KR20220072544A - Method for preparing (meth)acrylic acid aryl ester - Google Patents

Abstract

The present invention relates to a method for producing (meth)acrylic acid aryl ester in a one-pot reaction through a process of producing a mixed anhydride through (meth)acrylic acid and carboxylic acid anhydride.

Description

(meth) acrylic acid aryl ester manufacturing method {METHOD FOR PREPARING (METH) ACRYLIC ACID ARYL ESTER}

The present invention relates to a method for preparing (meth)acrylic acid aryl esters. More specifically, it relates to a method for producing (meth)acrylic acid aryl ester through a process of producing a mixed anhydride using (meth)acrylic acid and carboxylic acid anhydride.

(meth)acrylic acid aryl esters can maintain the high refractive properties, low hygroscopicity, and heat resistance of aryl esters, so they are used in various fields such as plastics, paints, adhesives, paper processing agents, textile oils, lubricating oil additives, architectural sealants, inks, etc. and the field of application is expanding.

In general, esters are prepared by reacting carboxylic acid with alcohol, but it is known that the esterification reaction of (meth)acrylic acid with aryl alcohol does not proceed well. Accordingly, it is common to proceed with the ester reaction using an acid catalyst such as hydrochloric acid, but a large amount of by-products are generated compared to a low conversion rate, resulting in a low yield, and when a strong acid is used, problems such as deterioration of the final product are likely to occur.

In addition, a method of converting (meth)acrylic acid to (meth)acrylic acid anhydride and reacting with aromatic alcohol was studied. Therefore, research on each process of reacting (meth)acrylic acid with methacrylic acid anhydride and (meth)acrylic acid anhydride with a phenol-based compound has been conducted in the past, but the process is complicated in that a separate process must be performed. and incur additional costs.

Accordingly, in the esterification reaction of (meth)acrylic acid and aryl alcohol, there is a demand for improvement of selectivity and research on process simplification.

An object of the present specification is to provide a method for preparing (meth)acrylic acid aryl esters with high selectivity while the esterification reaction of (meth)acrylic acid and monovalent aryl alcohol is carried out in one vessel reaction.

The present invention comprises the steps of preparing a mixture by mixing (meth)acrylic acid, monovalent aryl alcohol, and a base (step 1); adding a compound represented by the following formula (1) to the mixture to produce a compound represented by the following formula (2) (step 2); An object of the present invention is to provide a method for preparing a (meth)acrylic acid aryl ester comprising a step (step 3) of reacting a compound represented by the following formula (2) with the monovalent aryl alcohol.

[Formula 1]

In Formula 1,

R ₁ and R ₂ are the same as or different from each other, and are each independently substituted or unsubstituted C _3-10 alkyl; or substituted or unsubstituted C _6-20 aryl;

[Formula 2]

In Formula 2,

R is R ₁ or R ₂ .

In addition, the terminology used herein is used only to describe exemplary embodiments, and is not intended to limit the present invention.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present specification, terms such as “comprise”, “comprising” or “have” are used to describe an embodied feature, number, step, component, or combination thereof, and include one or more other features, number, or step. , components, combinations or additions thereof are not excluded.

Since the present invention may have various changes and may have various forms, specific embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to the specific disclosed form, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

As used herein, “(meth)acrylic acid” is a generic term for acrylic acid and methacrylic acid.

"Monovalent aryl alcohol" refers to a compound in which one of the hydrogens of an aryl compound is substituted with -OH.

“(meth)acrylic acid aryl ester” is a generic term for an ester compound synthesized through an esterification reaction between (meth)acrylic acid, a type of carboxylic acid compound, and aryl alcohol.

"Mixed anhydride" refers to a compound represented by the above formula (2) produced by the reaction of (meth)acrylic acid and carboxylic acid anhydride.

"(meth)acrylic group" means an alkenyl group bonded to -COOH in (meth)acrylic acid.

“Target product” refers to (meth)acrylic acid aryl ester, and “by-product” refers to materials excluding unreacted substances, bases, and desired products from the mixture produced through step 3. For example, the “target product” may include (meth)acrylic acid phenyl ester, and the “by-product” may include phenyl acetate.

Hereinafter, the present invention will be described in detail.

The present invention comprises the steps of preparing a mixture by mixing (meth)acrylic acid, monovalent aryl alcohol, and a base (step 1); adding a compound represented by the following formula (1) to the mixture to produce a compound represented by the following formula (2) (step 2); Provided is a method for preparing (meth)acrylic acid aryl ester comprising a step (step 3) of reacting a compound represented by the following formula (2) with the monovalent aryl alcohol:

[Formula 1]

In Formula 1,

R ₁ and R ₂ are the same as or different from each other, and are each independently substituted or unsubstituted C _3-10 alkyl; Or a substituted or unsubstituted C _6-18 aryl,

[Formula 2]

In Formula 2,

R is R ₁ or R ₂ .

In the present invention, the substituents of the above formula will be described in more detail as follows.

C _3-10 alkyl may be straight chain, branched chain or cyclic alkyl. Specifically, the C _3-10 alkyl is C _3-10 straight chain alkyl; C _3-7 straight chain alkyl; C _3-5 straight chain alkyl; C _3-10 branched or cyclic alkyl; C _3-7 branched or cyclic alkyl; or C _3-5 branched or cyclic alkyl. More specifically, C _3-10 alkyl may be n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl or cyclopropyl, and the like.

C _6-20 aryl may be a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon. Specifically, C _6-20 aryl may be phenyl, naphthyl, or fluorenyl.

The method for preparing (meth)acrylic acid aryl ester of the present invention includes first mixing (meth)acrylic acid, monovalent aryl alcohol, and a base (step 1).

Monovalent aryl alcohol refers to a compound in which one of the hydrogens of aryl is substituted with -OH. Specific examples of the monovalent aryl alcohol include phenol, naphthol, or methoxyphenol, and may be used without particular limitation as long as the object of the present invention is not impaired. Preferably, the monovalent aryl alcohol may be phenol.

In the present invention, a base is used as a catalyst. The base catalyst serves to increase the reactivity between (meth)acrylic acid and the anhydride represented by Formula 1 to be added, thereby facilitating the production of a compound represented by Formula 2 to be described later. In addition, by undergoing the process of generating a compound represented by Formula 2 to be described later in the presence of a base, the formation of by-products can be suppressed. Accordingly, the present invention can increase the conversion rate of (meth)acrylic acid and suppress the generation of by-products, compared to the acid-catalyzed esterification reaction carried out under the existing acid catalyst.

The present invention includes the step of adding the compound represented by Formula 1 to the mixture of Step 1 to produce the compound represented by Formula 2 (Step 2).

The compound represented by Formula 1 corresponds to a kind of carboxylic acid anhydride. As an example, a carboxylic acid anhydride may be derived from a carboxylic acid and may be produced through the dehydration reaction of two carboxylic acids. As such, the compound represented by Formula 1 of the present invention derived from carboxylic acid includes an alkyl group or an aryl group at both ends, and includes a -(C=O)-O-(C=O)- structure.

The compound represented by the formula (1) reacts with (meth)acrylic acid to produce a compound represented by the formula (2). Specifically, the (meth)acrylic group of (meth)acrylic acid is exchanged with R ₁ or R ₂ of the compound represented by Formula 1 in the presence of a base. Through such an exchange reaction of the terminal substituents, a mixed anhydride represented by the formula (2) is produced.

Then, through the step (step 3) of the reaction of the compound represented by the formula (2) and the monovalent aryl alcohol, (meth) acrylic acid aryl ester is produced as a target product.

One terminal of the compound represented by Formula 2, that is, the mixed anhydride, includes R ₁ or R ₂ that does not react with (meth)acrylic acid, and the other terminal includes a (meth)acrylic group derived from (meth)acrylic acid. . The compound represented by Formula 2 is an intermediate product as described above, and has two carbonyl carbons, and the carbonyl carbon has high reactivity and can react with aryl alcohol. At this time, the aryl alcohol reacts with the carbonyl carbon bonded to R or with the carbonyl carbon bonded to the (meth)acrylic group. When reacting with the carbonyl carbon bonded to the (meth)acrylic group, the target product (meth) Acrylic acid aryl esters are formed, and when reacted with the carbonyl carbon bonded to R, a by-product is formed.

The present inventors show a difference in reactivity because the accessibility of aryl alcohol is different depending on the three-dimensional structure difference between the (meth)acrylic group and R group of the mixed anhydride in the reaction process of the mixed anhydride and the phenolic compound, and from this, the target product (meth) ) A substituent favorable to the production of acrylic acid aryl ester could be identified.

When the method for producing (meth)acrylic acid aryl ester according to the present invention as described above is schematically shown in Scheme 1 below.

[Scheme 1]

Preferably, in Formula 1, R ₁ and R ₂ may be the same as or different from each other, and may each independently be tert-butyl, or substituted or unsubstituted phenyl. As described above, the carbonyl carbon that reacts with the aryl alcohol varies due to the difference in the three-dimensional structure of R and the (meth)acrylic group. Accordingly, the accessibility of the aryl alcohol to the carbonyl carbon bonded to R must be low, the object of the present invention It is advantageous for the production of the product (meth)acrylic acid aryl ester.

In addition, according to one embodiment of the present invention, the molar ratio of the (meth)acrylic acid to the compound represented by Formula 1 may be 0.5:1 to 4:1. Preferably, the molar ratio of (meth)acrylic acid to the compound represented by Formula 1 may be 0.75:1 to 3:1, or 0.85:1 to 2:1. When the amount of (meth)acrylic acid is less than the above range, the mixed anhydride production is lowered and by-products may be increased. It may change or affect the purity.

Meanwhile, according to one embodiment of the present invention, the base may be a straight-chain, branched-chain, or cyclic compound containing nitrogen (N). Preferably, the base may include at least one selected from the group consisting of tetramethylethylenediamine, triethylamine, 1-methylimidazole, and dimethylaminopyridine.

In addition, according to one embodiment of the present invention, the molar ratio of the base to the compound represented by Formula 1 may be 0.1:1 to 0.99:1. Preferably, the molar ratio of the base: the compound represented by Formula 1 may be 0.15:1 to 0.95:1. If the amount of the base is less than the above range, there may be a problem in conversion, and if the amount of the base exceeds the above range, there may be a problem in selectivity, that is, the yield of the desired product.

According to one embodiment of the present invention, step 2 or step 3 may be performed at 30 °C to 80 °C. The esterification reaction of (meth)acrylic acid with aryl alcohol, including the process of producing a mixed anhydride according to the present invention, proceeds at a relatively low temperature compared to the existing acid catalyzed reaction, and as compared to the case where the reaction proceeds at a high temperature, If it is effective in suppression, there is little influence on the denaturation of the target product or the like. Preferably, step 2 or step 3 may be carried out at 35 °C to 70 °C, or 40 °C to 65 °C. When step 2 or step 3 is carried out at less than 30° C., the production rate of the mixed anhydride and the desired product is very slow, and when it proceeds above 80° C., the amount of by-products increases.

Furthermore, according to one embodiment of the present invention, there is provided a method for producing (meth)acrylic acid aryl ester satisfying the following formula (1).

[Equation 1]

n _T /n _S > 0.5

In Equation 1 above,

n _T means the number of moles of (meth)acrylic acid aryl ester,

n _S means the number of moles of by-products.

As described above, according to the method for producing (meth)acrylic acid aryl ester according to the present invention, the selectivity of the target product can be increased through the mixed anhydride production process, and the process is simple in that it proceeds as a one-pot reaction.

According to the method for preparing (meth)acrylic acid aryl ester of the present invention, (meth)acrylic acid aryl ester through a one-pot reaction of (meth)acrylic acid and monovalent aryl alcohol, even without separately preparing (meth)acrylic acid anhydride can increase the selectivity of

Hereinafter, through specific examples of the invention, the operation and effect of the invention will be described in more detail. However, these embodiments are merely presented as an example of the invention, and the scope of the invention is not defined thereby.

<Example>

Example 1-1

Methacrylic acid (MAA, 989 mg, 11.6 mmol) and phenol (1.09 g, 11.6 mmol) were mixed in a flask, tetramethylethylenediamine (TMEDA, 1.35 g, 11.6 mmol) was slowly added and stirred. Then, after adding pivalic anhydride (2.38 g, 12.7 mmol), the temperature was raised to 50 °C, and the reaction was carried out for 15 hours. Generation of the following mixed anhydride during the reaction was confirmed through NMR.

¹ H NMR: 6.17 (m, 1H), 5.79 (m, 1H), 1.98 (m, 3H), 1.29 (s, 9H)

Upon completion of the reaction, the mixture was diluted with 20 ml of hexane, filtered through a celite pad, and the filtrate was washed three times with 20 ml of 5% NaOH aqueous solution. Thereafter, the organic layer was dehydrated with MgSO ₄ (1 g) and concentrated to obtain a residue. The yield of methacrylic acid phenyl ester (PhMA) was confirmed through NMR of the obtained reisdue.

Example 1-2

A residue was obtained in the same manner as in Example 1-1, except that benzoic anhydride (2.89 g, 12.7 mmol) was used instead of pivalic anhydride.

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 2-1

PhMA was obtained in the same manner as in Example 1-1, except that MAA (2.00 g, 23.2 mmol) was used instead of MAA (989 mg, 11.6 mmol).

Example 2-2

A residue was obtained in the same manner as in Example 1-2, except that MAA (2.00 g, 23.2 mmol) was used instead of MAA (989 mg, 11.6 mmol).

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 3-1

PhMA was prepared in the same manner as in Example 2-1, except that TEA (1.17 g, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol).

Example 3-2

PhMA was obtained in the same manner as in Example 2-1, except that 1-methylimidazole (952 g, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol) and the reaction was carried out for 10 hours.

Example 3-3

PhMA was obtained in the same manner as in Example 2-1, except that dimethylaminopyridine (DMAP, 1.42 g, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol) and the reaction was carried out for 7 hours.

Example 3-4

A residue was obtained in the same manner as in Example 2-2, except that TEA (1.17 g, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol).

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 3-5

A residue was obtained in the same manner as in Example 2-2, except that 1-methylimidazole (952 mg, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol) and the reaction was carried out for 9 hours.

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 3-6

A residue was obtained in the same manner as in Example 2-2, except that DMAP (1.42 g, 11.6 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol) and the reaction was carried out for 9 hours.

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 4-1

PhMA was obtained in the same manner as in Example 2-1, except that TMEDA (674 mg, 5.80 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol).

Example 4-2

PhMA was obtained in the same manner as in Example 2-1, except that TMEDA (270 mg, 2.32 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol).

Example 4-3

A residue was obtained in the same manner as in Example 2-2, except that TMEDA (674 mg, 5.80 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol) and reacted for 21 hours.

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Example 4-4

A residue was obtained in the same manner as in Example 2-1, except that TMEDA (270 mg, 2.32 mmol) was used instead of TMEDA (1.35 g, 11.6 mmol), and reisdue was distilled under reduced pressure at 60 to 80 ° C. paid

Thereafter, the obtained residue was distilled under reduced pressure at 10 mbar or less at 60 to 80° C. to obtain PhMA.

Comparative Example 1-1

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 1-1, except that the reaction was carried out for 5 hours.

Comparative Example 1-2

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 2-1, except that the reaction was carried out for 5 hours.

Comparative Example 1-3

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 3-1, except that the reaction was carried out for 5 hours.

Comparative Example 1-4

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 3-2, except that the reaction was carried out for 3 hours.

Comparative Example 1-5

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 3-3, except that the reaction was carried out for 1 hour.

Comparative Example 1-6

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 4-1, except that the reaction was carried out for 3 hours.

Comparative Example 1-7

Acetic anhydride (1.30 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 4-2, except that the reaction was carried out for 3 hours.

Comparative Example 2

Phthalic anhydride (1.89 g, 12.7 mmol) was used instead of pivalic anhydride, and the experiment was carried out in the same manner as in Example 1-1, except that the reaction was carried out for 15 hours.

Comparative Example 3

MAA (1.10 g, 12.8 mmol), Phenol (1.00 g, 10.6 mmol) and Amberlyst 15 (100 mg) were added to the flask, and the temperature was raised to 100 °C, followed by reaction for 15 hours. After the reaction was completed, the mixture was diluted with hexane (20 ml), filtered through a celite pad, and the filtrate was washed three times with 20 ml of 5% NaOH aqueous solution. Thereafter, the organic layer was dehydrated with MgSO ₄ and concentrated to obtain a residue. The PhMA yield was confirmed through NMR of the obtained reisdue.

Comparative Example 4

MAA (4.12 g, 47.9 mmol), Phenol (3.00 g, 31.9 mmol), toluene (8 mL), and p-toluenesulfonic acid (p-TsOH, 607 mg, 3.19 mmol) were added to the flask, and the temperature was raised to 100° C. The reaction was carried out for 15 hours. After the reaction was completed, the mixture was diluted with hexane (20 ml), filtered through a celite pad, and the filtrate was washed 3 times with 20 ml of 5% NaOH aqueous solution. Thereafter, the organic layer was dehydrated with MgSO ₄ and concentrated to obtain a residue. The PhMA yield was confirmed through NMR of the obtained reisdue.

Comparative Example 5

In a flask, MAA (4.12 g, 47.9 mmol), Phenol (3.00 g, 31.9 mmol), xylene (6.8 g), H ₂ SO ₄ (78 mg, 0.80 mmol), and B(OH) ₃ (99 mg, 0.016 mmol) ) was added, and the temperature was raised to 150° C. to proceed with the reaction for 8 hours. After the reaction was completed, the mixture was diluted with hexane (20 ml), filtered through a celite pad, and the filtrate was washed 3 times with 20 ml of 5% NaOH aqueous solution. Thereafter, the organic layer was dehydrated with MgSO ₄ and concentrated to obtain a residue. The PhMA yield was confirmed through NMR of the obtained reisdue.

Comparative Example 6

MAA (4.12 g, 47.9 mmol), Phenol (3.00 g, 31.9 mmol), toluene (8 mL), and p-TsOH (607 mg, 3.19 mmol) were added to the flask, and the temperature was raised to 125° C. and the reaction was carried out for 20 hours. did After the reaction was completed, the mixture was diluted with hexane (20 ml), filtered through a celite pad, and the filtrate was washed three times with 20 ml of 5% NaOH aqueous solution. Thereafter, the organic layer was dehydrated with MgSO ₄ and concentrated to obtain a residue. The PhMA yield was confirmed through NMR of the obtained reisdue.

The types and amounts of main materials used in Examples and Comparative Examples are summarized in Table 1 below.

anhydride MAA usage catalyst catalyst amount reaction time Example 1-1 Pivalic anhydride 989 mg
(11.6 mmol) TMEDA 1.35 g
(11.6 mmol) 15 Example 1-2 Benzoic anhydride 989 mg
(11.6 mmol) TMEDA 1.35 g
(11.6 mmol) 15 Example 2-1 Pivalic anhydride 2.00 g
(23.2 mmol) TMEDA 1.35 g
(11.6 mmol) 15 Example 2-2 Benzoic anhydride 2.00 g
(23.2 mmol) TMEDA 1.35 g
(11.6 mmol) 15 Example 3-1 Pivalic anhydride 2.00 g
(23.2 mmol) TEA 1.17 g
(11.6 mmol) 15 Example 3-2 Pivalic anhydride 2.00 g
(23.2 mmol) 1-methylimidazole 952 g
(11.6 mmol) 10 Example 3-3 Pivalic anhydride 2.00 g
(23.2 mmol) DMAP 952 g
(11.6 mmol) 7 Example 3-4 Benzoic anhydride 2.00 g
(23.2 mmol) TEA 1.17 g
(11.6 mmol) 15 Example 3-5 Benzoic anhydride 2.00 g
(23.2 mmol) 1-methylimidazole 952 g
(11.6 mmol) 9 Example 3-6 Benzoic anhydride 2.00 g
(23.2 mmol) DMAP 952 g
(11.6 mmol) 9 Example 4-1 Pivalic anhydride 2.00 g
(23.2 mmol) TMEDA 674 mg
(5.80 mmol) 15 Example 4-2 Pivalic anhydride 2.00 g
(23.2 mmol) TMEDA 270 mg
(2.32 mmol) 15 Example 4-3 Benzoic anhydride 2.00 g
(23.2 mmol) TMEDA 674 mg
(5.80 mmol) 21 Example 4-4 Benzoic anhydride 2.00 g
(23.2 mmol) TMEDA 270 mg
(2.32 mmol) 21 Comparative Example 1-1 Acetic anhydride 989 mg
(11.6 mmol) TMEDA 1.35 g
(11.6 mmol) 5 Comparative Example 1-2 Acetic anhydride 2.00 g
(23.2 mmol) TMEDA 1.35 g
(11.6 mmol) 5 Comparative Example 1-3 Acetic anhydride 2.00 g
(23.2 mmol) TEA 1.17 g
(11.6 mmol) 5 Comparative Example 1-4 Acetic anhydride 2.00 g
(23.2 mmol) 1-methylimidazole 952 g
(11.6 mmol) 3 Comparative Example 1-5 Acetic anhydride 2.00 g
(23.2 mmol) DMAP 952 g
(11.6 mmol) One Comparative Example 1-6 Acetic anhydride 2.00 g
(23.2 mmol) TMEDA 674 mg
(5.80 mmol) 3 Comparative Example 1-7 Acetic anhydride 2.00 g
(23.2 mmol) TMEDA 270 mg
(2.32 mmol) 3 Comparative Example 2 Phthalic anhydride 989 mg
(11.6 mmol) TMEDA 1.35 g
(11.6 mmol) 15 Comparative Example 3 - 1.10 g
(12.8 mmol) Amberlyst 15 100 mg 15 Comparative Example 4 - 4.12 g
(4.79 mmol) p-TsOH 607 mg
(3.19 mmol) 15 Comparative Example 5 (xylene solvent) 4.12 g
(4.79 mmol) H ₂ SO ₄ , 78 mg
(0.80 mmol) 8 B(OH) ₃ 99 mg
(0.016 mmol) Comparative Example 6 (toluene solvent) 4.12 g
(4.79 mmol) p-TsOH 607 mg
(3.19 mmol) 20

<Experimental example>

(1) conversion of methacrylic acid, selectivity of methacrylic acid phenyl ester, and yield of methacrylic acid phenyl ester

1,3,5-methoxybenzene (standard material 1 g, 5.95 mmol) was added to the residue obtained in each Example and Comparative Example, stirred and then sampled 10 to 15 mg to measure NMR, and calculate the ratio with the standard material Thus, the conversion rate, selectivity and yield were calculated according to the following formula.

In the case of Comparative Example, it was calculated by comparing the amounts of PhMA produced without a standard substance and the remaining MAA, and the calculated conversion rate was assumed as the yield because there were no other by-products confirmed by NMR.

[Formula 1]

Conversion = {1 - (MAA CH ₃ peak * 3 /standard OMe peak ratio) * 5.95 / (MAA equivalent * 11.6)} * 100

[Formula 2]

Selectivity = PhMA CH ₃ peak / (RCOOPh peak R group * 3 / n)

where R = CH ₃ , n = 3; R = tert-Bu, n = 9.

[Formula 3]

Yield = (PhMA CH ₃ peak * 3 / standard OMe peak ratio) * 595 / 11.6

When vacuum distillation was performed, the yield was separately calculated by the amount of PhMA finally obtained compared to the amount of phenol added.

conversion rate selectivity
(PhMA/RCOOPh) transference number note Example 1-1 100% 1/1 46% Example 1-2 100% 4.9/1 75% vacuum distillation Example 2-1 100% 1.75/1 58% Example 2-2 100% 5.7/1 77% vacuum distillation Example 3-1 100% 1/1.5 36% Example 3-2 100% 1/2 30% Example 3-3 100% 1/1.8 33% Example 3-4 100% 2.2/1 63% vacuum distillation Example 3-5 100% 1.8/1 59% vacuum distillation Example 3-6 100% 3/1 68% vacuum distillation Example 4-1 100% 3/1 68% Example 4-2 100% 4.2/1 74% Example 4-3 100% 6.7/1 79% vacuum distillation Example 4-4 100% 7.5/1 80% vacuum distillation Comparative Example 1-1 100% 1/6 13% Comparative Example 1-2 100% 1/4.9 15% Examples 1-3 100% 1/8.1 8% Examples 1-4 100% - - Phenyl acetate 100% Examples 1-5 100% - - Phenyl acetate 100% Examples 1-6 100% - Phenyl acetate 100% Examples 1-7 100% - Phenyl acetate 100% Comparative Example 2 100% - - N.D. Comparative Example 3 10 - 10 Comparative Example 4 10 - 10 Comparative Example 5 20 - 20 Comparative Example 6 45 - 45

As can be seen from Table 1 above, when the method for producing the (meth)acrylic acid aryl ester of the present invention was used, the selectivity of the (meth)acrylic acid aryl ester as a target product was greatly improved. In addition, even under mild reaction conditions by using the base catalyst, a yield higher or similar to that of the acid catalyst could be obtained.

Claims (7)

preparing a mixture by mixing (meth)acrylic acid, monovalent aryl alcohol, and a base (step 1);
adding a compound represented by the following formula (1) to the mixture to produce a compound represented by the following formula (2) (step 2);
Comprising the step (step 3) of reacting the compound represented by the formula (2) and the monovalent aryl alcohol,
Method for preparing (meth)acrylic acid aryl ester:
[Formula 1]

In Formula 1,
R ₁ and R ₂ are the same as or different from each other, and are each independently substituted or unsubstituted C _3-10 alkyl; or substituted or unsubstituted C _6-20 aryl;
[Formula 2]

In Formula 2,
R is R ₁ or R ₂ .
The method of claim 1,
In Formula 1, R ₁ and R ₂ are the same as or different from each other, and are each independently tert-butyl, or substituted or unsubstituted phenyl;
A method for producing (meth)acrylic acid aryl ester.
The method of claim 1,
The (meth)acrylic acid: the molar ratio of the compound represented by Formula 1 is 0.5:1 to 4:1,
A method for producing (meth)acrylic acid aryl ester.
The method of claim 1,
The base comprises at least one selected from the group consisting of tetramethylethylenediamine, triethyleneamine, 1-methylimidazole, and dimethylaminopyridine,
A method for producing (meth)acrylic acid aryl ester.
According to claim 1,
The base: the molar ratio of the compound represented by Formula 1 is 0.1:1 to 0.99:1,
A method for producing (meth)acrylic acid aryl ester.
According to claim 1,
The step 2 or step 3 is carried out at 30 ℃ to 80 ℃,
A method for producing (meth)acrylic acid aryl ester.
According to claim 1,
Satisfying Equation 1 below,
Method for preparing (meth)acrylic acid aryl ester:
[Equation 1]
n _T /n _S > 0.5
In Equation 1 above,
n _T means the number of moles of (meth)acrylic acid aryl ester,
n _S means the number of moles of by-products.