JP7210350B2 - Method for producing phosphonic acid derivative - Google Patents

Description

The present invention relates to a method for producing phosphonic acid derivatives. More particularly, the present invention relates to a method for producing a phosphonic acid derivative by reacting an ester group-containing phosphonic acid derivative in the presence of an acid catalyst.

Organophosphorus compounds are chemical substances that are widely used in various products such as flame retardants, plasticizers, insecticides, pharmaceuticals and agricultural chemicals, and ligands for metal complexes. In recent years, organophosphorus compounds have been attracting particular industrial attention as functional materials in the fields of constituent materials such as metal surface treatment agents and flame-retardant resins, and electronic materials.

Among organic phosphorus compounds, phosphonic acid derivatives are useful precursors of the various chemical substances described above, and thus various production methods have been investigated. For example, Non-Patent Document 1 proposes to hydrolyze an alkylphosphonic acid derivative in the presence of concentrated hydrochloric acid while refluxing.

Best Synthetic Methods Organophosphorus (V) Chemistry, Christopher M. Timperley, p146-147

However, in the production method described in Non-Patent Document 1, the reaction is carried out under reflux in the presence of corrosive concentrated hydrochloric acid, and strict management of reaction conditions is required. Moreover, in order to use it in the field of electronic materials that require high insulation properties, it is necessary to control the concentration of halogens and metals to a low concentration of ppm or ppb level. In the conventional production method as described in Non-Patent Document 1, most of the methods use hydrogen halide (hydrochloric acid, etc.) or metal catalysts (palladium, sodium hydroxide, etc.), so purification of the product is necessary. there were. Therefore, there has been no production method that can easily reduce the concentration of halogens and metals to low concentrations of ppm and ppb levels. In addition, toxic alkyl chlorides are produced as by-products.

Accordingly, an object of the present invention is to provide a method for producing a phosphonic acid derivative in which the reaction proceeds under relatively mild reaction conditions without using hydrogen halide or metal catalysts.

As a result of intensive studies to solve the above problems, the present inventors solved the above problems by reacting an ester group-containing phosphonic acid derivative in the presence of a super-strong acid catalyst in a solvent or without a solvent. I found that it can be done, and came to complete the present invention.

（式（１）中、Ｒ^１およびＲ^２は、それぞれ独立して、ヘテロ原子を含んでもよい置換もしくは非置換の炭化水素基であり、
ｎは１～３、ｍは０～２、ｏは０～１の自然数であり、ｎ＋ｍ＋ｏ＝３である）
で表されるホスホン酸誘導体の製造方法であって、
下記一般式（２）：

（式（２）中、Ｒ^３、Ｒ^４、およびＲ^５は、それぞれ独立して、ヘテロ原子を含んでもよい置換もしくは非置換の炭化水素基であり、
ｎは１～３、ｍは０～２、ｏは０～１の自然数であり、ｎ＋ｍ＋ｏ＝３である）
で表されるホスホン酸誘導体を、超強酸触媒の存在下、溶媒中もしくは無溶媒で反応させる工程を含む、ホスホン酸誘導体の製造方法。
［２］ 前記超強酸は、２５℃での酸解離定数が１００％硫酸よりも小さい酸である、［１］に記載の製造方法。
［３］ 前記超強酸が、トリフルオロメタンスルホン酸、フルオロスルホン酸、フルオロメタンスルホン酸、および末端にパーフルオロスルホン酸基を有するフッ素系樹脂からなる群から選択される少なくとも１種からなる群から選択される少なくとも１種である、［１］または［２］に記載の製造方法。
［４］ 式（１）中、Ｒ^１、およびＲ^２はそれぞれ独立して、アルキル基、アルケニル基、アリール基、アラルキル基、およびアルコキシ基からなる群から選択され、
式（２）中、Ｒ^３、Ｒ^４、およびＲ^５はそれぞれ独立して、アルキル基、アルケニル基、アリール基、およびアラルキル基からなる群から選択される、［１］～［３］のいずれかに記載の製造方法。
［５］ 式（１）中、Ｒ^１は、ビニル基またはフェニル基であり、Ｒ^２は、メトキシ基、エトキシ基、およびアリル基からなる群から選択され、
式（２）中、Ｒ^３は、ビニル基またはフェニル基であり、Ｒ^４は、メトキシ基、エトキシ基、およびアリル基からなる群から選択され、Ｒ^５は、イソプロピル基、ｔｅｒｔ－ブチル基、ベンジル基、メチルフェニルメチル基、およびアリル基からなる群から選択される、［１］～［４］のいずれかに記載の製造方法。
［６］ 前記溶媒が、有機溶媒である、［１］～［５］のいずれかに記載の製造方法。
［７］ 前記有機溶媒が、芳香族炭化水素である、［６］に記載の製造方法。
［８］ 前記芳香族炭化水素が、ベンゼンおよび／またはトルエンである、［７］に記載の製造方法。 That is, according to the present invention, the following inventions are provided.
[1] the following general formula (1):

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted hydrocarbon group that may contain a heteroatom,
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
A method for producing a phosphonic acid derivative represented by
The following general formula (2):

(in formula (2), R ³ , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group which may contain a heteroatom;
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
A method for producing a phosphonic acid derivative, comprising the step of reacting a phosphonic acid derivative represented by in the presence of a superacid catalyst in a solvent or in the absence of a solvent.
[2] The production method according to [1], wherein the superacid has an acid dissociation constant at 25°C lower than that of 100% sulfuric acid.
[3] The superacid is selected from the group consisting of at least one selected from the group consisting of trifluoromethanesulfonic acid, fluorosulfonic acid, fluoromethanesulfonic acid, and fluorine-based resins having perfluorosulfonic acid groups at their terminals. The production method according to [1] or [2], wherein at least one of the
[4] In formula (1), R ¹ and R ² are each independently selected from the group consisting of an alkyl group, an alkenyl group, an aryl group, an aralkyl group, and an alkoxy group;
In formula (2), R ³ , R ⁴ and R ⁵ are each independently selected from the group consisting of alkyl groups, alkenyl groups, aryl groups and aralkyl groups, any of [1] to [3] The manufacturing method according to
[5] in formula (1), R ¹ is a vinyl group or a phenyl group, R ² is selected from the group consisting of a methoxy group, an ethoxy group, and an allyl group;
In formula (2), R ³ is a vinyl group or a phenyl group, R ⁴ is selected from the group consisting of a methoxy group, an ethoxy group and an allyl group, R ⁵ is an isopropyl group, a tert-butyl group, The production method according to any one of [1] to [4], wherein the group is selected from the group consisting of a benzyl group, a methylphenylmethyl group and an allyl group.
[6] The production method according to any one of [1] to [5], wherein the solvent is an organic solvent.
[7] The production method according to [6], wherein the organic solvent is an aromatic hydrocarbon.
[8] The production method according to [7], wherein the aromatic hydrocarbon is benzene and/or toluene.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a method for producing a phosphonic acid derivative in which the reaction proceeds under relatively mild reaction conditions without using hydrogen halide or a metal catalyst.

[Method for producing phosphonic acid derivative]
The method for producing a phosphonic acid derivative of the present invention comprises a step of reacting an ester group-containing phosphonic acid derivative in the presence of a super-strong acid catalyst in a solvent or without a solvent.

（式（２）中、Ｒ^３、Ｒ^４、およびＲ^５は、それぞれ独立して、ヘテロ原子を含んでもよい置換もしくは非置換の炭化水素基であり、
ｎは１～３、ｍは０～２、ｏは０～１の自然数であり、ｎ＋ｍ＋ｏ＝３である）
で表されるエステル基含有ホスホン酸誘導体である。 [Reaction step]
(Ester group-containing phosphonic acid derivative)
The starting ester group-containing phosphonic acid derivative used in the reaction step has the following general formula (2):

(in formula (2), R ³ , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group which may contain a heteroatom;
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
is an ester group-containing phosphonic acid derivative represented by

In the reaction step of the present invention, the ester group (OR ⁵ ) of the starting phosphonic acid derivative is converted to a hydroxy group. When two or more ester groups (OR ⁵ ) are present, all of them may be converted to hydroxy groups, or only some of them may be selectively converted to hydroxy groups. Selective conversion of an ester group to a hydroxy group can be controlled by the structures of the leaving and remaining ester groups in R ⁵ of the ester group.

In the above formula (2), examples of hydrocarbon groups for R ³ , R ⁴ and R ⁵ include hydrocarbon groups having 1 to 10 carbon atoms. In addition, the number of carbon atoms of the substituent is not included in the above number of carbon atoms. Examples of hydrocarbon groups having 1 to 10 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group and hexyl group, Alkenyl groups such as vinyl group, 1-propenyl group, allyl group, 1-butenyl group, 2-butenyl group, 1,3-butadienyl group, pentenyl group, hexenyl group, phenyl group, tolyl group, xylyl group, naphthyl group, etc. aryl group, benzyl group, aralkyl group such as phenethyl group, and the like.

In the above formula (2), the substituents that the hydrocarbon groups of R ³ , R ⁴ and R ⁵ may have include, for example, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkyloxy group and a heterocyclic ring. groups, alkylidene groups, amino groups, silyl groups, acyl groups, acyloxy groups, carboxy groups, cyano groups, nitro groups, hydroxy groups, mercapto groups, oxo groups and the like. Examples of heterocyclic rings used as substituents include thienyl, pyrrolyl, furyl, pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, triazinyl, pyrrolidyl, piperidyl, quinolyl, and isoquinolyl groups. mentioned. Also, the number of carbon atoms contained in the substituent is preferably 1 to 12.

In formula (2) above, R ³ is preferably a vinyl group or a phenyl group.
In formula (2) above, R ⁴ is preferably a methoxy group, an ethoxy group, or an allyl group.
In formula (2) above, R ⁵ is preferably an isopropyl group, a tert-butyl group, a benzyl group, a methylphenylmethyl group, or an allyl group.

In the above formula (2), n is preferably a natural number of 1-2, m is a natural number of 1-2, and o is a natural number of 0-1.

上記式中、Ｐｈは、フェニル基を表し、Ｂｚｌは、ベンジル基を表し、^ｉＰｒは、イソプロピル基を表し、Ｍｅはメチル基を表し、Ｅｔはエチル基を表す。 Specific examples of the phosphonic acid derivative represented by the formula (2) include compounds represented by the following formula.

In the above formula, Ph represents a phenyl group, Bzl represents a benzyl group, ⁱ Pr represents an isopropyl group, Me represents a methyl group, and Et represents an ethyl group.

(acid catalyst)
A superacid is used as an acid catalyst in the reaction step. A superacid is an acid whose acid dissociation constant (pKa) at 25° C. is smaller than that of 100% sulfuric acid (pKa=−3.0). The acid dissociation constant (pKa) at 25° C. of the superacid used in the present invention is preferably −3.5 or less, more preferably −4.0 or less, and −5.0 or less. is more preferred.

The acid catalyst used in the reaction step may be a homogeneous catalyst or a heterogeneous catalyst. Homogeneous catalyst superacids include trifluoromethanesulfonic acid, fluorosulfonic acid, and fluoromethanesulfonic acid. In addition, examples of heterogeneous catalysts include fluorine-based resins having perfluorosulfonic acid groups at their terminals. Examples of such a perfluorocarbon material include a perfluorocarbon material having a hydrophobic Teflon skeleton and a perfluoro side chain having a sulfonic acid group (copolymer of tetrafluoroethylene and perfluoro[2-(fluorosulfonylethoxy)propyl vinyl ether ) or commercially available Nafion (registered trademark).

The amount of the superacid used in the reaction step is not particularly limited, but in consideration of reaction efficiency and reaction rate, it is preferably 0.01 to 10 molar equivalents, more preferably 0.01 to 10 molar equivalents, relative to 1 molar equivalent of the phosphonic acid derivative. It is 0.1 to 2.5 molar equivalents, more preferably 0.2 to 0.5 to 0.2 molar equivalents.

(solvent)
In the present invention, the reaction step may be carried out in a solvent or without a solvent. When a solvent is used, any organic solvent that exists in a liquid state under the reaction temperature conditions can be used. preferable.

Conventionally, the method for converting the ester group of a phosphonic acid derivative into a hydroxy group has involved a hydrolysis reaction using water as a solvent. Various problems have arisen, such as the need for a removal process. In the present invention, by carrying out the reaction in a non-aqueous system, the process can be simplified because there is no need to perform a step of removing water after the reaction. Furthermore, in the present invention, an aromatic hydrocarbon ( In the case of benzyl esters, the released by-products react with each other.) and can be converted to high-boiling components. Therefore, no combustible gas with a low boiling point is generated, and there is no need to treat gas components.

Examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene and the like. Among these, it is preferable to use benzene and toluene. By using benzene or toluene, by-products can be efficiently trapped. One of these organic solvents may be used alone, or two or more thereof may be used as a mixed solvent.

The amount of the solvent used in the reaction step is not particularly limited, and may be any amount suitable for the reaction operation and post-treatment. The amount of the solvent to be used is preferably about 0.1 to 10 times, more preferably about 1.0 to 5 times, the mass of the starting phosphonic acid derivative, on a mass basis.

(Reaction conditions)
The reaction temperature in the reaction step is not particularly limited, but is, for example, about 40° C. to 120° C., preferably 50° C. to 120° C., more preferably about 40° C. to 120° C. in consideration of reaction efficiency, reaction rate, and by-products. 60°C to 120°C.

The reaction time in the reaction step is not particularly limited, but is, for example, about 10 minutes to 48 hours, preferably 30 minutes to 36 hours, more preferably about 30 minutes to 36 hours, in consideration of reaction efficiency, reaction rate, and by-products. 1 hour to 24 hours.

The reaction step is preferably carried out under an inert gas atmosphere in consideration of reaction efficiency, reaction rate and by-products. Nitrogen, argon, or the like is preferably used as the inert gas.

（式（１）中、Ｒ^１およびＲ^２は、それぞれ独立して、ヘテロ原子を含んでもよい置換もしくは非置換の炭化水素基であり、
ｎは１～３、ｍは０～２、ｏは０～１の自然数であり、ｎ＋ｍ＋ｏ＝３である）
で表されるホスホン酸誘導体である。 (reaction product)
The product obtained in the above reaction step has the following general formula (1):

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted hydrocarbon group that may contain a heteroatom,
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
is a phosphonic acid derivative represented by

In formula (1) above, examples of the hydrocarbon groups for R ¹ and R ² include hydrocarbon groups having 1 to 10 carbon atoms. In addition, the number of carbon atoms of the substituent is not included in the above number of carbon atoms. Examples of hydrocarbon groups having 1 to 10 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group and hexyl group, Alkenyl groups such as vinyl group, 1-propenyl group, allyl group, 1-butenyl group, 2-butenyl group, 1,3-butadienyl group, pentenyl group, hexenyl group, phenyl group, tolyl group, xylyl group, naphthyl group, etc. aralkyl groups such as aryl groups, benzyl groups and phenethyl groups, and alkoxy groups such as methoxy groups and ethoxy groups.

In the above formula (1), the substituents that the hydrocarbon groups represented by R ¹ and R ² may have include, for example, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkyloxy group, a heterocyclic group, and an alkylidene group. , amino group, silyl group, acyl group, acyloxy group, carboxy group, cyano group, nitro group, hydroxy group, mercapto group, and oxo group. Examples of heterocyclic rings used as substituents include thienyl, pyrrolyl, furyl, pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, triazinyl, pyrrolidyl, piperidyl, quinolyl, and isoquinolyl groups. mentioned. Also, the number of carbon atoms contained in the substituent is preferably 1 to 12.

In formula (1) above, R ¹ is preferably a vinyl group or a phenyl group.
In formula (1) above, R ² is preferably a methoxy group, an ethoxy group, or an allyl group.

In the above formula (1), n is preferably a natural number of 1-2, m is a natural number of 1-2, and o is a natural number of 0-1.

上記式中、Ｐｈは、フェニル基を表し、Ｍｅはメチル基を表し、Ｅｔはエチル基を表す。 Specific examples of the phosphonic acid derivative represented by the above formula (1) include compounds represented by the following formula.

In the above formula, Ph represents a phenyl group, Me represents a methyl group, and Et represents an ethyl group.

(yield)
The yield of the phosphonic acid derivative obtained by the method for producing a phosphonic acid derivative of the present invention is preferably 60% or more, preferably 70% or more, on a molar basis with respect to the raw material ester group-containing phosphonic acid derivative. is more preferably 80% or more, and even more preferably 90% or more.

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[Example 1]
In a nitrogen atmosphere, 1.28 mmol of the ester group-containing phosphonic acid derivative described in Table 1 as the starting material and 1 mL of toluene were added to the reactor and stirred well. Then, 60 μL of trifluoromethanesulfonic acid (TfOH) was added and reacted at 100° C. for 24 hours to obtain the phosphonic acid derivative shown in Table 1 as the target substance. The yield of the obtained phosphonic acid derivative was 98% as measured by ³¹ P NMR. A by-product of the reaction reacted with toluene to produce methylallylbenzene (a mixture of ortho- and para-isomers).

[Example 2]
Phosphonic acid derivatives listed in Table 1 as target substances were obtained in the same manner as in Example 1, except that the acid catalyst was used in an amount of 30 µL and the reaction was carried out at 120°C. The yield of the obtained phosphonic acid derivative was 100% as measured by ³¹ P NMR. A by-product of the reaction reacted with toluene to produce methylallylbenzene (a mixture of ortho- and para-isomers).

[Example 3]
Phosphonic acid derivatives described in Table 1 as target substances were obtained in the same manner as in Example 2, except that benzene was used instead of toluene as the solvent. The yield of the obtained phosphonic acid derivative was 100% as measured by ³¹ P NMR. Incidentally, the by-product of the reaction reacted with benzene to produce allylbenzene.

[Example 4]
Phosphonic acid derivatives listed in Table 1 as target substances were obtained in the same manner as in Example 1, except that 15 μL of TfOH was used as an acid catalyst and the reaction was carried out at 120°C. The yield of the obtained phosphonic acid derivative was 88% as measured by ³¹ P NMR. A by-product of the reaction reacted with toluene to produce methylallylbenzene (a mixture of ortho- and para-isomers).

[Example 5]
Phosphonic acid derivatives listed in Table 1 as target substances were obtained in the same manner as in Example 1, except that 150 μL of TfOH was used as an acid catalyst and the reaction was carried out at 80° C. without adding a solvent. The yield of the obtained phosphonic acid derivative was 98% as measured by ³¹ P NMR.

[Example 6]
The target substance in Table 1 was obtained in the same manner as in Example 5 except that a fluororesin having a perfluorosulfonic acid group at the end represented by the following formula (solid catalyst, Nafion) represented by the following formula was used as the acid catalyst instead of TfOH. to obtain the phosphonic acid derivative described in . The yield of the obtained phosphonic acid derivative was 98% as measured by ³¹ P NMR.

[Comparative Example 1]
Phosphonic acid derivatives listed in Table 1 as target substances were obtained in the same manner as in Example 1, except that 15 μL of TfOH was used as the acid catalyst, water was used instead of toluene as the solvent, and the reaction was carried out at 140° C. for 38 hours. rice field. The yield of the obtained phosphonic acid derivative was 94% as measured by ³¹ P NMR. Since water was used as a solvent, high temperature and long reaction time were required.

[Comparative Example 2]
The reaction was carried out in the same manner as in Example 1, except that 1.0 mL of concentrated hydrochloric acid was used as the acid catalyst instead of TfOH and the reaction was carried out at 80° C., and the reaction proceeded quantitatively. As a by-product of the reaction, toxic chloromethane was produced.

A list of the above results is shown in Table 1.

[Example 7]
Under an argon atmosphere, 1 mmol of the ester group-containing phosphonic acid derivative described in the starting materials in Table 2 and 1 mL of benzene were added to a reaction vessel and stirred well. Then, 40 μL of TfOH was added and reacted at 80° C. for 24 hours to obtain the phosphonic acid derivatives listed in Table 2 as target substances. The yield of the obtained phosphonic acid derivative was 98% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce diphenylmethane.

[Example 8]
Using the ester group-containing phosphonic acid derivative described in the starting material in Table 2, the reaction was performed in the same manner as in Example 7 except that the reaction was performed at 40 ° C. to obtain the phosphonic acid derivative described in the target substance in Table 2. Obtained. The yield of the obtained phosphonic acid derivative was 90% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce 1,1-diphenylethane.

[Example 9]
The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out at 80° C. to obtain the phosphonic acid derivative described in Table 2 as the target substance. The yield of the obtained phosphonic acid derivative was 95% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce 1,1-diphenylethane.

[Example 10]
The reaction was carried out in the same manner as in Example 7 except that the ester group-containing phosphonic acid derivative described in Table 2 as the starting material was used to obtain the phosphonic acid derivative described in Table 2 as the target material. The yield of the obtained phosphonic acid derivative was 100% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce diphenylmethane.

[Example 11]
The reaction was carried out in the same manner as in Example 7 except that the ester group-containing phosphonic acid derivative described in Table 2 as the starting material was used to obtain the phosphonic acid derivative described in Table 2 as the target material. The yield of the obtained phosphonic acid derivative was 72% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce diphenylmethane.

[Comparative Example 3]
Using 680.0 g of the ester group-containing phosphonic acid derivative described in Table 2 as starting material, using 269.0 g of water instead of benzene as a solvent, and 54.0 g of vinylphosphonic acid as a catalyst, at 140° C. for 38 hours. The reaction was carried out to obtain the phosphonic acid derivative described in Table 2 as the desired substance. The yield of the obtained phosphonic acid derivative was 99% as measured by ³¹ P NMR. Since water was used as a solvent, high temperature and long reaction time were required. Methanol and dimethyl ether, which is a combustible gas, were produced as by-products of the reaction.

[Comparative Example 4]
Using 1 mmol of the ester group-containing phosphonic acid derivative described in Table 2 as the starting material, 1 mL of concentrated hydrochloric acid was reacted for 8 hours to obtain the phosphonic acid derivative described in Table 2 as the target material. The yield of the obtained phosphonic acid derivative was 97% as measured by ³¹ P NMR. As a by-product of the reaction, toxic chloroethane was produced.

A list of the above results is shown in Table 2.

[Example 12]
In a reaction vessel, 1 mmol of the ester group-containing phosphonic acid derivative described in Table 3 as the starting material and 1 mL of benzene were added and stirred well. Then, 20.2 μL of TfOH was added and reacted at 80° C. for 24 hours to obtain the phosphonic acid derivatives listed in Table 3 as target substances. The yield of the obtained phosphonic acid derivative was 93% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce diphenylmethane.

[Example 13]
The reaction was carried out in the same manner as in Example 12 except that the ester group-containing phosphonic acid derivative described in Table 3 as the starting material was used to obtain the phosphonic acid derivative described in Table 3 as the target material. The yield of the obtained phosphonic acid derivative was 80% as measured by ³¹ P NMR. A by-product of the reaction reacted with benzene to produce diphenylmethane.

A list of the above results is shown in Table 3. In Examples 12 and 13, only a portion of the ester groups of the starting phosphonic acid derivative could be selectively converted to hydroxy groups.

Claims (6)

The following general formula (1):

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted hydrocarbon group that may contain a heteroatom,
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
A method for producing a phosphonic acid derivative represented by
The following general formula (2):

(in formula (2), R ³ , R ⁴ and R ⁵ are each independently a substituted or unsubstituted hydrocarbon group which may contain a heteroatom;
n is 1 to 3, m is 0 to 2, o is a natural number of 0 to 1, and n + m + o = 3)
in the presence of an acid having an acid dissociation constant smaller than 100% sulfuric acid at 25°C as a super-strong acid catalyst, in an organic solvent or in the absence of a solvent. Method. 2. The superacid according to claim 1 , wherein the superacid is at least one selected from the group consisting of trifluoromethanesulfonic acid, fluorosulfonic acid, fluoromethanesulfonic acid, and fluorine-based resins having perfluorosulfonic acid groups at their ends. manufacturing method. wherein R ¹ and R ² are each independently selected from the group consisting of alkyl groups, alkenyl groups, aryl groups, aralkyl groups, and alkoxy groups;
^3. The preparation of claim 1 or 2 , wherein R3, ^R4 , and R5 in formula ( ² ) are each independently selected from the group consisting of alkyl groups, alkenyl groups, aryl groups, and aralkyl groups. Method. wherein R ¹ is a vinyl group or a phenyl group, R ² is selected from the group consisting of a methoxy group, an ethoxy group, and an allyl group;
In formula (2), R ³ is a vinyl group or a phenyl group, R ⁴ is selected from the group consisting of a methoxy group, an ethoxy group and an allyl group, R ⁵ is an isopropyl group, a tert-butyl group, 4. The production method according to any one of claims 1 to 3 , which is selected from the group consisting of a benzyl group, a methylphenylmethyl group and an allyl group. The production method according to any one of claims 1 to 4 , wherein the organic solvent is an aromatic hydrocarbon. 6. The production method according to claim 5 , wherein the aromatic hydrocarbon is benzene and/or toluene.