterogeneous catalyst, preferably a titanium-containing zeolite, preferably TS-1, TS-2, Ti-MWW or Ti-MCM68, more preferably TS-1.

10. The method according to any one of claims 6 to 9, characterized in that The solvent comprises an alcohol or a mixture of alcohols preferably selected from isopropanol, 2,2-dimethylpropanol and tert-butanol in the presence of a cosolvent selected from water and an alcohol selected from methanol, ethanol, isopropanol, n-propanol and n-butanol.

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