Patent Description:
Several methods for the O-dealkylation of aromatic compounds have been described. <CIT> for example discloses a process for the dealkylation of an arylalkylether, in particular the dealkylation of guaiacol to pyrocatechol. According to that process, the arylalkylether is heated in the presence of an aliphatic amine hydrohalide to a typical temperature of about <NUM>-<NUM>, while passing hydrohalic acid, for example HCI or HBr through the reaction mixture until the reaction is at least partially complete. Not only does the reaction make use of gaseous HCI, carciniogenic methyl chloride is produced as a side product of the demethylation reaction.

The action of BBr<NUM> as a reactant in the O-dealkylation of different arylmethyl ethers to provide phenols, has been disclosed first by <NPL>. This method however presents the disadvantage of a high cost and the use of a highly toxic reactant, which is corrosive and instable in air, inconvenient to handle and generates a large amount of toxic waste.

<NPL> disclose a method for the demethylation of various aromatic ethers by reaction with <NUM>-(diethylamino)ethanethiol. Although the <NUM>-(diethylamino)ethanethiol is a stable product and nontoxic, it is expensive and gives rise to the production of a stoichiometric amount of waste.

<CIT> discloses the use of γ-alumina, preferably carried on an acidic silica carrier as a catalyst in the demethylation or demethoxylation of aromatic compounds such as guaiacol. The catalyst may further include an oxide of Ag, Zr, Ni or Fe. The reaction may be carried out at a temperature of between <NUM> and <NUM> in the gas phase, in an inactive gas such as nitrogen or argon, or in the liquid phase for example using water as a solvent. However, besides demethylation also the demethoxylation is observed involving the formation of phenol. The high temperature renders the method impractical.

A few publications report on carbon dealkylation (C-dealkylation) of aromatic compounds, i.e. the removal of substituents bound through a C-atom of the aromatic ring.

<NPL> that eugenol can be transformed into guaiacol by removal of the C-substituent in a thermal reaction at <NUM>. Although the reaction requires the presence of a dedicated catalyst such as Pt/Al<NUM>O<NUM> or zeolite HY, guaiacol yields remain low.

The microbiologic method disclosed by <NPL> makes use of Paecilomyces variotii and Pestalotia palmarum microorganisms to convert ferulic acid into different compounds, and catechol and guaiacol were found in the mixture. The disadvantages of the method are the low yields achieved (about <NUM>% for catechol and <NUM>% for guaiacol) and difficulties to isolate these compounds which are contained in low concentration in a complex mixture, as well as the need to use special microorganisms.

The method disclosed by <NPL> gave <NUM>% catechol as a major product, in a reaction where eugenol is heated with PhNH<NUM>. HCl at <NUM>-<NUM> for <NUM>. This method however presents the disadvantages that use is made of a stoichiometric reagent which generates waste, namely N-methylaniline and N-methyl-<NUM>-propylaniline, further aniline and its derivatives are carcinogenic.

The method disclosed by Koželj and Petrič in Synlett <NUM> (<NUM>):<NUM>-<NUM> for the deacylation of methoxyphenyl alkyl ketones produces phenol but presents several disadvantages such as the need of using (very) large amounts of expensive reagents (triflic acid) and aromatic solvents, as well as it presents a very long processing time.

<NPL>) discloses a method for dealkylation of lignin and lignin model compounds using sulfuric acid under inert atmosphere. <CIT> discloses a method for preparing pyrocatechol from lignin in a two-step process with guaiacol as an intermediate product. <NPL>) disclosed a method for the synthesis of catechol from guaiacol. All of these references relate to O-dealkylation of compounds, and neither of them teaches or even suggests a method for the C-dealkylation of this type of compounds.

<NPL>) discloses methods for the decarboxylation and decarbonylation of compounds, and does not disclose methods for the dealkylation or deacylation of such compounds.

There is thus a need to a process for the defunctionalisation (i.e. deacylation and/or dealkylation) of aromatic compounds, which is simple and cost effective. The present invention therefore seeks to provide a simple and cost effective process for the defunctionalisation of aromatic compounds specially to produce phenol derivatives.

This objective is achieved using a method of the current invention, which is characterized by contacting the compound to be defunctionalized with an acid-containing aqueous reaction mixture using high temperature and high pressure conditions. <NPL>) discloses a method for conversion of guaiacol to catechol in high temperature water, no high pressure conditions have been disclosed or even suggested. Furthermore, Yang et al. , <NUM> does not disclose the C-dealkylation of compounds.

The present invention provides a method for the dealkylation and/or deacylation of a compound of formula (I)
<CHM>
wherein:.

In a particular embodiment of the method from the present invention, at least one of said R<NUM> moieties is in ortho- or para- position with respect to at least one of said R<NUM> moieties.

In another particular embodiment, said acid is a mineral acid selected from the list comprising: HCI, H<NUM>PO<NUM>, perchloric acid, chloric acid, HI, HBr, H<NUM>SO<NUM>, arene sulfonic acid, alkane sulfonic acid, nitric acid or a mixture of two or more of the afore-mentioned acids, or a Lewis acid such as a salt of Fe or Cu.

In yet a further embodiment, the reaction mixture of step c) contains at least <NUM> equivalents of acid, preferably at least <NUM> equivalents with respect to the compound of formula I.

In still a further embodiment, said inert gas is selected from the list comprising: N<NUM>, CO<NUM>, a noble gas, such as He, Ne, Ar, a gaseous alkane such as methane, or a mixture of two or more of the aforementioned gases.

In still a further embodiment, step c) is carried out at a temperature of at least <NUM>, specifically at least <NUM>, more specifically at least <NUM>; most specifically at least <NUM>.

In a further embodiment of the present invention, step c) is carried out at a pressure of at least <NUM> bar, specifically at least <NUM> bar, more specifically at least <NUM> bar.

Some very specific embodiments of the present invention can be any one of the following:.

In a second aspect, the application provides a method not according to the claimed invention for the dealkylation of a compound encompassing a moiety of formula (II)
<CHM>
wherein:
<CHM>
is absent or represents any carbon containing moiety;.

In a further embodiment of the second aspect (not according to the claimed invention), one or more of the following may apply:.

As already detailed herein above, the present invention provides a method for the dealkylation and/or deacylation of compounds.

Typical reaction products that may be produced by the process of this invention, depending on the nature of the starting product used include: phenol; <NUM>,<NUM> dihydroxybenzene (i.e. catechol); <NUM>,<NUM> dihydroxybenzene (i.e. resorcinol); <NUM>,<NUM> dihydroxybenzene (i.e. dihydroquinone); <NUM>,<NUM>,<NUM> trihydroxybenzene (i.e. pyrrogallol); <NUM>,<NUM>,<NUM> trihydroxybenzene; and combinations of any of these. The inventors have found that with the process of this invention, end product yields, typically of over <NUM>% may be obtained.

The process of the present invention presents the advantage of showing high yields and high selectivity towards desired end products in the removal of.

The main difference with the prior art known methods, in particular, resides in the possibility of C-dealkylation of the starting compounds, hence the ability for dealkylation and/or deacylation of compounds in which at least one of the side-chains is attached through a C atom.

Thereby, the process of this invention makes use of an acid (preferably a simple strong mineral acid), as the only reagent, without requiring the use of a reactive gas atmosphere such as H<NUM>. This is an advantage as the use of H<NUM> would also require the provision of stringent safety precautions in relation to flammability and explosion risk. The process of this invention presents the further advantage that the (mineral) acids do not give rise to the generation of undesired waste as a side product. Thus a low cost process is provided which does not require the use of expensive reagents or solvents, nor does it require the provision of a stringent reaction atmosphere or particular safety precautions.

More specifically, the application also provides a method not according to the claimed invention for the dealkylation and/or deacylation of compound encompassing a moiety of formula (X)
<CHM>
wherein:
<CHM>
represents the attachment point of the moiety of formula (X) to the remainder of the compound; preferably it is absent or represents any carbon containing moiety;.

More specifically, the present invention provides a method for the dealkylation and/or deacylation of a compound of formula (I)
<CHM>
wherein:.

In the context of the present invention, the term "dealkylation" is meant to be the removal of a carbon chain, optionally substituted with one or more substituents, and optionally containing one or more double or triple bonds.

In the context of the present invention, the term "deacylation" is meant to be the removal of a group containing a carbonyl moiety (i.e. C=O) bound via a carbon atom of the said carbonyl moiety to the compound; said carbon chain, optionally substituted with one or more substituents, and optionally containing one or more double or triple bonds.

When describing the compounds of the invention, the terms used are to be construed in accordance with the following definitions, unless a context dictates otherwise:
The term "alkyl" by itself or as part of another substituent refers to a linear, branched or cyclic hydrocarbon group; which may be saturated or contain one or more unsaturated bonds. Generally, alkyl groups of this invention comprise from <NUM> to <NUM> carbon atoms. When a subscript is used herein following a carbon atom, the subscript refers to the number of carbon atoms that the named group may contain. Thus, for example, C<NUM>-<NUM>alkyl means an alkyl of one to four carbon atoms. Examples of alkyl groups are methyl, ethyl, n-propyl, i-propyl, butyl, and its isomers (e.g. n-butyl, i-butyl and t-butyl); pentyl and its isomers, hexyl and its isomers, heptyl and its isomers, octyl and its isomers, nonyl and its isomers; decyl and its isomers. C<NUM>-C<NUM> alkyl includes all linear, branched, or cyclic alkyl groups with between <NUM> and <NUM> carbon atoms, and thus includes methyl, ethyl, n-propyl, i-propyl, butyl and its isomers (e.g. n-butyl, i-butyl and t-butyl); pentyl and its isomers, hexyl and its isomers, cyclopentyl, <NUM>-, <NUM>-, or <NUM>-methylcyclopentyl, cyclopentylmethylene, and cyclohexyl.

The term "optionally substituted alkyl" refers to an alkyl group optionally substituted with one or more substituents (for example <NUM> to <NUM> substituents, for example <NUM>, <NUM>, <NUM>, or <NUM> substituents or <NUM> to <NUM> substituents) at any available point of attachment. Non-limiting examples of such substituents include halo, hydroxyl, carbonyl, nitro, amino, oxime, imino, azido, hydrazino, cyano, aryl, heteroaryl, cycloalkyl, acyl, alkylamino, alkoxy, thiol, alkylthio, carboxylic acid, acylamino, alkyl esters, carbamate, thioamido, urea, sullfonamido and the like.

In the context of the present invention, the term "alkyl" is meant to include "alkenyl" and "alkynyl" groups which are straight-chain, cyclic, or branched-chain hydrocarbon radicals containing at least one carbon-carbon double or triple bond respectively.

The term "aromatic group" or "aryl" as used herein refers to a polyunsaturated, aromatic hydrocarbyl group having a single ring (i.e. phenyl) or multiple aromatic rings fused together (e.g. naphthalene or anthracene) or linked covalently, typically containing <NUM> to <NUM> atoms; wherein at least one ring is aromatic. The aromatic ring may optionally include one to three additional rings (either cycloalkyl, heterocyclyl, or heteroaryl) fused thereto. Aryl is also intended to include the partially hydrogenated derivatives of the carbocyclic systems enumerated herein. A non-limiting example of aryl or aromatic group is for example phenyl.

The aryl ring can optionally be substituted by one or more substituents. An "optionally substituted aryl" refers to an aryl having optionally one or more substituents (for example <NUM> to <NUM> substituents, for example <NUM>, <NUM>, <NUM> or <NUM>) at any available point of attachment. Non-limiting examples of such substituents are selected from halogen, hydroxyl, oxo, nitro, amino, hydrazine, aminocarbonyl, azido, cyano, alkyl, cycloalkyl, alkenyl, alkynyl, cycloalkylalkyl, alkylamino, alkoxy, -SO<NUM>-NH<NUM>, aryl, heteroaryl, aralkyl, haloalkyl, haloalkoxy, alkoxycarbonyl, alkylaminocarbonyl, heteroarylalkyl, alkylsulfonamide, heterocyclyl, alkylcarbonylaminoalkyl, aryloxy, alkylcarbonyl, acyl, arylcarbonyl, aminocarbonyl, alkylsulfoxide, -SO<NUM>Ra, alkylthio, carboxyl, and the like, wherein Ra is alkyl or cycloalkyl.

The term "carboxy" or "carboxyl" or "hydroxycarbonyl" by itself or as part of another substituent refers to the group -CO<NUM>H. Thus, a carboxyalkyl is an alkyl group as defined above having at least one substituent that is -CO<NUM>H.

The term "Amine" is defined as an -NH<NUM> moiety, in which one or two hydrogen atoms are optionally replaced by an alkyl chain.

In a specific embodiment, , the application provides a method not according to the claimed invention for dealkylation and/or deacylation of compound encompassing a moiety of formula (Xb)
<CHM>
wherein:.

In a further embodiment, the application provides a method not according to the claimed invention for the dealkylation (C-dealkylation) of a compound encompassing a moiety of formula (XI)
<CHM>
wherein:
<CHM>
represents the attachment point of the moiety of formula (XI) to the remainder of the compound; preferably it is absent or represents any carbon containing moiety;.

In a further embodiment, the present invention provides a method as defined herein, more specifically for the dealkylation (C-dealkylation) of a compound encompassing a moiety of formula (XIb)
<CHM>
wherein:.

In a further embodiment, , the application provides a method not according to the claimed invention for the deacylation of a compound encompassing a moiety of formula (XI)
<CHM>
wherein:
<CHM>
represents the attachment point of the moiety of formula (XI) to the remainder of the compound; preferably it is absent or represents any carbon containing moiety;.

In a further embodiment, the present invention provides a method as defined herein, more specifically for the deacylation of a compound encompassing a moiety of formula (XIb)
<CHM>
wherein:.

In a further embodiment, the application provides a method not according to the claimed invention for the dealkylation (O-dealkylation) of a compound encompassing a moiety of formula (XII)
<CHM>
wherein:
<CHM>
represents the attachment point of the moiety of formula (XII) to the remainder of the compound; preferably it is absent or represents any carbon containing moiety;.

In a further embodiment, the application provides a method not according to the claimed invention for the dealkylation (O-dealkylation) of a compound encompassing a moiety of formula (Xllb)
<CHM>
wherein:.

In yet a further embodiment and with respect to the C-dealkylation methods as defined herein, preferably, at least one of said R<NUM> moieties is in ortho- or para- position with respect to at least one of said R<NUM>.

In yet a further embodiment of the methods of the present invention; said acid having a pKa of maximum <NUM> is selected from the list comprising: HCI, H<NUM>PO<NUM>, perchloric acid, chloric acid, HI, HBr, H<NUM>SO<NUM>, arene sulfonic acid, alkane sulfonic acid, nitric acid or a mixture of two or more of the afore-mentioned acids. In another embodiment of the methods of the present application not encompassed by the wording of the claims; said acidic heterogenous catalyst is selected from the list comprising: an acidic zeolite or similar acidic heterogeneous catalyst. Preferred acids for use in the present invention are strong BrØnsted or Lewis acids with a pKa of maximum <NUM>, preferably maximum <NUM>, maximum <NUM>, maximum <NUM> or maximum <NUM>, more preferably maximum <NUM>, most preferably maximum -<NUM>, in particular maximum -<NUM>. Examples of acids suitable for use in the invention include mineral acids selected from the group of HCI (pKa = - <NUM>), perchloric acid (pKa about -<NUM>), chloric acid HCIO<NUM> (pKa = -<NUM>), HI (pKa = -<NUM>), HBr (pKa = -<NUM>), H<NUM>SO<NUM> (pKa1 = -<NUM>), arene sulfonic acid for example p-toluenesulfonic acid (pKa = -<NUM>), alkane sulfonic acid for example methanesulfonic acid (pKa = -<NUM>), nitric acid HNO<NUM> (pKa = - <NUM>), but also fluoroantimonic acid, FSO<NUM>HSbF<NUM>, carborane superacid, fluorosulfuric acid FSO<NUM>H (pKa = -<NUM>) and triflic acid CF<NUM>SO<NUM>H (pKa = -<NUM>). The use of weak acids, i.e. acids with a pKa above <NUM> or <NUM> usually results in conversion rates which are of low or no economic interest.

The amount of acid present in the reaction mixture is preferably at least <NUM> equivalents of acid, preferably at least <NUM> equivalents with respect to the reactant of formula I or II, (or alternatively Xlb), in particular at <NUM> concentration of the substrate, to ensure a sufficiently high conversion and yield of the desired end product.

The process of this invention is carried out in an atmosphere which is inert with respect to the substrate, any intermediates produced in the course of the process of this invention and any reactants used, in order to minimize the risk to reaction, degradation and/or oxidation of the reaction products or intermediates. Any gas which is inert with respect to the reactions taking place in the present invention may be suitably used. Particularly preferred inert gases are selected from the group of N<NUM>, CO<NUM>, a noble gas, in particular He, Ne, Ar, an alkane gas in particular methane, or a mixture of two or more of the afore-mentioned gases.

In order to achieve a sufficient conversion, the process of this invention is carried out at a temperature of at least <NUM>, preferably at least <NUM>, more preferably at least <NUM>, most preferably at least <NUM>, in particular at least <NUM>. Below a temperature of <NUM> conversion risks to be insufficient. Preferably the reaction is carried out at a temperature of about <NUM>, as this results in an optimum conversion - economic feasibility ratio.

The reaction is carried at a pressure of at least <NUM> bar, preferably at least <NUM> bar, more preferably at least <NUM> bar, most preferably about <NUM> bar. The elevated pressure has the effect that the risk to unwanted decomposition of the reactants and/or reaction products and boiling of the aqueous phase can be reduced to a minimum.

The process of this invention is preferably carried out in aqueous reaction mixture. The aqueous reaction mixture may exclusively comprise water as the solvent for the reaction, as this permits minimizing the risk to the occurrence of unwanted side reactions, and this is preferred. The solvent may however also contain one or more organic solvents conventionally used in the reaction of organic compounds, for example an alcohol, for example methanol, ethanol or butanol, dimethylcarbonate, DMSO, DMF or a mixture of two or more of the afore-mentioned solvents. The solvent is preferably selected such that it does not give rise to the formation of unwanted side products, or that it does not show any unwanted reaction with the reactants used. In case the aqueous reaction mixture contains an organic solvent, the volume proportion of the organic solvent will usually be not more than <NUM> vol. %, preferably not more than <NUM> or <NUM> vol. % with respect to the total volume of solvent used, to minimize the risk to the formation of unwanted byproducts caused by the reaction of the solvent with the reaction products or reactants.

When subjecting compounds of the invention as described above to the process of this invention, any substituents bound to the compound through a O moiety will be converted into an OH moiety (i.e. O-dealkylation) and any functional group bound to the compound through a C-C bond, for example an alkyl group (i.e. C-dealkylation) or an aldehyde group (i.e. deacylation) bound to the benzene ring, will be removed as well and be converted into a H moiety.

Compounds suitable for use within the methods of the invention may be obtained from the decomposition of biomass, in particular the decomposition of lignin. For example the lignin portion of biomass (in particular, wood) contains aromatic units which may be ideal precursors for phenols. Typical decomposition products include, without being limited hereto, molecules similar to:
<CHM>
<CHM>
<CHM>.

The major problem presented by biomass as a raw product is that the treatment of biomass (wood, lignin, agricultural waste etc.) typically produces aromatic derivatives with multiple additional substituents and mixtures of various aromatic derivatives which contain a wide variety of derivatives of phenol having a wide variety of substituents. The reaction product of lignin treatment is sometimes referred to as "lignin oil". In order to produce phenols from such complex mixtures, the compounds contained therein need to be subjected to a defunctionalization reaction - with the purpose of removing substituents from the complex molecule. This removal of substituents or functional groups will allow greatly simplifying the composition of the mixtures - and lignin oil or fractions thereof may be converted into mixtures of a few phenol derivatives only. The process of this invention therefore provides an economically feasible process for producing from a mixture of complex molecules, individual chemicals, or mixtures of a limited number of chemical compounds. Typical products contained in lignin pyrolysis oil include <NUM>-methylphenol, <NUM>-methylphenol, <NUM>-ethylphenol, <NUM>-propylphenol. With the process of this invention, this type of products may be converted into phenol, yielding over <NUM>% of the desired end product. Other decomposition products contained in lignin pyrolysis oil include guaiacol, which may be converted into catechol; <NUM>,<NUM>-dimethoxyphenol which may be converted into <NUM>,<NUM>,<NUM>-trihydroxybenzene.

Still further decomposition products contained in lignin pyrolysis oil include <NUM>,<NUM>,<NUM>-trimethoxybenzene, which may be converted into <NUM>,<NUM>,<NUM>-trihydroxybenzene.

Other applications may be related to the use of certain products available from biomass in abundant amounts via biotechnologic methods such as ferulic acid, coumaric acid, caffeic acid, vanillin, produced from the rice bran and other agricultural wastes. Further examples of compounds suitable for use in the process of this invention are disclosed in the examples below.

The present invention thus permits producing phenols from biomass. Phenols (compounds containing one or more OH group on a benzene ring - e.g. phenol, catechol, resorcinol, pyrogallol) are important chemicals for many applications (e.g. resins) and chemical intermediates for different products (e.g. catechol is the key intermediate for vanillin, important flavor). Currently, phenols are produced petrochemically. Methods for the production of phenols from biomass as provided by the present invention have not been developed to date, though it appears a promising approach and the interest for such production methods is in line with the society interest in "green" products, which originate from renewable feedstock.

In yet a further aspect, the present invention provides a method as defined herein; wherein the resulting end-product is catechol and said compound encompassing a moiety of formula (I) is selected from the list comprising: caffeic acid, ferulic acid, dihydroconiferyl alcohol, propylguaiacol, and <NUM>-(<NUM>,<NUM>-dimethoxyphenyl)propan-<NUM>-one.

In a specific embodiment, the present invention thus provides a method as defined herein; wherein the resulting end-product is phenol and said compound encompassing a moiety of formula (I) is selected from the list comprising: coumaric acid, tyrosine (L, D, or mixture of L/D isomers).

In another specific embodiment, the present invention provides a method as defined herein; wherein the resulting end-product is pyrogallol and said compound encompassing a moiety of formula (I) is selected from the list comprising: dihydrosinapyl alcohol, propylsyringol and <NUM>-(<NUM>,<NUM>,<NUM>-trimethoxyphenyl)propan-<NUM>-one.

In yet another embodiment, the present invention provides a method as defined herein; wherein the resulting end-product is phenol and said compound encompassing a moiety of formula (I) is selected from the list comprising: hydrogenated cardanol and hydrogenated cashew nut shell liquid.

In yet a further embodiment, the present invention provides a method as defined herein; wherein the resulting end-product is a mixture of catechol and pyrogallol and said compound encompassing a moiety of formula (I) is a mixture selected from the list comprising: dihydroconiferyl alcohol and dihydrosinapyl alcohol; propylguaiacol and propylsyringol; <NUM>-(<NUM>,<NUM>-dimethoxyphenyl)propan-<NUM>-one and <NUM>-(<NUM>,<NUM>,<NUM>-trimethoxyphenyl)propan-<NUM>-one.

As such, some very specific embodiments of the present invention can be any one of the following:.

As detailed herein, the method of the present invention includes an oxidation step where non-functionalized alkyl groups are present in the starting compounds, or alkylating step and oxidation step, where free -OH and non-functionalized alkyl groups are present in the starting compounds.

Hence, the method includes a functionalization step for saturated non-functionalized alkyl chains, such that they become suitable for deacylation using the methods of the present invention. With respect to this method, it is essential though that any free -OH groups are first alkylated, since otherwise, the functionalization step, i.e. oxidation step, does not work. For such alkylation and oxidation step, any suitable process could be used, however there are a few preferred methods for doing so, as detailed below (and in the examples part).

An exemplary suitable method for alkylation, preferably methylation of free OH groups within the present invention follows the following reaction scheme:
<CHM>.

The reactions are typically carried out at a temperature ranging from <NUM> to <NUM> for a minimum of <NUM>.

More specifically, suitable alkylation reagents, bases and solvents in the context of this method may be selected from the following lists:.

An exemplary suitable method for oxidizing the alkyl groups of R<NUM>, within the present invention follows the following reaction scheme:
<CHM>.

The reactions are typically carried out at a temperature of about <NUM> for a minimum of <NUM>. Suitable oxidants, additives and solvents in the context of this method may be selected from the following lists:.

As evident from the examples part, the use of an additive is optional, since the reaction also works without, however the yield is usually higher when a further additive is used.

Another exemplary suitable method for oxidizing the alkyl groups of R<NUM>, within the present invention follows the following reaction scheme:
<CHM>.

The reactions are typically carried out at a temperature of about <NUM> for a minimum of <NUM>. Suitable catalysts, oxidants, additives and solvents in the context of this method may be selected from the following lists:.

Yet another exemplary suitable method for oxidizing the alkyl groups of R<NUM>, within the present invention follows the following reaction scheme:
<CHM>.

Suitable catalysts, oxidant, and solvents in the context of this method may be selected from the following lists:.

The reactions are typically carried out at a temperature of a minimum of <NUM> for a minimum of <NUM>.

The application also provides a method not according to the claimed invention for the dealkylation of a compound encompassing a moiety of formula (II)
<CHM>
wherein:
<CHM>
is absent or represents any carbon containing moiety;.

In a further embodiment of the second aspect of the present application not according to the claimed invention, one or more of the following may apply:.

A <NUM> glass vial was charged with a magnetic stirring bar, the substrate for the experiment, the acid or alkaline reagent and <NUM> of the appropriate solvent or solvent mixture. The vial was closed properly with the correct cap and septum and the septum was pierced with a syringe needle. This vial was brought to the <NUM> Parr reactor and the reactor was closed properly. The reactor was flushed with the appropriate gas (<NUM> x <NUM> bar) and then filled with this gas (with the reported pressure). The reactor was heated to the reaction temperature and this temperature was maintained for the reported reaction time (it takes approx. <NUM> to reach <NUM>). After cooling down (from <NUM> to <NUM> in the air and from <NUM> to r. in an ice bath), the gas was released and the reactor was opened.

After opening the reactor, the crude reaction mixture was brought to a roundbottomed flask and the vial was rinsed with H<NUM>O (<NUM>). This aqueous reaction mixture was freezed by gently rotating the flask in liq. Subsequently, vacuum was applied until all volatiles were removed. If necessary, this freeze drying step was repeated multiple times. The residue was redissolved in acetone, filtered over a silica plug and the filtrate was concentrated under reduced pressure by using a rotary evaporator. The residue was analysed with NMR and MS (APCI) or LC-MS.

A <NUM> home made PTFE insert was charged with a magnetic stirring bar, the substrate for the experiment, the acid catalyst and <NUM> of the appropriate solvent or solvent mixture. This vial was left open and brought to the <NUM> Parr reactor and the reactor was closed properly. The reactor was flushed with N<NUM> gas (<NUM> x <NUM> bar) and then filled with N<NUM> gas (<NUM> bar). The reactor was heated to the reaction temperature and this temperature was maintained for the reported reaction time (it takes approx. <NUM> to reach <NUM>). After cooling down (from <NUM> to <NUM> in the air and from <NUM> to r. in an ice bath), the gas was released and the reactor was opened.

The reaction mixture was brought to a roundbottomed flask and the major part of the solvent was removed by using a rotary evaporator. Subsequently, the residue was freezed by gently rotating the flask in liq. N<NUM> and vacuum was applied until all volatiles were removed. If necessary, this freeze drying step was repeated multiple times. The residue was redissolved in acetone, filtered over a silica plug and the filtrate was concentrated under reduced pressure by using a rotary evaporator. The residue was analysed with NMR and MS (APCI) or LC-MS.

A <NUM> round bottomed flask was charged with a magnetic stirring bar, the substrate for the experiment, the alkylation reagent, the base and the solvent. Once reaction was completed, the reaction mixture was filtered and vacuum was applied until all volatiles were removed. The crude reaction mixture was brought to a <NUM> round bottomed flask and was further charged with a magnetic stirring bar, the oxidation reagents and the appropriate solvent or solvent mixture. Once reaction was completed, the reaction mixture was diluted with water, transferred to a separation funnel and extracted with an organic solvent. Vacuum was applied until all volatiles were removed.

A <NUM> glass vial was charged with a magnetic stirring bar, the previous crude mixture, the acid or alkaline reagent and <NUM> of the appropriate solvent or solvent mixture. The vial was closed properly with the correct cap and septum and the septum was pierced with a syringe needle. This vial was brought to the <NUM> Parr reactor and the reactor was closed properly. The reactor was flushed with the appropriate gas (<NUM> x <NUM> bar) and then filled with this gas (with the reported pressure). The reactor was heated to the reaction temperature and this temperature was maintained for the reported reaction time (it takes approx. <NUM> to reach <NUM>). After cooling down (from <NUM> to <NUM> in the air and from <NUM> to r. in an ice bath), the gas was released and the reactor was opened.

After opening the reactor, the crude reaction mixture was brought to a round bottomed flask and the vial was rinsed with H<NUM>O (<NUM>). This aqueous reaction mixture was freezed by gently rotating the flask in liq. Subsequently, vacuum was applied until all volatiles were removed. If necessary, this freeze drying step was repeated multiple times. The residue was redissolved in acetone, filtered over a silica plug and the filtrate was concentrated under reduced pressure by using a rotary evaporator. The residue was analysed with NMR and MS (APCI) or LC-MS.

This experiment was performed according to General procedure A. Eugenol (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% isolated yield (<NUM>, <NUM> mmol). <NUM>H NMR (<NUM>, CDCl<NUM>) δ <NUM>-<NUM> (m, <NUM>), <NUM>-<NUM> (m, <NUM>), <NUM> (s, <NUM>) ppm. <NUM>C NMR (<NUM>, CDCl<NUM>): δ <NUM> (C), <NUM> (CH), <NUM> (CH) ppm. HRMS (ESI) for C<NUM>H<NUM>O<NUM> [M+H]+ calcd. <NUM>, found <NUM>.

This experiment was performed according to General procedure A. Isoeugenol (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% isolated yield (<NUM>, <NUM> mmol).

This experiment was performed according to General procedure A. Ortho-eugenol (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. After cooling down, volatiles were not evaporated but mixed with DMSO-d<NUM> and a <NUM>H NMR spectrum was recorded with suppression of the H<NUM>O signal. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol) and MeOH in <NUM>% NMR Yield (<NUM> mmol).

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, <NUM>% aq. H<NUM>PO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, HOAc (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained, no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, H<NUM>BO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained, no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained, no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, <NUM> aq. HCl (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to a modified General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, FeCl<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Before the freeze drying step, NH<NUM>Cl (s) was added until saturation. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to a modified General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, FeBr<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Before the freeze drying step, NH<NUM>Cl (s) was added until saturation. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and a mixture of H<NUM>O (<NUM>) and ethanol (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), no starting material was recovered.

This experiment was performed according to General procedure A. Ferulic acid (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and a mixture of H<NUM>O (<NUM>) and ethanol (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained, no starting material was recovered.

This experiment was performed according to a modified General procedure A. Para-coumaric acid (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d6 and <NUM>H NMR was performed with suppression of the H<NUM>O signal. Phenol was obtained in <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to General procedure B. Dihydroconiferylalcohol (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% yield.

This experiment was performed according to General procedure A. <NUM>-(<NUM>-Hydroxypropyl)-<NUM>-methoxyphenol (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained (based on MS and NMR analysis).

This experiment was performed according to General procedure A. <NUM>-(<NUM>-Hydroxypropyl)-<NUM>-methoxyphenol (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% isolated yield (<NUM>, <NUM> mmol).

This experiment was performed according to a modified General procedure A. Dihydrosinapylalcohol (<NUM>, <NUM> mmol) was used as the substrate, FeCl<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Before the freeze drying step, NH<NUM>Cl (s) was added until saturation. Pyrogallol was obtained in <NUM>% NMR yield (<NUM> mmol). <NUM>H NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (bs, <NUM>), <NUM> (t, J = <NUM>, <NUM>), <NUM> (d, J = <NUM>, <NUM>) ppm. <NUM>C NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (C), <NUM> (C), <NUM> (CH), <NUM> (CH) ppm.

This experiment was performed according to General procedure A. Dihydrosinapylalcohol (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Pyrogallol was obtained in <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to a modified General procedure A. L-tyrosine (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM> and <NUM>H NMR was performed with suppression of the H<NUM>O signal. Phenol was obtained in <NUM>% NMR yield (<NUM> mmol), whereas the starting material remained for <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-dimethoxyphenyl)-<NUM>-(<NUM>-methoxyphenoxy)propane-<NUM>,<NUM>-diol (<NUM>, <NUM> mmol) was used as the substrate, <NUM> HCI (aq. , <NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield.

This experiment was performed according to a modified General procedure A. <NUM>-[(2R*,<NUM>*)-<NUM>-(<NUM>,<NUM>-dimethoxyphenyl)-<NUM>-(hydroxymethyl)-<NUM>-methoxy-<NUM>,<NUM>-dihydro-<NUM>-benzofuran-<NUM>-yl]propan-<NUM>-ol (<NUM>, <NUM> mmol) was used as the substrate, <NUM> HCI (aq. , <NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield.

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-[(2R*,<NUM>*)-<NUM>-(<NUM>,<NUM>-dimethoxyphenyl)-<NUM>-(hydroxymethyl)-<NUM>-methoxy-<NUM>,<NUM>-dihydro-<NUM>-benzofuran-<NUM>-yl]-propaan-<NUM>,<NUM>-diol (<NUM>, <NUM> mmol) was used as the substrate, <NUM> HCI (aq. , <NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield.

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-dimethoxyphenoxy)-<NUM>-[(<NUM>R*,<NUM>*)-<NUM>-(<NUM>,<NUM>-dimethoxyphenyl)-<NUM>-(hydroxymethyl)-<NUM>-methoxy-<NUM>,<NUM>-dihydro-<NUM>-benzofuran-<NUM>-yl]-propaan-<NUM>,<NUM>-diol (<NUM>, <NUM> mmol) was used as the substrate, <NUM> HCI (aq. , <NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield and pyrogallol was obtained in <NUM>% yield.

This experiment was performed according to a modified General procedure A. <NUM>,<NUM>'[(<NUM>,<NUM>aR*,<NUM>S*,6aR*)-tetrahydro-<NUM>,<NUM>-furo[<NUM>,<NUM>-c]furan-<NUM>,<NUM>-diyl]bis(<NUM>,<NUM>-dimethoxyphenol) (<NUM>, <NUM> mmol) was used as the substrate, <NUM> HCI (aq. , <NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Pyrogallol was obtained in <NUM>% yield.

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM> and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), Propanoic acid was obtained in <NUM>% NMR yield (<NUM> mmol) and methanol in <NUM>% (<NUM> mmol).

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM> and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), Propanoic acid was obtained in <NUM>% NMR yield (<NUM> mmol) and methanol in <NUM>% (<NUM> mmol).

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. MsOH (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM> and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol), Propanoic acid was obtained in <NUM>% NMR Yield (<NUM> mmol) and methanol in <NUM>% (<NUM> mmol).

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, oxalic acid (<NUM>, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM>and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. No catechol was obtained.

This experiment was performed according to General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) and methanol (<NUM>) as solvents. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained.

This experiment was performed according to General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) and acetonitrile (<NUM>) as solvents. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. No catechol was obtained.

This experiment was performed according to General procedure A. <NUM>-(<NUM>,<NUM>-Dimethoxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Only traces of catechol were obtained.

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>-Hydroxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM>and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. Phenol was obtained in <NUM>% NMR yield (<NUM> mmol), Propanoic acid was obtained in <NUM>% NMR yield (<NUM> mmol) and the substrate was recovered for <NUM>% (<NUM> mmol).

This experiment was performed according to a modified General procedure A. <NUM>-(<NUM>-Hydroxyphenyl)propan-<NUM>-one (<NUM>, <NUM> mmol) was used as the substrate, conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Instead of freeze drying the aqueous phase, the reaction mixture was mixed with DMSO-d<NUM>and <NUM>H NMR analysis was performed with suppression of the H<NUM>O signal. Phenol was obtained in <NUM>% NMR yield (<NUM> mmol), Propanoic acid was obtained in <NUM>% NMR Yyield (<NUM> mmol) and the substrate was recovered for <NUM>% (<NUM> mmol).

This experiment was performed according to General procedure A. Veratraldehyde (<NUM>, <NUM> mmol) was used as the substrate, conc. HCl (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% yield (based on NMR analysis).

This experiment was performed according to General procedure C. <NUM>-Methoxy-<NUM>-propylphenol (<NUM>, <NUM> mmol) was used as the substrate; dimethyl carbonate (<NUM>) as the alkylation reagent and the solvent, and Cs<NUM>CO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base for alkylation step; sodium persulfate (<NUM>, <NUM> mmol, <NUM> equiv. ) as the oxidation reagent, sodium acetate (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base and acetonitrile (<NUM>) and H<NUM>O (<NUM>) as the solvent mixture for oxidation step; conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent for C-dealkylation and O-dealkylation of side chains. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to General procedure C. <NUM>-Methoxy-<NUM>-propylphenol (<NUM>, <NUM> mmol) was used as the substrate; dimethyl carbonate (<NUM>) as the alkylation reagent and the solvent, and Cs<NUM>CO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base for alkylation step; sodium persulfate (<NUM>, <NUM> mmol, <NUM> equiv. ) as the oxidation reagent, sodium acetate (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base and acetonitrile (<NUM>) and H<NUM>O (<NUM>) as the solvent mixture for oxidation step; conc. H<NUM>SO<NUM> (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent for C-dealkylation and O-dealkylation of side chains. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. Catechol was obtained in <NUM>% NMR yield (<NUM> mmol).

This experiment was performed according to General procedure C. <NUM>-Methoxy-<NUM>-propylphenol (<NUM>, <NUM> mmol) was used as the substrate; dimethyl carbonate (<NUM>) as the alkylation reagent and the solvent, and Cs<NUM>CO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base for alkylation step; tBuOOH <NUM>% in H<NUM>O (<NUM>, <NUM> mmol, <NUM> equiv. ) as the oxidation reagent, FeCl<NUM>. <NUM><NUM>O (<NUM>, <NUM> mmol, <NUM> equiv. ) as the catalyst and pyridine (<NUM>) as the solvent for oxidation step; conc. HCl (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent for C-dealkylation and O-dealkylation of side chains. The reaction is performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure.

This experiment was performed according to General procedure C. <NUM>-Methoxy-<NUM>-propylphenol (<NUM>, <NUM> mmol) was used as the substrate; dimethyl carbonate (<NUM>) as the alkylation reagent and the solvent, and Cs<NUM>CO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base for alkylation step; O<NUM> (<NUM> bar) and N-hydroxyphthalimide (<NUM>, <NUM> mmol, <NUM> equiv. ) as the oxidation reagents, Co(OAc)<NUM>. <NUM><NUM>O (<NUM>, <NUM> mmol, <NUM> equiv. ) as the catalyst and BuOAc (<NUM>) as the solvent for oxidation step; conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent for C-dealkylation and O-dealkylation of side chains. The reaction is performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure.

This experiment was performed according to General procedure C. <NUM>-Methoxy-<NUM>-propylphenol (<NUM>, <NUM> mmol) was used as the substrate; dimethyl carbonate (<NUM>) as the alkylation reagent and the solvent, and Cs<NUM>CO<NUM> (<NUM>, <NUM> mmol, <NUM> equiv. ) as the base for alkylation step; <NUM>,<NUM>-dichloro-<NUM>,<NUM>-dicyano-<NUM>,<NUM>-benzoquinone (<NUM>, <NUM> mmol, <NUM> equiv. ) as the oxidation reagent, HCOOH (<NUM>, <NUM> mmol, <NUM> equiv. ) as the catalyst and dioxane (<NUM>) and H<NUM>O as the solvent mixture for oxidation step; conc. HCI (<NUM>µL, <NUM> mmol, <NUM> equiv. ) as acidic catalyst and H<NUM>O (<NUM>) as the solvent for C-dealkylation and O-dealkylation of side chains. The reaction is performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure.

This experiment was performed according to a modified General procedure A. <NUM>-Propylguaiacol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814E, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. <NUM>-Propylcatechol was obtained in <NUM>% yield. <NUM>H-NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (bs, <NUM>), <NUM> (d, J = <NUM>, <NUM>), <NUM> (d, J = <NUM>, <NUM>), <NUM> (dd, J = <NUM>, <NUM>, <NUM>), <NUM> (t, J = <NUM>, <NUM>), <NUM> (sextet, J = <NUM>, <NUM>), <NUM> (t, J = <NUM>, <NUM>) ppm. <NUM>C-NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (C), <NUM> (C), <NUM> (C), <NUM> (CH), <NUM> (CH), <NUM> (CH), <NUM> (CH<NUM>), <NUM> (CH<NUM>), <NUM> (CH<NUM>) ppm. HRMS (ESI) for C<NUM>H<NUM>O<NUM>[M+H]+ calcd. <NUM>, found <NUM>.

This experiment was performed according to a modified General procedure A. <NUM>-Propylguaiacol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. <NUM>-Propylcatechol was obtained in <NUM>% yield.

This experiment was performed according to a modified General procedure A. <NUM>-Propylguaiacol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. <NUM>-Propylcatechol was isolated in <NUM>% yield.

This experiment was performed according to a modified General procedure A. <NUM>-Propylsyringol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. <NUM>-Propylpyrogallol was obtained in <NUM>% yield and the mono-demethylated intermediate in <NUM>%.

This experiment was performed according to a modified General procedure A. <NUM>-Propylsyringol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using n-propanol, prior to freeze drying. <NUM>-Propylpyrogallol was obtained in <NUM>% yield and the mono-demethylated intermediate in <NUM>%.

This experiment was performed according to a modified General procedure A. Dihydroconiferylalcohol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814E, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. Dihydrocaffeylalcohol was obtained in <NUM>% yield. <NUM>H NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (bs, <NUM>), <NUM> (d, J = <NUM>, <NUM>), <NUM> (d, J = <NUM>, <NUM>), <NUM> (dd, J = <NUM>, <NUM>, <NUM>), <NUM> (bs, <NUM>), <NUM>-<NUM> (m, <NUM>), <NUM> (t, J = <NUM>, <NUM>), <NUM> (quintet, J = <NUM>, <NUM>) ppm. <NUM>C NMR (<NUM>, DMSO-d<NUM>): δ <NUM> (C), <NUM> (C), <NUM> (C), <NUM> (CH), <NUM> (CH), <NUM> (CH), <NUM> (CH<NUM>), <NUM> (CH<NUM>), <NUM> (CH<NUM>) ppm.

This experiment was performed according to a modified General procedure A. Dihydroconiferylalcohol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. Dihydrocaffeylalcohol was obtained in <NUM>% yield.

This experiment was performed according to a modified General procedure A. Dihydroconiferylalcohol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using acetone, prior to freeze drying. Dihydrocaffeylalcohol was obtained in <NUM>%.

This experiment was performed according to a modified General procedure A. Dihydroconiferylalcohol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using n-propanol, prior to freeze drying. Dihydrocaffeylalcohol was obtained in <NUM>% yield.

This experiment was performed according to a modified General procedure A. Dihydrosinapylalcohol (<NUM>, <NUM> mmol) was used as the substrate, zeolite beta (Zeolyst, CP814C, SiO<NUM>/Al<NUM>O<NUM> = <NUM>, H form) (<NUM>) as acidic catalyst and H<NUM>O (<NUM>) as the solvent. The reaction was performed at <NUM> for <NUM> under <NUM> bar of N<NUM> pressure. The zeolite was removed by filtration, using n-propanol, prior to freeze drying. <NUM>-(<NUM>-Hydroxypropyl)benzene-<NUM>,<NUM>,<NUM>-triol was obtained in <NUM>% yield and the mono-demethylated intermediate in <NUM>%.

As detailed already herein before, we herein also provide a method for preparing compounds suitable for use in the dealkylation and/or deacylation methods of the present invention. Such method is based on the functionalization (i.e. oxidation) of saturated non-funtionalized alkyl chains in the molecules. However, in order for the functionalization method to be carried out properly, first an alkylation (e.g. methylation) step of all free -OH groups need to be performed. While any suitable method for alkylation and oxidation may be used, we performed some several experiments to find suitable conditions for some particular methods as detailed below:.

a) Alkylation method - tested conditions:
<CHM>.

<CHM>
<CHM>
b) Oxidation method - tested conditions:
<CHM>.

Claim 1:
A method for the dealkylation and/or deacylation of a compound of formula (I)
<CHM>
wherein:
each occurrence of R<NUM> is independently selected to be -OH, or -O-alkyl; wherein alkyl refers to a linear, branched or cyclic hydrocarbon group which may be saturated or contain one or more unsaturated bonds;
each occurrence of R<NUM> is independently selected from an alkyl group which may be linear, branched or cyclic; which may be saturated or containing one or more unsaturated bonds, or which may be an aromatic group; wherein said R<NUM> may optionally further contain one or more heteroatoms and/or one or more substituents;
n is <NUM>-<NUM>;
m is <NUM>-<NUM>; and the sum of n and m is maximally <NUM>
said method comprising the steps of:
a) providing said compound of formula (I)
b) if in said compound of formula (I), said R<NUM> contains at least one alkyl group which does not have at least one functional moiety; then:
b1) alkylating any free -OH groups in said compound of step a); and
b2) oxidizing in said compound of step b1); said alkyl groups which do not have said at least one functional moiety;
wherein said at least one functional moiety is selected from the list consisting of: -OH, =O, a double bond or an amine;
c) preparing a reaction mixture by contacting said compound of step a), or where applicable step b), with an aqueous reaction mixture containing an acid having a pKa of maximum <NUM> or a Lewis acid, under an inert gas atmosphere;
wherein step c) is carried out at a temperature of at least <NUM> and a pressure of at least <NUM> bar;
d) obtaining from step c) a phenolic compound of formula (Ia)
<CHM>
wherein p is equal to n.