KR101593746B1 - Organometallic compound, method for preparing the same, and method for preparing carbonic ester using the same - Google Patents

Abstract

The organometallic compound of the present invention is characterized by being represented by the following general formula (1). The organometallic compound improves the reactivity between carbon dioxide and alcohol to produce carbonic ester at a high yield.
[Chemical Formula 1]
M _a ^{3 +} [M _b (OR ₁ ) ₅ ] ₃ ^-
In the above formula (1), M _a is cerium, M _b is a Group 4 or Group 14 metal, and R ₁ is a hydrocarbon group having 1 to 10 carbon atoms.

Description

TECHNICAL FIELD The present invention relates to an organometallic compound, a method for producing the same, and a method for producing the carbonic ester using the same. BACKGROUND ART [0002]

The present invention relates to an organometallic compound, a process for producing the same, and a process for producing a carbonic ester using the same. More specifically, the present invention relates to a novel organometallic compound capable of improving the reactivity of carbon dioxide with alcohol to produce carbonic ester at a high yield, a process for producing the same, and a process for producing carbonic ester using the same.

Carbonic acid esters are monomers that are usefully used in the production of polycarbonate, and many studies related to the production thereof are under way. Conventionally, carbonic acid esters were prepared through reaction with alcohol using phosgene as a carbonyl source. However, this method has a problem of using a very toxic phosgene as well as a problem of using a chlorine-based solvent and a problem of treating a by-product neutral salt .

In order to solve the problems associated with the use of phosgene, a method for producing carbonic ester using carbon monoxide as a carbonyl source has been developed. However, when carbon monoxide is used as a carbonyl source, the reaction rate and yield are low, and the use of poisonous carbon monoxide at high pressure increases the risk of explosion and requires a great deal of cost for ensuring stability. In addition, there is a fear that side reactions such as generation of carbon dioxide may occur due to oxidation of carbon monoxide.

Also, a method has been developed in which carbon dioxide is reacted with ethylene oxide or the like to synthesize a cyclic carbonic ester and then react it with methanol to produce dimethyl carbonate. This method is an excellent method because it is not harmful to carbon dioxide which is a raw material, it uses corrosive substances such as hydrochloric acid, or rarely generates corrosive substances. However, side reactions in which ethylene glycol is produced may occur, and it is difficult to safely transport ethylene or ethylene oxide, which is a raw material of ethylene oxide, and there are limitations related to plant location and the like.

Recently, a method for producing carbonic acid ester by reacting carbon dioxide with an organic metal compound has been studied. It has been found that the carbonic ester is separated from the mixture produced by the above method and the residue can regenerate the organometallic compound through reaction with alcohol. That is, since the organic metal compound used in the reaction can be recycled, it can be reused in the carbonic ester formation reaction, and there is no problem due to transportation or the like. As such an organometallic compound, there is disclosed a compound in the form of Sn (R) ₂ (OR ') ₂ (R and R': different alkyl groups) having a center metal tin and two alkyl and alkoxy groups Patents 2010-523783, 2006-548937, 2006-513613, 2006-095140, 2005-511122, 2003-556375, 2001-396545, 2001-396537, etc.). However, the known organometallic compounds have a low reactivity and a low yield of carbonic ester production, which is a problem to be solved.

It is an object of the present invention to provide a novel organometallic compound capable of improving the reactivity of carbon dioxide with alcohol and producing carbonic ester at high yield and a process for producing the same.

Another object of the present invention is to provide a process for directly synthesizing carbonic ester from alcohols and carbon dioxide using the organometallic compound.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to organometallic compounds. The organometallic compound is characterized by being represented by the following formula (1)

[Chemical Formula 1]

M _a ^{3 +} [M _b (OR ₁ ) ₅ ] ₃ ^-

In the above formula (1), M _a is cerium, M _b is a Group 4 or Group 14 metal, and R ₁ is a hydrocarbon group having 1 to 10 carbon atoms.

In an embodiment, _Mb may be titanium (Ti), tin (Sn), or zirconium (Zr).

In an embodiment, R ₁ may be a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, or a phenyl group.

Another aspect of the present invention relates to a method for producing the organometallic compound. The process comprises reacting an alkaline metal alkoxide represented by the following general formula (2) and a metal alkoxide represented by the following general formula (3) to prepare a heterogeneous metal alkoxide represented by the following general formula (4); And reacting the dissimilar metal alkoxide and a metal halide compound represented by the following formula (5) to prepare an organometallic compound represented by the formula (1).

(2)

M _c OR ₁

(3)

M _b (OR ₁ ) ₄

[Chemical Formula 4]

M _c ⁺ [M _b (OR ₁ ) ₅ ] ^-

[Chemical Formula 5]

M _a (X) ₃

In the above Chemical Formulas 2 to 5, M _a , M _b and R ₁ are the same as defined in Formula 1, M _c is an alkali metal, and X is a halogen atom.

In an embodiment, the molar ratio of the halogenated metal compound represented by the formula (5) and the hetero metal alkoxide represented by the formula (4) may be 1: 2 to 4.

In embodiments, the reaction of the alkali metal alkoxide and the metal alkoxide may be performed at a temperature of 100 to 200 < 0 > C.

In an embodiment, the reaction of the dissimilar metal alkoxide and the metal halide compound may be carried out at a temperature of 100 to 200 ° C.

Another aspect of the present invention relates to a method for producing a carbonic ester. The production method is characterized in that an alcohol having 1 to 10 carbon atoms and carbon dioxide are reacted in the presence of the organometallic compound.

In an embodiment, the reaction can be carried out at a temperature of 130 to 200 DEG C and a pressure of 10 to 200 bar.

The present invention relates to a novel organometallic compound capable of improving the reactivity between carbon dioxide and alcohol to produce carbonic ester at a high yield, a process for producing the same, a process for directly synthesizing carbonic ester from alcohols and carbon dioxide using the organometallic compound The present invention provides the effect of the present invention.

1 is a ¹ H-NMR spectrum of an organometallic compound prepared according to Production Example 1 of the present invention.

Hereinafter, the present invention will be described in detail.

The organometallic compound according to the present invention can be represented by the following general formula (1).

[Chemical Formula 1]

M _a ^{3 +} [M _b (OR ₁ ) ₅ ] ₃ ^-

Wherein M _a is cerium and M _b is a Group 4 or Group 14 metal, preferably titanium (Ti), tin (Sn), or zirconium (Zr), R ₁ is a hydrocarbon having 1 to 10 carbon atoms For example, an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group or a phenyl group. Here, the metal atoms (M _a and M _b ) and the oxygen atom (O) of the alkoxy group (OR ₁ ) may be connected by a covalent bond and a coordination bond,

[Formula 1a]

In the above formula (1a), M _a , M _b and R ₁ are as defined in the above formula (1), and the arrows indicate coordination bonding.

The organometallic compound of the present invention may be prepared by reacting an alkali metal alkoxide represented by the following general formula (2) and a metal alkoxide represented by the following general formula (3) to prepare a heterometallic alkoxide represented by the following general formula (4); And reacting the dissimilar metal alkoxide and a metal halide compound represented by the following formula (5) to prepare an organometallic compound represented by the above formula (1).

(2)

M _c OR ₁

(3)

M _b (OR ₁ ) ₄

[Chemical Formula 4]

M _c ⁺ [M _b (OR ₁ ) ₅ ] ^-

[Chemical Formula 5]

M _a (X) ₃

Wherein M _a , M _b and R ₁ are the same as defined in Formula 1, M _c is an alkali metal such as sodium (Na), potassium (K) or the like, X is a halogen atom, For example, a chlorine atom (Cl), a bromine atom (Br), or the like.

In an embodiment, the alkali metal alkoxide represented by the general formula (2) and the metal alkoxide represented by the general formula (3) are added in a molar ratio of, for example, 1: 0.5 to 2, preferably in an equimolar ratio, Preferably at a temperature of 110 to 150 ° C, for example, for 2 to 4 hours to produce a bimetal alkoxide represented by the general formula (4).

Next, a halogenated metal compound represented by the formula (5) is introduced into the prepared dissimilar metal alkoxide as shown in Reaction Scheme 1 below, and then, at a temperature of 100 to 200 ° C, preferably 110 to 150 ° C, for example, 10 And then refluxed for 15 hours to prepare an organometallic compound represented by the above formula (1). In addition, the produced organometallic compound can be obtained in a solid state through a conventional process such as cooling, filtration, and purification.

[Reaction Scheme 1]

In the above process, the molar ratio of the metal halide compound represented by Formula 5 and the hetero metal alkoxide represented by Formula 4 may be, for example, 1: 1 to 5, preferably 1: 2 to 4, 1: 3 to 3.5. By-products can be minimized in this range.

The method for producing a carbonic ester using an organometallic compound according to the present invention is characterized in that carbonic ester is directly produced by reacting an environmentally friendly raw material such as an alcohol having 1 to 10 carbon atoms and carbon dioxide in the presence of the organometallic compound.

The alcohol used in the present invention may be represented by the following formula (6).

[Chemical Formula 6]

R ₂ OH

In Formula 6, R ₂ is a hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms.

Specific examples of the alcohol include, but are not limited to, methanol, ethanol, propanol, butanol, pentanol, hexanol, and phenol.

The carbonic ester may be represented by the following general formula (7).

(7)

R ₂ OCOOR ₂

In Formula 7, R ₂ is the same as defined in Formula 6.

The reaction can be carried out by a conventional batch reaction and is carried out, for example, at a temperature of from 130 to 200 DEG C, preferably from 140 to 190 DEG C and at a pressure of from 10 to 200 bar, preferably from 40 to 150 bar . In this range, the reaction rate is fast and the carbonic ester can be produced with a high yield.

Typically, the batch reaction is carried out in consideration of the conversion rate and the reactor volume, and is a liquid phase process that is not superheated.

In addition, the reaction of the present invention uses a liquid reaction product of an alcohol having 1 to 10 carbon atoms, carbon dioxide and a solid organometallic compound as gas phase reactants, and requires no additional solvent. That is, it may be a homogeneous reaction in which carbon dioxide and an organic metal compound are melted and reacted with the alcohol. Stirring of the reactor can be carried out using a magnetic bar or the like, for example, at a stirring speed of 300 to 1,000 rpm, preferably 400 to 500 rpm and a reaction time of 0.5 to 24 hours, preferably 1 to 3 hours However, it is preferable to perform in the region where the mass transfer of the interface between the carbon dioxide and the alkyl alcohol is maximized in consideration of the state of the organometallic compound and the viscosity of the solvent. Such a reaction can be easily carried out by a person having ordinary skill in the art to which the present invention belongs.

In an embodiment, the organometallic compound may be used in an amount of 1 to 30 moles, preferably 5 to 15 moles, per 100 moles of the alkyl alcohol. Carbonic acid esters can be produced at a high yield in the above range.

In addition, the pressure of the carbon dioxide may be 10 to 200 bar, preferably 40 to 150 bar. In the above range, the carbonic ester can be produced in the above range at a high yield.

The method for producing a carbonic ester of the present invention is economical because a separate regeneration step of an organometallic compound is not required.

Hereinafter, the present invention will be described in more detail by way of examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Example

Manufacturing example  1: Preparation of organometallic compounds

0.6 g (15 mmol) of potassium was reacted with 11.5 g (155 mmol) of 1-butanol at room temperature for 20 minutes, refluxed at 120 ° C for 1 hour and cooled to give potassium butoxide (KOBu). 5.2 g (15 mmol) of Ti (OBu) ₄ as a metal alkoxide was added to 1.7 g (15 mmol) of the prepared potassium butoxide (KOBu) and 1-butanol mixture and the mixture was refluxed at 120 ° C. for 3 hours, A heterometallic alkoxide (KTi (OBu) ₅ ) represented by the following formula 4a was prepared. 1.25 g (5 mmol) of cerium chloride (CeCl ₃ ) was added to the prepared double metal alkoxide (6.8 g, 15 mmol) and 1-butanol mixture and the mixture was refluxed at 120 ° C. for 12 hours in a nitrogen atmosphere. After purification, the solvent was evaporated to obtain an organometallic compound represented by the following formula (1b) in the form of a white solid (yield: 23%). The metal and alkoxy groups of the organometallic compound thus prepared were confirmed by using an inductively coupled plasma spectrometer (ICP-AES) and nuclear magnetic resonance spectroscopy (NMR). 1 and Table 1 show ¹ H-NMR spectrum and ICP-AES elemental analysis results (Ce: Ti (molar ratio) = about 1: 3).

[Chemical Formula 4a]

K ⁺ [M _b (OBu) ₅ ] ^-

[Chemical Formula 1b]

Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^-

Ce Ti Chemical food (F.W) 140.12 g / mol 47.88 g / mol Content (% by weight) 11.02 10.95

Example  One

5 g (3.6 mmol) of the organometallic compound (Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^- ) represented by the above reaction formula 1a and 27.2 g (367.3 mmol) of 1-butanol were added to an internal 75 ml autoclave reactor having an external heater mmol) was added, and the mixture was heated to 150 ° C. at the same time as the stirring. Carbon dioxide was added to 120 bar, and the mixture was reacted at 150 ° C. and 120 bar for 1 hour. After the carbon dioxide was vented to return to atmospheric pressure, the reaction liquid was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 75%.

Example  2

The reaction was carried out in the same manner as in Example 1 except that the reaction temperature was 180 캜. After completion of the reaction, the reaction solution was analyzed by gas chromatography to find that di-n-butyl carbonate was obtained in a yield of 127%.

Example  3

The reaction was carried out in the same manner as in Example 1 except that the reaction pressure was 60 bar. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 69%.

Example  4

The reaction was carried out in the same manner as in Example 2 except that the reaction pressure was 60 bar. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 106%.

Comparative Example  One

The reaction was carried out in the same manner as in Example 1 except that 5 g (14.7 mmol) of a compound represented by the following formula (8a) (Ti [OBu] ₄ ) was used as an organometallic compound. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 30%.

[Chemical Formula 8a]

Comparative Example  2

The reaction was carried out in the same manner as in Comparative Example 1 except that the reaction temperature was 180 캜. After completion of the reaction, the reaction liquid was analyzed by gas chromatography, and it was confirmed that di-n-butyl dicarbonate was obtained in a yield of 98%.

Comparative Example  3

The reaction was carried out in the same manner as in Comparative Example 1, except that the reaction pressure was 60 bar. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 20%.

Comparative Example  4

The reaction was carried out in the same manner as in Comparative Example 3, except that the reaction temperature was 180 캜. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in 82% yield.

Comparative Example  5

Example 1 was repeated except that 5 g (13.3 mmol) of the compound represented by the following formula (8b) (Bu ₂ Sn (OBu) ₂ ) was used as the organometallic compound and 24.4 g (329.5 mmol) The reaction was carried out in the same manner. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 49%.

[Formula 8b]

Comparative Example  6

The reaction was carried out in the same manner as in Comparative Example 5 except that the reaction temperature was 180 캜. After completion of the reaction, the reaction solution was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 69%.

Comparative Example  7

The reaction was carried out in the same manner as in Comparative Example 5 except that the reaction pressure was 60 bar. After completion of the reaction, the reaction liquid was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 50%.

Comparative Example  8

The reaction was carried out in the same manner as in Comparative Example 7, except that the reaction temperature was 180 占 폚. After completion of the reaction, the reaction liquid was analyzed by gas chromatography, and it was confirmed that di-n-butyl carbonate was obtained in a yield of 60%.

The reaction conditions and the yield of carbonic ester are shown in Table 2 below.

Organometallic compound Alcohol Reaction temperature
(° C) Reaction pressure
(bar) Reaction time
(h) yield
(%) Kinds mmol g mmol g Example 1 Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^- 3.6 5 367.3 27.2 150 120 One 75 Example 2 Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^- 3.6 5 367.3 27.2 180 120 One 127 Example 3 Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^- 3.6 5 367.3 27.2 150 60 One 69 Example 4 Ce ^{3 +} [Ti (OBu) ₅ ] ₃ ^- 3.6 5 367.3 27.2 180 60 One 106 Comparative Example 1 Ti [OBu] ₄ 14.7 5 367.3 27.2 150 120 One 68 Comparative Example 2 Ti [OBu] ₄ 14.7 5 367.3 27.2 180 120 One 98 Comparative Example 3 Ti [OBu] ₄ 14.7 5 367.3 27.2 150 60 One 61 Comparative Example 4 Ti [OBu] ₄ 14.7 5 367.3 27.2 180 60 One 82 Comparative Example 5 This is ₂ Sn (OBu) ₂ 13.2 5 329.7 24.5 150 120 One 55 Comparative Example 6 This is ₂ Sn (OBu) ₂ 13.2 5 329.7 24.5 180 120 One 69 Comparative Example 7 This is ₂ Sn (OBu) ₂ 13.2 5 329.7 24.5 150 60 One 52 Comparative Example 8 This is ₂ Sn (OBu) ₂ 13.2 5 329.7 24.5 180 60 One 60

Property evaluation method

(1) Evaluation of yield: After the reaction, the reaction solution was analyzed by gas chromatography.

Carbonic acid ester yield (%) = (moles of produced carbonate ester / number of moles of organic metal compound added) x 100

From the results shown in Table 1, it can be seen that the organic metal compounds of the present invention can produce carbonic ester at a higher yield than conventional organometallic compounds (Comparative Examples 1 to 8) under the same reaction conditions.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (9)

An organometallic compound represented by the following Chemical Formula 1:
[Chemical Formula 1]
M _a ^{3 +} [M _b (OR ₁ ) ₅ ] ₃ ^-
In the above formula (1), M _a is cerium, M _b is a Group 4 or Group 14 metal, and R ₁ is a hydrocarbon group having 1 to 10 carbon atoms.
The organometallic compound according to claim 1, wherein M _b is titanium (Ti), tin (Sn), or zirconium (Zr).
The organometallic compound according to claim 1, wherein R ₁ is a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group or a phenyl group.
Reacting an alkali metal alkoxide represented by the following general formula (2) and a metal alkoxide represented by the following general formula (3) to prepare a heterogeneous metal alkoxide represented by the following general formula (4); And
Reacting the dissimilar metal alkoxide and a metal halide compound represented by the following formula (5) to produce an organometallic compound represented by the following formula (1): < EMI ID =
[Chemical Formula 1]
M _a ^{3 +} [M _b (OR ₁ ) ₅ ] ₃ ^-
Wherein M _a is cerium, M _b is a Group 4 or Group 14 metal, and R ₁ is a hydrocarbon group having 1 to 10 carbon atoms;
(2)
M _c OR ₁
(3)
M _b (OR ₁ ) ₄
[Chemical Formula 4]
M _c ⁺ [M _b (OR ₁ ) ₅ ] ^-
[Chemical Formula 5]
M _a (X) ₃
In the above Chemical Formulas 2 to 5, M _a , M _b and R ₁ are the same as defined in Formula 1, M _c is an alkali metal, and X is a halogen atom.
The method of claim 4, wherein the molar ratio of the halogenated metal compound represented by Formula 5 to the hetero metal alkoxide represented by Formula 4 is 1: 2 to 4.
5. The method of claim 4, wherein the reaction of the alkali metal alkoxide and the metal alkoxide is performed at a temperature of 100 to 200 ° C.
5. The method of claim 4, wherein the reaction of the dissimilar metal alkoxide and the metal halide compound is performed at a temperature of 100 to 200 ° C.
A process for producing a carbonic ester, which comprises reacting an alcohol having 1 to 10 carbon atoms and carbon dioxide in the presence of the organometallic compound according to any one of claims 1 to 3.
9. The method according to claim 8, wherein the reaction is carried out at a temperature of 130 to 200 DEG C and a pressure of 10 to 200 bar.

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