KR20200043649A - Method for preparing methylene diphenyl-4,4'-dicarbamate derivative by condensation reaction of urethane - Google Patents

Abstract

The present invention relates to a method for manufacturing a methylene diphenyl-4,4′-dicarbamate derivative which comprises a step of manufacturing the methylene diphenyl-4,4′-dicarbamate derivative by conducting a condensation reaction of a N-phenyl carbamate derivative and formaldehyde by using clay carrying heteropoly acid as a catalyst. By the same, it is possible to manufacture the methylene diphenyl-4,4′-dicarbamate derivative which is eco-friendly by not using a toxic reactant, and has a high yield.

Description

METHOD FOR PREPARING METHYLENE DIPHENYL-4,4'-DICARBAMATE DERIVATIVE BY CONDENSATION REACTION OF URETHANE}

The present invention relates to a method for producing a methylene diphenyl-4,4'-dicarbamate derivative, and more specifically, by condensation reaction of an N-phenylcarbamate derivative with formaldehyde using a clay carrying a heteropoly acid as a catalyst. It relates to a method for preparing a methylene diphenyl-4,4'-dicarbamate derivative.

Methylene diphenyl-4,4'-dicarbamate derivative is an important precursor for preparing methylene diphenyl diisocyanate (MDI), which is a key monomer for synthesizing polyurethane, and various manufacturing methods capable of producing it are studied have.

The existing method for preparing methylene diphenyl diisocyanate uses phosgene, which is not only environmentally friendly by using phosgene, which is highly toxic and corrosive, but also has a disadvantage that corrosive hydrochloride is produced as a by-product. Accordingly, a method for producing methylene diphenyl diisocyanate without using phosgene has been developed for the purpose of eliminating these disadvantages.

One of them is the condensation reaction of methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO), and methylene diphenyl-4,4'-dicarbamate , MDC). So far, liquid acid catalysts such as H ₂ SO ₄ , HCl, H ₃ PO ₄ and CF ₃ SO ₃ H have given the best catalytic activity in the condensation reaction, but there is a problem that the corrosion of the equipment is high. To avoid the disadvantages of such liquid acid catalysts, the use of solid catalysts such as ZnCl ₂ , SbCl ₅ and heteropoly acids is contemplated, but environmentally unfriendly such as nitrobenzene, toluene, 2-heptanone, diether and mixed solvents. It is necessary to use a phosphorus organic solvent, and there is a problem that it is difficult to recover and separate the solvent after the reaction.

Recently, zeolite H _β is used as a catalyst, and a reaction is performed in the presence of dimethyl carbonate (DMC) as a solvent and a methylene diphenyl-4,4′-dicarbamate synthesis raw material to yield methylene diphenyl- in a yield of 76%. Although a method for producing 4,4'-dicarbamate has been disclosed, high temperature is required as an optimized reaction condition, and the regenerated catalyst has a problem that it must be fired at a very high temperature before reuse.

Therefore, there is a need for a process capable of producing methylene diphenyl-4,4'-dicarbamate in an environmentally friendly manner by using high catalyst performance and recyclable catalyst under mild reaction conditions.

An object of the present invention is to produce an methylene diphenyl-4,4'-dicarbamate derivative in an environmentally friendly manner under mild reaction conditions by condensation reaction using N-phenylcarbamate derivative and formaldehyde as a catalyst carrying heteropoly acid as a catalyst. It is to provide a method for producing a methylene diphenyl-4,4'-dicarbamate derivative.

Another object of the present invention is to provide a catalyst for preparing methylene diphenyl-4,4'-dicarbamate derivatives having high catalyst performance and being recyclable.

According to an aspect of the present invention, methylene diphenyl represented by Structural Formula 2 by condensation reaction using N-phenylcarbamate derivative represented by Structural Formula 1 below and clay containing heteropoly acid as a catalyst as a catalyst A method for preparing a methylene diphenyl-4,4'-dicarbamate derivative is provided, comprising the step of preparing a -4,4'-dicarbamate derivative.

[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,

R ¹ are each independently a C1 to C3 alkylene group,

R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group.

In addition, R ¹ may be a methylene group and R ² may be a hydrogen atom.

Further, R ¹ may be an ethylene group, and R ² may be a methoxy group.

Further, R ¹ may be an ethylene group, and R ² may be a hydroxy group.

In addition, the heteropoly acid is phosphotungstic acid (Phosphotungstic acid, H ₃ PW ₁₂ O ₄₀ ), phosphomolybdic acid (Phosphomolybdic acid, H ₃ PMo ₁₂ O ₄₀ ), phosphomolybdenum tungstic acid (Phosphomolybdotungstic acid, H ₃ PW _x Mo _{12 - x} O ₄₀ (0 <x <12)) and silicon tungstic acid (Silicotungstic acid, H ₄ [W ₁₂ SiO ₄₀ ]).

In addition, the heteropoly acid may include phosphotungstic acid (H ₃ PW ₁₂ O ₄₀ ).

In addition, the clay is at least one selected from montmorillonite, pyrophyllite, talc, nontronite, bititerite, saponite, kaolinite, dickite, nacrite, metahaloysite, halosite, and muscobyte It may include.

In addition, the clay may include montmorillonite.

In addition, the clay on which the heteropoly acid is supported may include montmorillonite on which phosphotungstic acid is supported.

In addition, the condensation reaction may be performed as a solution reaction using a solvent.

In addition, the solvent may include one or more selected from dimethyl carbonate, diethyl carbonate and bis (2-methoxyethyl) carbonate (BMEC: bis (2-methoxyethyl) carbonate).

In addition, the molar ratio of the formaldehyde and the N-phenyl carbamate derivative may be 1: 2 to 1: 6.

In addition, the catalyst may be 30 to 150 parts by weight based on 100 parts by weight of the N-phenylcarbamate derivative.

In addition, the solvent may be 2,000 to 6,000 parts by weight based on 100 parts by weight of the N-phenylcarbamate derivative.

In addition, the reaction may be carried out at a temperature of 50 to 200 ℃.

In addition, the reaction may be performed for 1 to 10 hours.

In addition, the method for preparing a methylene diphenyl-4,4'-dicarbamate derivative comprises (a ') mixing a mixture of heteropoly acid, clay and water, and stirring to prepare a mixture containing a heteropoly acid-supported clay; And (b ') preparing the clay carrying the heteropoly acid by washing and drying the clay carrying the heteropoly acid of the mixture with a pH of 7.

According to another aspect of the present invention, for preparing a methylene diphenyl-4,4'-dicarbamate derivative represented by Structural Formula 2 by condensation reaction of an N-phenyl carbamate derivative represented by Structural Formula 1 and formaldehyde below A heteropolyacid-supported clay for use as a catalyst is provided.

[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,

R ¹ are each independently a C1 to C3 alkylene group,

R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group.

The method for producing the methylene diphenyl-4,4'-dicarbamate derivative of the present invention has a high catalyst performance and uses a recyclable clay containing a heteropoly acid as a catalyst to obtain a high yield of methylene diphenyl-4,4'- Dicarbamate derivatives can be prepared.

In addition, methylene diphenyl-4,4'-dicarbamate derivatives can be prepared in an environmentally friendly manner by not using toxic reactants under mild reaction conditions.

Since these drawings are for reference to explain exemplary embodiments of the present invention, the technical spirit of the present invention should not be construed as being limited to the accompanying drawings.
1 shows an X-ray diffraction (XRD) pattern of montmorillonite (K30-TPA), montmorillonite K30, and tungstophosphoric acid (TPA) modified with tungstophosphoric acid prepared according to Preparation Example 1.
Figure 2 shows an infrared spectrometer (Infrared Spectrometer, IR) spectrum of a methylene diphenyl-4,4'-dicarbamate derivative.
Figure 3 shows the nuclear magnetic resonance (Nuclear magnetic resonance, ¹ H NMR) spectrum of the methylene diphenyl-4,4'- dicarbamate derivative.
FIG. 4 is a schematic diagram showing conversion rates of N-phenylcarbamate derivatives of Example 1 and Comparative Examples 1 to 3 and yields of methylene diphenyl-4,4'-dicarbamate derivatives.
5 is a diagram showing the conversion of the N-phenyl carbamate derivatives of Examples 1 to 4 and the yield of methylene diphenyl-4,4'-dicarbamate derivatives.
6 is a diagram showing the conversion of the N-phenyl carbamate derivatives of Examples 4 to 8 and the yield of methylene diphenyl-4,4'-dicarbamate derivatives.
7 is a diagram showing the conversion of the N-phenyl carbamate derivatives of Examples 7 and 9 to 11 and the yield of methylene diphenyl-4,4'-dicarbamate derivatives.
FIG. 8 is a schematic diagram showing conversion rates of N-phenylcarbamate derivatives of Examples 12 to 15 and yields of methylene diphenyl-4,4'-dicarbamate derivatives.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice.

However, the following description is not intended to limit the present invention to specific embodiments, and when it is determined that a detailed description of known technologies related to the present invention may obscure the subject matter of the present invention, the detailed description will be omitted. .

The terms used herein are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, terms such as “include” or “have” are intended to indicate that a feature, number, step, operation, component, or combination thereof described in the specification exists, or that one or more other features or It should be understood that numbers, steps, operations, elements, or combinations thereof do not preclude the presence or addition possibilities of those in combination.

Further, terms including ordinal numbers such as first and second to be used below may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may be referred to as a first component.

Also, when a component is said to be "formed" or "stacked" on another component, it may be formed or stacked directly attached to the front or one side of the surface of the other component, but may be intermediate. It should be understood that other components may exist in the.

Hereinafter, a method for preparing a methylene diphenyl-4,4'-dicarbamate derivative using the N-phenylcarbamate derivative and formaldehyde of the present invention will be described in detail. However, this is presented as an example, and the present invention is not limited thereby, and the present invention is only defined by the scope of claims to be described later.

The method for preparing the methylene diphenyl-4,4'-dicarbamate derivative of the present invention is a condensation reaction using N-phenylcarbamate derivative represented by the following structural formula 1 and formaldehyde-supported clay with heteropoly acid as a catalyst. reaction) to prepare a methylene diphenyl-4,4'-dicarbamate derivative represented by the following structural formula 2.

[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,

R ¹ are each independently a C1 to C3 alkylene group,

R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group.

In addition, R ¹ may be a methylene group and R ² may be a hydrogen atom.

Further, R ¹ may be an ethylene group, and R ² may be a methoxy group.

Further, R ¹ may be an ethylene group, and R ² may be a hydroxy group.

In addition, the heteropolyacid is phosphotungstic acid (phosphotungstic acid, H ₃ PW ₁₂ O ₄₀ ), phosphomolybdic acid (H ₃ PMo ₁₂ O ₄₀ ), phosphomolybdenum tungstic acid (Phosphomolybdotungstic Acid, H ₃ PW _x Mo _{12 - x} O ₄₀ (0 <x <12)) and silicon tungstic acid (Silicotungstic acid, H ₄ [W ₁₂ SiO ₄₀ ]) It may include at least one selected from, preferably phosphotungstic acid ( phosphotungstic acid, H ₃ PW ₁₂ O ₄₀ ).

In addition, the clay is at least one selected from montmorillonite, pyrophyllite, talc, nontronite, bititerite, saponite, kaolinite, dickite, nacrite, metahaloysite, halosite, and muscobyte It may include, and preferably may include montmorillonite.

In addition, the clay on which the heteropoly acid is supported may include montmorillonite on which phosphotungstic acid is supported.

In addition, the condensation reaction may be performed as a solution reaction using a solvent.

Further, the solvent may include one or more selected from dimethyl carbonate, diethyl carbonate and bis (2-methoxyethyl) carbonate (BMEC: Bis (2-methoxyethyl) carbonate), and preferably includes dimethyl carbonate can do.

In addition, the molar ratio of the formaldehyde and the N-phenylcarbamate derivative may be 1: 2 to 1: 6, and preferably 1: 3 to 1: 5.

In addition, the catalyst may be 30 to 150 parts by weight with respect to 100 parts by weight of the N-phenyl carbamate derivative, preferably 50 to 120 parts by weight, more preferably 70 to 100 parts by weight.

In addition, the solvent may be 2,000 to 6,000 parts by weight based on 100 parts by weight of the N-phenyl carbamate derivative, preferably 2,500 to 4,500 parts by weight, and more preferably 2,800 to 3,500 parts by weight.

In addition, the reaction may be carried out at a temperature of 50 to 200 ℃, preferably 80 to 170 ℃, more preferably 100 to 150 ℃. When the reaction temperature of the reaction is less than 50 ° C, the rate of the condensation reaction of the N-phenylcarbamate derivative and formaldehyde is slow, which is undesirable, and when it exceeds 200 ° C, a side reaction occurs and the catalyst is decomposed at a high temperature to methylene diphenyl- It is difficult to prepare 4,4'-dicarbamate derivatives, which is not preferable.

In addition, the reaction can be carried out for 1 to 10 hours, preferably 2 to 9 hours, more preferably 3 to 8 hours. When the reaction time of the reaction is less than 1 hour, the condensation reaction of the N-phenylcarbamate derivative and formaldehyde does not proceed well, and if it exceeds 10 hours, by-products are increased, which is undesirable.

In addition, the method for preparing a methylene diphenyl-4,4'-dicarbamate derivative comprises (a ') mixing a mixture of heteropoly acid, clay and water, and stirring to prepare a mixture containing a heteropoly acid-supported clay; And (b ') preparing the clay carrying the heteropoly acid by washing and drying the clay carrying the heteropoly acid of the mixture with a pH of 7.

To prepare a methylene diphenyl-4,4'-dicarbamate derivative represented by Structural Formula 2 by condensation reaction of N-phenyl carbamate derivative represented by Structural Formula 1 and formaldehyde below with the heteropoly acid-supported clay of the present invention It is intended to be used as a catalyst.

[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,

R ¹ are each independently a C1 to C3 alkylene group,

R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group.

When the clay on which the heteropoly acid is supported is used as a catalyst for preparing a methylene diphenyl-4,4'-dicarbamate derivative, it is possible to provide a process that saves energy, cost, and time without using a toxic reactant.

Therefore, the methylene diphenyl-4,4'-dicarbamate derivative can be prepared in high yield by condensation reaction of N-phenylcarbamate derivative and formaldehyde by the clay on which the heteropoly acid is supported.

[Example]

Hereinafter, a preferred embodiment of the present invention will be described. However, this is for illustrative purposes, and the scope of the present invention is not limited thereby.

Manufacturing example  One

Preparation of a montmorillonite catalyst carrying phosphotungstic acid (H ₃ PW ₁₂ O ₄₀ ) was performed by an initial wetness impregnation.

2 g of Montmorillonite K30 is dried in an oven at 110 ° C. for 12 hours. Then, 5 mL of distilled water solvent containing 1 g of phosphotungstic acid was added to the dried montmorillonite and stirred at room temperature for 24 hours.

Thereafter, the product was washed with water and ethanol until the pH value was 7, and dried in an oven at 90 ° C. for 12 hours to prepare a montmorillonite (K30-TPA) catalyst carrying phosphotungstic acid.

Example  One

Methylene diphenyl-4,4'-dicarbamate (MDC) was synthesized in a Teflon-lined stainless autoclave.

Methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) in a molar ratio of 4: 1 methyl N-phenylcarbamate 1.1 g (7.3 mmol), formalin (37 wt% formaldehyde) And water) 0.13 mL (1.8 mmol) was added to the autoclave, and 0.6 g of catalyst prepared according to Preparation Example 1 and 30 mL of dimethyl carbonate (DMC) were also added to the autoclave. Thereafter, the reaction mixture was heated to 160 ° C., then vigorously stirred for 4 hours using a magnetic bar, and the catalyst was separated to prepare methylene diphenyl-4,4′-dicarbamate.

Example  2

Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that the reaction temperature was performed at 140 ° C instead of 160 ° C.

Example  3

Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that the reaction temperature was performed at 120 ° C instead of 160 ° C.

Example  4

Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that the reaction temperature was performed at 90 ° C instead of 160 ° C.

Example  5

Methylene diphenyl-4 in the same manner as in Example 1, except that the reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 1 hour instead of 3 hours. 4'-dicarbamate was prepared.

Example  6

Methylene diphenyl-4 in the same manner as in Example 1, except that the reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 2 hours instead of 3 hours. 4'-dicarbamate was prepared.

Example  7

Methylene diphenyl-4 in the same manner as in Example 1, except that the reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 4 hours instead of 3 hours. 4'-dicarbamate was prepared.

Example  8

Methylene diphenyl-4 in the same manner as in Example 1, except that the reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 8 hours instead of 3 hours. 4'-dicarbamate was prepared.

Example  9

The reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 4 hours instead of 3 hours, and the molar ratio of methyl N-phenylcarbamate and formaldehyde was 4: 1. Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that it was carried out in 2: 1 instead of being carried out in.

Example  10

The reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 4 hours instead of 3 hours, and the molar ratio of methyl N-phenylcarbamate and formaldehyde was 4: 1. Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that it was carried out in 3: 1 instead of being carried out in.

Example  11

The reaction temperature was performed at 90 ° C. instead of 160 ° C., and the reaction time was performed at 4 hours instead of 3 hours, and the molar ratio of methyl N-phenylcarbamate and formaldehyde was 4: 1. Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that it was performed with 6: 1 instead of with.

Example  12

Methylene diphenyl-4,4'-dicarbamate was prepared in the same manner as in Example 1, except that the reaction time was performed for 4 hours instead of 3 hours.

Example  13

Methylene diphenyl-4,4'-dicarba in the same manner as in Example 1, except that the reaction time was performed for 4 hours instead of 3 hours, and 0.8 g was used instead of 0.6 g of catalyst. Mates were prepared.

Example  14

Methylene diphenyl-4,4'-dicarba in the same manner as in Example 1, except that the reaction time was performed for 4 hours instead of 3 hours, and 1.0 g of catalyst was used instead of 0.6 g. Mates were prepared.

Example  14

Methylene diphenyl-4,4'-dicarba in the same manner as in Example 1, except that the reaction time was performed for 4 hours instead of 3 hours, and 1.2 g of catalyst was used instead of 0.6 g. Mates were prepared.

Comparative example  One

Methylene diphenyl-4,4 in the same manner as in Example 1, except that montmorillonite K10 was used as a catalyst instead of montmorillonite (K30-TPA) carrying phosphotungsten acid prepared according to Preparation Example 1 as a catalyst. '-Dicarbamate was prepared.

Comparative example  2

Methylene diphenyl-4,4 in the same manner as in Example 1, except that montmorillonite K30 as a catalyst was used instead of montmorillonite (K30-TPA) carrying phosphotungsten acid prepared according to Preparation Example 1 as a catalyst. '-Dicarbamate was prepared.

Comparative example  3

Methylene diphenyl-4 in the same manner as in Example 1, except that phosphotungstic acid-supported montmorillonite (K30-TPA) prepared according to Preparation Example 1 was used as a catalyst instead of phosphotungstic acid as a catalyst. , 4'-dicarbamate was prepared.

Table 1 below summarizes the reaction conditions of methylene diphenyl-4,4'-dicarbamate production according to Examples 1 to 15 and Comparative Examples 1 to 3.

division catalyst MPC: HCHO
Mole ratio Catalyst usage
(g) Reaction temperature
(℃) Reaction time
(hr) Example 1 K30-TPA 4: 1 0.6 160 3 Example 2 K30-TPA 4: 1 0.6 140 3 Example 3 K30-TPA 4: 1 0.6 120 3 Example 4 K30-TPA 4: 1 0.6 90 3 Example 5 K30-TPA 4: 1 0.6 90 One Example 6 K30-TPA 4: 1 0.6 90 2 Example 7 K30-TPA 4: 1 0.6 90 4 Example 8 K30-TPA 4: 1 0.6 90 8 Example 9 K30-TPA 2: 1 0.6 90 4 Example 10 K30-TPA 3: 1 0.6 90 4 Example 11 K30-TPA 6: 1 0.6 90 4 Example 12 K30-TPA 4: 1 0.6 160 4 Example 13 K30-TPA 4: 1 0.8 160 4 Example 14 K30-TPA 4: 1 1.0 160 4 Example 15 K30-TPA 4: 1 1.2 160 4 Comparative Example 1 K10 4: 1 0.6 160 3 Comparative Example 2 K30 4: 1 0.6 160 3 Comparative Example 3 TPA 4: 1 0.6 160 3

[Test Example]

Test example  One: Phosphotungsten acid Supported  Montmorillonite (K30-TPA) catalyst analysis

1 shows an X-ray diffraction (XRD) pattern of montmorillonite (K30-TPA), montmorillonite K30, and tungstophosphoric acid (TPA) carrying phosphotungstic acid prepared according to Preparation Example 1. It was analyzed in the range of 10 to 80 ° using a Bruker D505 powder diffractometer with CuKα radiation.

According to Figure 1, when comparing the XRD spectrum of montmorillonite K30 and montmorillonite (K30-TPA) carrying phosphotungstic acid, the same diffraction line exists, but the peak of montmorillonite carrying phosphotungstic acid It can be seen that the strength is lower than montmorillonite K30. It can be seen that the crystallinity of montmorillonite was reduced as phosphotungsten acid was supported on montmorillonite.

Test example  2: methylene diphenyl-4,4'- Dicarbamate  analysis

FIG. 2 shows an infrared spectrometer (IR) spectrum of methylene diphenyl-4,4'-dicarbamate, and FIG. 3 shows nuclear magnetic resonance (Nuclear) of methylene diphenyl-4,4'-dicarbamate magnetic resonance, ¹ H NMR).

According to Fig 2, showing a second 2990cm ^-1 1703cm point, 1238cm ^-1 points, methyl and methylene new peak representing the new peak of the COC bond that represents the new peak of 3332cm ^-1 point, a carbonyl group represents a new peak amine ^-1 , 2940cm ^-1, 2917cm ^-1, and 2848 ^cm-1 point, 1322cm showing a new peak of 1604cm ^-1, coupled 1529cm ^-1, 1510cm ^-1 and 1409cm ^-1 points, and CN represents the new peak of a skeleton of benzene ring ^{- It} can be seen that peaks exist at points ¹ and 1073 cm ^-1 .

According to FIG. 3, analysis was performed using a nuclear magnetic resonance device (Bruker advance nuclear magnetic resonance spectroscopy ( ¹ H NMR), 500 MHz), dimethyl sulfoxide (DMSO) was used as a solvent, and ¹ H NMR spectrum ( 500 MHz, DMSO): δ 3.63 (s, 6H, OCH3), 3.74 (s, 2H, CH2), 7.07 (m, 4H, ArH), 7.31 (m, 4H, ArH), 9.52 (s, 2H, CH2) Appeared.

Therefore, according to FIGS. 2 and 3, the structure of methylene diphenyl-4,4'-dicarbamate can be confirmed.

Test example  3: methylene diphenyl-4,4'- Dicarbamate  Conversion rate and yield analysis

150mm, 5μm) 칼럼, 유속 0.3ml/min 및 254nm의 UV-detector)를 사용하여 분석하였으며, CH₃OH/H₂O (75/25)를 이동상으로 사용하였다. The filtrates obtained by separating the catalysts in Examples 1 to 15 and Comparative Examples 1 to 3 were analyzed by high performance liquid chromatography (HPLC). High performance liquid chromatography (HPLC) equipment (Agilent Technologies 1200 series, Allure C-18 (4.6mm)

150 mm, 5 μm) column, flow rate of 0.3 ml / min and UV-detector of 254 nm) were used, and CH ₃ OH / H ₂ O (75/25) was used as the mobile phase.

The yield of methylene diphenyl-4,4'-dicarbamate and the conversion rate of methyl N-phenylcarbamate were calculated based on the following equations 1 and 2.

[Equation 1]

[Equation 2]

Effect of catalyst

4 and Table 2 show the results of a study on the effect of the catalyst on the preparation of methylene diphenyl-4,4'-dicarbamate.

division catalyst MPC conversion rate
(%) MDC yield
(%) Example 1 K30-TPA 71.2 70.9 Comparative Example 1 K10 80.6 50.5 Comparative Example 2 K30 81.2 55.6 Comparative Example 3 TPA 55.7 44.2

According to FIG. 4 and Table 2, Comparative Example 2 using K30 as a catalyst was 55.6%, and yield slightly higher than 50.5% of Comparative Example 1 using K10 as a catalyst. This shows that K30 has a relatively high activity because it has a Bronsted acidity of 330 m ² g ^-1 greater than the surface area of K10 greater than 250 m ² g ^-1 . In addition, phosphotungstic acid itself having a Bronsted acidity shows methylene diphenyl-4,4'-dicarbamate yield 44.2% at 55.7% conversion of methyl N-phenylcarbamate, so methylene diphenyl-4,4 '-The activity of phosphotungstic acid can be confirmed in the dicarbamate production process.

Therefore, Example 1 using phosphotungstic acid-supported montmorillonite (K30-TPA) as a catalyst had a high conversion rate of methyl N-phenylcarbamate of 71.2% and methylene diphenyl-4,4'-dicarbamate yield of 70.9%. It can be confirmed that it exhibits performance.

Influence of reaction temperature, thermal stability and recyclability

5 and Table 3 show the results of the study on the effect of temperature on methylene diphenyl-4,4'-dicarbamate production.

division reaction
Temperature
(℃) Primary Secondary 3rd MPC
Conversion rate
(%) MDC yield
(%) MPC
Conversion rate
(%) MDC yield
(%) MPC
Conversion rate
(%) MDC yield
(%) Example 1 160 71.2 70.9 20.5 5.4 15.5 4.8 Example 2 140 83.9 65.2 15.2 4.8 10.0 4.0 Example 3 120 71.4 61.3 89.0 60.5 75.5 60.0 Example 4 90 80 62.1 82.6 61.6 80.0 60.5

According to FIG. 5, it can be seen that when the temperature reached 160 ° C, the yield of methylene diphenyl-4,4'-dicarbamate gradually increased to 70.9%.

Table 3 shows the conversion rate of methyl N-phenylcarbamate and methylene diphenyl-4,4'-dica when montmorillonite (K30-TPA) catalyst loaded with phosphotungstic acid was reused for testing the thermal stability and recyclability of the catalyst. It shows the yield of Lebamate. The catalyst was dried in an oven at 50 ° C. for 12 hours after each reaction and then reused.

According to Table 3, when the catalyst reacted at a temperature higher than 120 ° C is reused, it can be seen that both the conversion rate of methyl N-phenylcarbamate and the yield of methylene diphenyl-4,4'-dicarbamate decrease. Therefore, it can be seen that when the reaction temperature exceeds 120 ° C, the catalyst is decomposed and deactivated in the condensation reaction.

Therefore, the optimized reaction temperature for the condensation reaction appears to be 90 ° C.

Effect of reaction time

6 and Table 4 show the results of the study on the effect of reaction time on methylene diphenyl-4,4'-dicarbamate production.

division Reaction time
(hr) MPC conversion rate
(%) MDC yield
(%) Example 4 3 80 62.1 Example 5 One 75.1 58.9 Example 6 2 81.6 61.8 Example 7 4 86.2 71.5 Example 8 8 88 64

According to FIG. 6 and Table 4, the yield and the conversion rate were slowly increased at a reaction time of 1 to 4 hours, but it was confirmed that the decrease was slightly at 8 hours. Therefore, it appears that the appropriate reaction time of the condensation reaction is 4 hours.

methyl  N- Phenylcarbamate ( MPC ) And formaldehyde ( HCHO ) Molar ratio influence

7 and Table 5 show the results of a study on the effect of molar ratios of methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) on the preparation of methylene diphenyl-4,4'-dicarbamate.

division MPC: HCHO
Mole ratio MPC conversion rate
(%) MDC yield
(%) Example 7 4: 1 86.2 71.5 Example 9 2: 1 85 54.5 Example 10 3: 1 83.5 63 Example 11 6: 1 77.4 51.2

According to FIG. 7 and Table 5, methylene diphenyl-4,4'-dicarba when the molar ratio of methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) increased from 2: 1 to 4: 1. It can be seen that the yield of mate increased from 54.5% to 71.5%. However, it was also confirmed that the yield of methylene diphenyl-4,4'-dicarbamate dropped to 51.2% when the molar ratio of methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) was 6: 1. have.

Therefore, it can be seen that the optimum reaction conditions are suitable when the molar ratio of methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) is 4: 1.

Catalyst usage impact

8 and Table 6 show the results of the study on the effect of catalyst usage on methylene diphenyl-4,4'-dicarbamate production.

division Catalyst usage
(g) MPC conversion rate
(%) MDC yield
(%) Example 12 0.6 83.8 67.9 Example 13 0.8 83 67 Example 14 1.0 86.2 71.5 Example 15 1.2 70 56.2

According to FIG. 8 and Table 6, when the catalyst usage is 1.0 g, the yield of diphenyl-4,4'-dicarbamate increases to 71.5%, and thereafter, it is confirmed that the yield decreases when the catalyst usage increases. You can.

In summary, montmorillonite (K30-TPA) modified with tungstophosphoric acid is used as a catalyst, the reaction temperature is 90 ° C, the reaction time is 4 hours, the catalyst is 1.0 g, and methyl N-phenylcarbamate (MPC) and formaldehyde (HCHO) ), The highest yield can be obtained when diphenyl-4,4'-dicarbamate is produced under the molar ratio of 4: 1.

The scope of the present invention is indicated by the following claims rather than the above detailed description, and it should be interpreted that all changes or modified forms derived from the meaning and scope of the claims and equivalent concepts thereof are included in the scope of the present invention. do.

Claims (18)

Methylene diphenyl-4,4'-dicarba represented by the following structural formula 2 by condensation reaction using N-phenyl carbamate derivative represented by the following structural formula 1 and clay containing heteropoly acid as a catalyst: Method for producing a methylene diphenyl-4,4'-dicarbamate derivative comprising the step of preparing a mate derivative:
[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,
R ¹ are each independently a C1 to C3 alkylene group,
R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group. According to claim 1,
A method for producing a methylene diphenyl-4,4'-dicarbamate derivative, wherein R ¹ is a methylene group and R ² is a hydrogen atom. According to claim 1,
A method for producing a methylene diphenyl-4,4'-dicarbamate derivative, wherein R ¹ is an ethylene group and R ² is a methoxy group. According to claim 1,
A method for producing a methylene diphenyl-4,4'-dicarbamate derivative, wherein R ¹ is an ethylene group and R ² is a hydroxy group. According to claim 1,
The heteropoly acid is phosphotungstic acid (H ₃ PW ₁₂ O ₄₀ ), phosphomolybdic acid (H ₃ PMo ₁₂ O ₄₀ ), phosphomolybdenum tungstic acid (Phosphomolybdotungstic Acid, H ₃ PW _x Mo _{12 - x O 40 (0 <x} <12)) , and methylene diphenyl-4,4' characterized in that it comprises at least one member selected from silicon tungstate _{(Silicotungstic acid, H 4 [W} 12 SiO 40]) Method for preparing a dicarbamate derivative. The method of claim 5,
The method for producing a methylene diphenyl-4,4'-dicarbamate derivative, wherein the heteropoly acid comprises phosphotungstic acid (H ₃ PW ₁₂ O ₄₀ ). According to claim 1,
The clay contains at least one selected from montmorillonite, pyrophyllite, talc, nontronite, bititerite, saponite, kaolinite, dickite, nacrite, metahaloysite, halosite, and muscobite. Method for producing a methylene diphenyl-4,4'- dicarbamate derivative, characterized in that. The method of claim 7,
Method for producing methylene diphenyl-4,4'-dicarbamate derivative, characterized in that the clay contains montmorillonite. According to claim 1,
Method for producing a methylene diphenyl-4,4'-dicarbamate derivative characterized in that the clay on which the heteropoly acid is supported contains montmorillonite on which phosphotungstic acid is supported. According to claim 1,
Method for producing methylene diphenyl-4,4'-dicarbamate derivative, characterized in that the condensation reaction is performed by a solution reaction using a solvent. The method of claim 10,
The solvent methylene diphenyl-4,4 ', characterized in that it comprises at least one selected from dimethyl carbonate, diethyl carbonate and bis (2-methoxyethyl) carbonate (BMEC: Bis (2-methoxyethyl) carbonate) -Method for producing a dicarbamate derivative. According to claim 1,
Method for producing methylene diphenyl-4,4'-dicarbamate derivatives, characterized in that the molar ratio of the formaldehyde to the N-phenylcarbamate derivative is 1: 2 to 1: 6. According to claim 1,
Method for producing a methylene diphenyl-4,4'-dicarbamate derivative, characterized in that the catalyst is 30 to 150 parts by weight based on 100 parts by weight of the N-phenylcarbamate derivative. The method of claim 10,
Method for producing methylene diphenyl-4,4'-dicarbamate derivatives, characterized in that the solvent contains 2,000 to 6,000 parts by weight based on 100 parts by weight of the N-phenylcarbamate derivative. According to claim 1,
Method for producing a methylene diphenyl-4,4'-dicarbamate derivative, characterized in that the condensation reaction is carried out at a temperature of 50 to 200 ℃. According to claim 1,
Method for producing a methylene diphenyl-4,4'-dicarbamate derivative, characterized in that the condensation reaction is performed for 1 to 10 hours. The method of claim 1, wherein the method for producing methylene diphenyl-4,4'-dicarbamate derivative
(a ') preparing a mixture comprising a heteropoly acid-supported clay by mixing and stirring heteropoly acid, clay and water; And
(b ') preparing a heteropolyacid-supported clay by washing and drying the clay on which the heteropolyacid-supported mixture is pH 7; To
Method for producing a methylene diphenyl-4,4'-dicarbamate derivative, characterized in that it further comprises. Heteropoly acid for use as a catalyst for preparing a methylene diphenyl-4,4'-dicarbamate derivative represented by the following structural formula 2 by condensation reaction of an N-phenyl carbamate derivative represented by the following structural formula 1 with formaldehyde: This supported clay:
[Structural Formula 1]

[Structural Formula 2]

In Structural Formula 1 and Structural Formula 2,
R ¹ are each independently a C1 to C3 alkylene group,
R ² is a hydrogen atom, a hydroxy group, or a C1 to C3 alkoxy group.

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