METHOD FOR CATALYZING REACTION OF EPOXIDE COMPOUND AND CARBON DIOXIDE WITH CATALYST

Abstract

A method for catalyzing a reaction of an epoxide compound and carbon dioxide with a catalyst. The catalyst comprises at least one compound of formula (1):

Description

FIELD

The present disclosure relates to the technical field of chemical synthesis, and specifically relates to a method for catalyzing a reaction of an epoxide compound and carbon dioxide with a catalyst.

BACKGROUND

Cyclic carbonate is widely used for example as an organic solvent, a synthetic fiber processing agent, a pharmaceutical raw material, a cosmetic additive, and an electrolyte solvent for lithium batteries, and may be obtained from an addition reaction of carbon dioxide, which usually needs a catalyst. Existing catalysts for the addition reaction have defects, such as low catalytic activity, poor stability, harsh reaction condition requirement, toxicity, various by-products, and difficulty in product purification.

Therefore, there is still a need to develop catalysts and methods capable of catalyzing an addition reaction of carbon dioxide and the epoxide under environmentally friendly and mild conditions.

SUMMARY

In a first aspect, the present disclosure provides in embodiments a method for catalyzing an addition reaction of an epoxide compound and carbon dioxide with a catalyst. The catalyst includes at least one compound of formula (1):

• • where R is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; X is selected from halogens; B is selected from nitrogen, or phosphorus; A is selected from any of the following formulae with a sign * representing a bonding position:

In some embodiments, R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15, for example 1 to 10, carbon atoms.

In some embodiments, X is selected from F, Cl, Br, or I, for example from Br or Cl.

In some embodiments, the compound of formula (1) includes at least one of:

In some embodiments, the catalyst further includes at least one compound of formula (2):

• • where R1 is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; Y is selected from halogens; B′ is selected from nitrogen, or phosphorus; A′ is selected from any of the following formulae with a sign * representing a bonding position:

In some embodiments, R1 is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15, for example 1 to 10, carbon atoms; and/or, Y is selected from F, Cl, Br, or I, for example from Br or Cl.

In some embodiments. the compound of formula (2) includes at least one of:

In some embodiments, a molar ratio of the compound of formula (1) to the compound of formula (2) is in a range of 100:(1 to 12).

In some embodiments, the epoxide compound is selected from at least one compound of formula (3):

• • where when R2=H, R3 is selected from H, CH₃, CH₂Cl, C₂H₃, C₄H₉O, C₄H₉, C₆H₅, or C₈H₇O; when R2≠H, the epoxide compound is cyclohexene oxide.

In some embodiments, a molar ratio of the catalyst to the epoxide compound is in a range of (0.5×10⁻³ to 1.5×10⁻²):1.

In some embodiments, the reaction is performed at a temperature of 100 to 200° C., and/or under a pressure of 1 to 5 MPa.

In a second aspect, the present disclosure further provides in embodiments, a catalyst including at least one compound of formula (1) and at least one compound of formula (2):

• • where R is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; X is selected from halogens; B is selected from nitrogen, or phosphorus; and A is selected from any of the following formulae with a sign * representing a bonding position:

• • R1 is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; Y is selected from halogens; B′ is selected from nitrogen, or phosphorus; and A′ is selected from any of the following formulae with a sign * representing a bonding position:

In some embodiments, R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15, for example 1 to 10, carbon atoms; and/or, X is selected from F, Cl, Br, or I, for example from Br or Cl.

In some embodiments, the compound of formula (1) includes at least one of:

In some embodiments. the compound of formula (2) includes at least one of:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a gas chromatogram of a product catalyzed by a catalyst of the present disclosure.

DETAILED DESCRIPTION

In the following embodiments of the present disclosure, if a condition for an experimental method or device is not specified, it is usually in accordance with conventional conditions, or conditions recommended by manufacturers. Various common chemicals used in the embodiments are commercially available products.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Terms used in the specification of the present disclosure are only for the purpose of describing specific embodiments, and are not intended to limit the present disclosure.

Terms “including”, “having”, and any variations thereof of the present disclosure are intended to cover non-exclusive inclusions. For example, a process, a method, an apparatus, a product, or a device that includes a series of steps is not limited to the listed steps or modules only, but may further include steps that are not listed, or may include other steps inherent to the process, method, product or device.

In the present disclosure, the term “a plurality of” refers to two or more, and term “and/or” describes a relationship among associated objects, indicating that there may be three relationships. For example, A and/or B, may include three cases of A existing alone, A and B existing at the same time, and B existing alone. The character “/” generally indicates that the associated objects is in a relationship of being connected by “or”.

This embodiment provides in embodiments a method for catalyzing a reaction of an epoxide compound and carbon dioxide with a catalyst. The catalyst includes at least one compound of formula (1):

• • where R is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; X is selected from halogens; B is selected from nitrogen, or phosphorus; A is selected from any of the following formulae with a sign * representing a bonding position:

The compound of formula (1) is a catalyst with a symmetrical structure, and has a single type of reaction sites. It can be used in catalyzing the reaction of carbon dioxide and the epoxide compound to prepare a cyclic carbonate, and side reactions can be effectively reduced, thus resulting in a high final product purity and few impurity species.

In some embodiments, the compound of formula (1) includes, but is not limited to:

In another embodiment of the present disclosure, the catalyst further includes at least one compound of formula (2):

• • where R1 is selected from an alkyl group, an alkenyl group, a halohydrocarbyl group, an aromatic hydrocarbyl group, an imidazolyl group, or a heteroaromatic hydrocarbyl group; Y is selected from halogens; B′ is selected from nitrogen, or phosphorus; A′ is selected from any of the following formulae with a sign * representing a bonding position:

After a lot of researches, the inventors of the present disclosure found that a catalytic mechanism of the compound of formula (2) is similar to that of the compound of formula (1), but it has a stronger adsorption to the oxygen free radicals formed from the epoxides (in which the ring of the epoxide is opened and is further reacted with halogen). When the compound of formula (1) is compounded with a small amount of the compound of formula (2), the above-mentioned oxygen free radicals can be transferred, and the compound of formula (1) can be released, thus reducing decomposition caused by nucleophilic adsorption. When the compound of formula (1) and the compound of formula (2) are used as a composite catalyst in a proper proportion, the stability of the catalyst used for cycles can be improved, and a good catalytic activity can still be maintained after a plurality of cycles.

In some embodiments, a molar ratio of the compound of formula (1) to the compound of formula (2) in the composite catalyst is in a range of 100:(1 to 12). If the content of the compound of formula (2) is too small, the effect of increasing the stability will not be realized. If the content is too high, an amount of impurities in the product will be increased.

In some embodiment, the compound of formula (2) includes, but is not limit to:

In some embodiments, the composite catalyst includes the compound 1 and the compound 22, or the compound 2 and the compound 23, or the compound 9 and the compound 24.

The general reaction formula of the compound of formula (1) in the present disclosure is as follows.

The general reaction formula of the compound of formula (2) in the present disclosure is the same as that of the compound of formula (1), except that a raw material

of the reaction is replaced by one material of a similar formula with one R determined as H.

With the formulae of the compounds of formula (1) and formula (2), preparation methods of the above-mentioned compounds can be prepared according to the common knowledge in the chemical synthesis field. For example, the compound 1 can be prepared as follows.

In some embodiments, the epoxide compound is selected from at least one compound of formula (3):

• • where when R2=H, R3 is selected from H (ethylene oxide), CH₃ (propylene oxide), CH₂Cl (epichlorohydrin), C₂H₃ (butadiene monoxide), C₄H₉O (2-propoxymethyloxirane), C₄H₉ (1,2-epoxyhexane), C₆H₅ (styrene oxide), or C₈H₇O (2-(phenoxymethyl)oxirane); when R2≠H, the epoxide compound is cyclohexene oxide.

In some embodiments, the general formula of the catalyst for catalyzing the reaction of the epoxide compound and carbon dioxide is as follows:

• • where when R2=H, R3 is selected from H (ethylene oxide), CH₃ (propylene oxide), CH₂Cl (epichlorohydrin), C₂H₃ (butadiene monoxide), C₄H₉O (2-propoxymethyloxirane), C₄H₉ (1,2-epoxyhexane), C₆H₅ (styrene oxide), or C₈H₇O (2-(phenoxymethyl)oxirane); when R2≠H, the epoxide compound is cyclohexene oxide.

In some embodiments, a molar ratio of the catalyst to the epoxide compound is in a range of (0.5×10⁻³ to 1.5×10⁻²):1. For example, the molar ratio of the catalyst to the epoxide compound is in a range of (0.5×10⁻³ to 5×10⁻³):1.

In some embodiments, a temperature of the reaction is in a range of 100 to 200° C. For example, the temperature of the reaction is in a range of 120 to 160° C.

In some embodiments, a pressure of the reaction is in a range of 1 to 5 MPa. For example, the pressure of the reaction is in a range of 1 to 3 MPa.

The present disclosure is further described with reference to the following examples.

EXAMPLE 1

In this example, a method for preparing a cyclic carbonate is provided, and a reaction formula of the method is as follows:

Experimental groups 1 to 10 and control groups 1 to 2 are provided. A preparation method for the experimental groups 1 to 10 includes the following operations (1) to (6).

(1) For each of experimental groups 1 to 10, a catalyst is added in a 100 mL stainless steel reactor, and a type and an amount of the catalyst is shown in Table 1.

(2) 44 g ethylene oxide (1 mol) is introduced into the stainless steel reactor.

(3) The reactor is sealed and filled with carbon dioxide at any appropriate pressure to make a pressure of the system to be about 1.0 MPa.

(4) The temperature is slowly increased by a temperature controller, and a final temperature is shown in Table 1.

(5) The pressure of carbon dioxide is controlled to be 1 to 5 Mpa, for example 1 to 3 MPa, as shown in Table 1.

(6) After the reaction is the completed, the reactor is cooled to the room temperature, the product is discharged from the reactor. Remaining carbon dioxide is absorbed with saturated sodium carbonate solution. Liquid obtained after the reaction is decompressed and distilled to obtain the product cyclic carbonate.

For control groups 1 to 2, the preparation method for the control groups 1 to 2 is the same as that for the experiment group 1 (as shown in Table 1) except for the type of the catalyst. Control groups 1 and 2 use the following catalysts, Control 1 and Control 2, respectively.

TABLE 1
		Adding	Reaction	Reaction	Reaction
Group	Catalyst	amount	time	pressure	temperature
Experimental	compound 1	1 mmol	2 h	2	Mpa	140° C.
group 1
Experimental	compound 4	1 mmol	2 h	2	Mpa	120° C.
group 2
Experimental	compound 1	0.5 mmol	2 h	2.5	Mpa	140° C.
group 3
Experimental	compound 2	1 mmol	2 h	3	Mpa	140° C.
group 4
Experimental	compound 6	1 mmol	2 h	1.5	Mpa	140° C.
group 5
Experimental	compound 12	12 mmol	2 h	3.5	Mpa	130° C.
group 6
Experimental	compound 15	1 mmol	2 h	2	Mpa	160° C.
group 7
Experimental	compound 17	5 mmol	2 h	4.5	Mpa	175° C.
group 8
Experimental	compound 20	15 mmol	2 h	2	Mpa	105° C.
group 9
Experimental	compound 1 +	1 mmol	1.5 h	2	Mpa	140° C.
group 10	compound 22
Control	Control 1	1 mmol	2 h	2	Mpa	140° C.
group 1
Control	Control 2	1 mmol	2 h	2	Mpa	140° C.
group 2

In Table 1, a molar ratio of the compound I to the compound 22 in the composite catalyst used in the experimental group 10 is 20:1.

Test results of the above experimental groups and control groups are shown in Table 2 below. Gas chromatographic data of a product of the experimental group 1 is shown in FIG. 1.

TABLE 2
			Final product	Impurity
Group	Selectivity	Yield	purity	species
Experimental	98.0%	99.1%	99.95%	5
group 1
Experimental	97.3%	96.3%	99.93%	5
group 2
Experimental	98.1%	97.4%	99.94%	5
group 3
Experimental	96.2%	95.7%	99.74%	5
group 4
Experimental	95.2%	95.0%	99.38%	6
group 5
Experimental	95.3%	95.1%	99.43%	6
group 6
Experimental	95.0%	94.5%	99.30%	6
group 7
Experimental	95.4%	95.2%	99.45%	6
group 8
Experimental	95.1%	94.8%	99.36%	6
group 9
Experimental	99.2%	99.1%	99.94%	7
group 10
Control	96.6%	94.5%	99.00%	9
group 1
Control	95.8%	94.1%	98.53%	10
group 2
Note:
the number of impurity species refers to the number of impurity peaks except for peaks of the cyclic carbonate and acetonitrile blank.

The above results show that the preparation methods for the experimental groups 1 to 10 have advantages of good selectivity, yield, and final product purity, as well as few impurity species. Compared with the result of the experimental group 1, the selectivities, yields and final product purities of the control groups 1 and 2 are inferior, and more impurity species are obtained in control groups 1 and 2. It shows that the catalyst used in the preparation method of the present disclosure can effectively reduce the side reactions, improve the final product purity and reduce the impurity species.

EXAMPLE 2

In this example, a method for preparing a cyclic carbonate is provided, and a reaction formula of the method is as follows:

Experimental groups 11 to 17 and control groups 3 to 4 are provided. Preparation method for the experimental groups Il to 17 includes the following operations (1) to (6).

(1) For each of the experimental groups 11 to 17, a catalyst is added in a 100 mL stainless steel reactor, and a type and an amount of the catalyst is shown in Table 3.

(2) 58.0 g methyl ethylene oxide (1 mol) is introduced into the stainless steel reactor.

(3) The reactor is sealed and filled with carbon dioxide at any appropriate pressure.

(4) The temperature is slowly increased by a temperature controller, and a final temperature is shown in Table 3.

(5) The pressure of carbon dioxide is controlled to a value as shown in Table 3.

(6) After the reaction is the completed, the reactor is cooled to the room temperature, the product is discharged from the reactor. Remaining carbon dioxide is absorbed with saturated sodium carbonate solution. Liquid obtained after the reaction is decompressed and distilled to obtain the product cyclic carbonate.

For control groups 3 and 4: as shown in Table 3, the preparation method for the control group 3 is the same as that for the experimental group 11 except for the type of the catalyst, and the control group 3 uses the catalyst Control 1. The preparation method in the control group 4 is the same as that for the experimental group 16 except for the type of the catalyst, and the control group 4 uses the catalyst Control 2.

TABLE 3
		Adding	Reaction	Reaction	Reaction
Group	Catalyst	amount	time	pressure	temperature
Experimental	compound 1	1 mmol	2 h	2	Mpa	140° C.
group 11
Experimental	compound 1	1 mmol	2 h	2	Mpa	120° C.
group 12
Experimental	compound 5	0.5 mmol	2 h	2.5	Mpa	140° C.
group 13
Experimental	compound 2	1 mmol	2 h	3	Mpa	140° C.
group 14
Experimental	compound 3	1 mmol	2 h	1.5	Mpa	140° C.
group 15
Experimental	compound 1	1 mmol	2 h	2	Mpa	160° C.
group 16
Experimental	compound 2 +	1 mmol	1.5 h	2	Mpa	140° C.
group 17	compound 23
Control	Control 1	1 mmol	2 h	2	Mpa	140° C.
group 3
Control	Control 2	1 mmol	2 h	2	Mpa	160° C.
group 4

In Table 3, a molar ratio of the compound 2 to the compound 23 in the composite catalyst used in the experimental group 17 is 100:10.

Test results of selectivity, yield, final product purity and impurity quantity of the above experimental groups and control groups are shown in Table 4 below:

TABLE 4
			Final product	Impurity
Group	Selectivity	Yield	purity	species
Experimental	96.8%	96.7%	99.85%	5
group 11
Experimental	95.6%	95.4%	99.26%	5
group 12
Experimental	92.7%	91.0%	99.63%	5
group 13
Experimental	92.1%	90.8%	98.75%	6
group 14
Experimental	91.0%	88.9%	99.07%	6
group 15
Experimental	96.5%	96.1%	99.79%	5
group 16
Experimental	92.4%	91.1%	99.01%	7
group 17
Control	92.6%	93.9%	98.21%	9
group 3
Control	91.6%	93.4%	98.03%	10
group 4
Note:
the number of impurity species refers to the number of impurity peaks except for peaks of the cyclic carbonate and acetonitrile blank.

The above results show that the preparation methods for the experimental groups 11 to 17 have advantages of good selectivity, yield and final product purity, as well as few impurity species. Compared with the experimental group 11, the selectivity, yield and final product purity of the control group 3 are inferior, and more impurity species are obtained in control group 3. Compared with the experimental group 16, the selectivity, yield and final product purity of the control group 4 are inferior, and more impurity species are obtained in control group 4. It shows that the catalyst used in the preparation method of the present disclosure can effectively reduce the side reactions, improve the final product purity and reduce the impurity species.

EXAMPLE 3

In this example, a method for preparing a cyclic carbonate is provided, and a reaction formula of the preparation method is as follows:

Experimental groups 18 to 24 and control groups 5 to 6 are provided. Preparation methods for the experimental groups 18 to 24 includes the following operations (1) to (6).

(1) A catalyst is added in a 100 mL stainless steel reactor at a specific content as shown in Table 5.

(2) 77 g 1,3-diazacyclopentadiene oxirane (0.5 mol) is introduced into the stainless steel reactor.

(3) The reactor is sealed and filled with carbon dioxide at any appropriate pressure.

(4) The temperature is slowly increased by a temperature controller, and a final temperature is shown in Table 5.

(5) The pressure of the carbon dioxide is controlled to a value as shown in Table 5.

(6) After the reaction is the completed, the reactor is cooled to the room temperature, the product is discharged from the reactor. Remaining carbon dioxide is absorbed with saturated sodium carbonate solution. Liquid obtained after the reaction is decompressed and distilled to obtain the product cyclic carbonate.

For control groups 5 and 6: as shown in Table 5, the preparation method for the control group 5 is the same as that for the experimental group 23 except for the type of the catalyst, and the control group 5 uses the catalyst Control 1. The preparation method in the control group 6 is the same as that for the experimental group 18 except for the type of the catalyst, and the control group 6 uses the catalyst Control 2.

TABLE 5
		Adding	Reaction	Reaction	Reaction
Group	Catalyst	amount	time	pressure	temperature
Experimental	compound 1	1 mmol	2 h	2	Mpa	140° C.
group 18
Experimental	compound 7	1 mmol	2 h	2	Mpa	120° C.
group 19
Experimental	compound 1	0.5 mmol	2 h	2.5	Mpa	140° C.
group 20
Experimental	compound 2	1 mmol	2 h	3	Mpa	140° C.
group 21
Experimental	compound 8	1 mmol	2 h	1.5	Mpa	140° C.
group 22
Experimental	compound 1	1 mmol	2 h	2	Mpa	150° C.
group 23
Experimental	compound 9 +	1 mmol	1.5 h	2	Mpa	140° C.
group 24	compound 24
Control	Control 1	1 mmol	2 h	2	Mpa	150° C.
group 5
Control	Control 2	1 mmol	2 h	2	Mpa	140° C.
group 6

In Table 5, a molar ratio of the compound 9 to the compound 24 in the composite catalyst used in the experimental group 24 is 100:4.

Test results of the above experimental groups and control groups are shown in Table 6 below:

TABLE 6
			Final product	Impurity
Group	Selectivity	Yield	purity	species
Experimental	93.4%	90.7%	99.65%	7
group 18
Experimental	88.5%	87.9%	99.48%	7
group 19
Experimental	90.8%	88.3%	99.73%	7
group 20
Experimental	80.9%	85.9%	98.24%	8
group 21
Experimental	76.8%	83.7%	97.91%	8
group 22
Experimental	93.6%	91.1%	99.71%	7
group 23
Experimental	96.5%	95.1%	99.94%	7
group 24
Control	80.3%	75.7%	98.29%	14
group 5
Control	66.8%	38.6%	98.01%	14
group 6
Note:
the number of impurity species refers to the number of impurity peaks except for peaks of the cyclic carbonate and acetonitrile blank.

The above results show that the preparation methods for the experimental groups 18 to 24 have advantages of good selectivity, yield and final product purity, as well as few impurity species. Compared with the experimental group 18, the selectivity, yield and final product purity of the control group 6 are inferior, and more impurity species are obtained in control group 6. Compared with the experimental group 23, the selectivity, yield and final product purity of the control group 5 are inferior, and more impurity species are obtained in control group 5. It shows that the catalyst used in the preparation method of the present disclosure can effectively reduce the side reactions, improve the final product purity and reduce the impurity species.

EXAMPLE 4

In this example, a catalytic stability of a catalyst is analyzed.

Experimental groups 25 to 30 and control groups 7 to 8 are provided. The preparation methods for all these groups are the same as that for the experimental group 1 in Example 1 except that the catalysts used are different. The catalyst used in each group is shown in Table 7.

TABLE 7
			Adding	Reaction	Reaction	Reaction
Group	Catalyst	Mole ratio	amount	time	pressure	temperature
Experimental	compound 1	—	1 mmol	2 h	2 Mpa	140° C.
group 25
Experimental	compound 1 +	compound
group 26	compound 22	1:compound 22 =
		100:5
Experimental	compound 2 +	compound
group 27	compound 23	2:compound 23 =
		100:10
Experimental	compound 9 +	compound
group 28	compound 24	9:compound 24 =
		100:4
Experimental	compound 9 +	compound
group 29	compound 24	9:compound 24 =
		100:0.5
Experimental	compound 9 +	compound
group 30	compound 24	9:compound 24 =
		100:13
Control group 7	Control 1	—
Control group 8	Control 2	—

After separating off newly formed cyclic carbonate. ethylene oxide and carbon dioxide are introduced into the reaction system for reaction repeatedly The number of cycles of the catalyst and corresponding test results are shown in Table 8.

TABLE 8
	Number of			Final product	Impurity
Group	cycles	Selectivity	Yield	purity	species
Experimental	3	97.9%	99.0%	99.95%	5
group 25	4	98.0%	98.9%	99.94%	5
	5	95.2%	96.9%	99.90%	6
Experimental	3	99.8%	99.5%	99.99%	7
group 26	4	99.7%	99.5%	99.98%	7
	5	99.8%	99.4%	99.99%	7
Experimental	3	98.6%	99.5%	99.99%	7
group 27	4	98.6%	99.3%	99.99%	7
	5	98.5%	99.3%	99.97%	7
Experimental	3	98.8%	98.6%	99.99%	7
group 28	4	98.6%	98.4%	99.98%	7
	5	98.7%	98.3%	99.96%	8
Experimental	3	98.8%	98.6%	99.89%	7
group 29	4	98.6%	98.4%	99.88%	7
	5	97.7%	97.8%	99.59%	7
Experimental	3	98.8%	98.6%	99.99%	7
group 30	4	98.6%	98.5%	99.98%	8
	5	98.6%	98.4%	99.98%	8
Control	3	96.5%	94.4%	98.98%	10
group 7	4	96.3%	94.2%	98.89%	11
	5	94.4%	92.8%	98.78%	11
Control	3	95.2%	94.0%	98.11%	11
group 8	4	95.0%	93.9%	98.08%	12
	5	94.6%	93.7%	98.01%	13
Note:
the number of impurity species refers to the number of impurity peaks except for peaks of the cyclic carbonate and acetonitrile blank.

From the above results, it can be seen that compared with the catalysts used in the control groups, the catalysts of the present disclosure have higher catalytic activity and better catalytic stability after cycles.

It can be seen from the comparison between the experimental group 28 and the experimental groups 29 to 30 that the ratio of the compound of formula (1) to the compound of formula (2) in the composite catalyst may affect the catalytic effect of the composite catalyst. If the content of the compound of formula (2) in the composite catalyst is too low (the experimental group 29), the effect of increased stability may not be that good. If the content is too high (the experimental group 30), the impurity species may increase.

It can be seen from the comparison between the experimental group 25 and the experimental groups 26 to 28 that the catalytic stability of the composite catalyst composed of the compound of formula (1) and the compound of formula (2) is better than that of the single-component catalyst, i.e., the compound of formula (1). Further, the selectivity, yield and product purity achieved by the composite catalyst are substantially the same after the catalyst is used for 5 cycles, which shows that the catalytic effect of the composite catalyst is more stable.

The present disclosure provides a catalyst with a symmetrical structure in use for catalyzing a reaction of an epoxide compound and carbon dioxide, and the catalyst has the general structural formula (1). The catalyst can catalyze the addition reaction of carbon dioxide and the epoxide compound under environmentally friendly and mild conditions. Through researches, it is found that the compound of formula (1) is able to overcome the problems of low catalytic performance, long reaction time, strong toxicity and the like existed in the reaction process of the existing catalyst for catalyzing the reaction of carbon dioxide and the epoxide compound. In addition, the present catalyst has less complex reaction sites, so that it can effectively reduce the side reactions in catalyzing the addition reaction of carbon dioxide and the epoxide compound, thus improving the final product purity and reducing the impurity species. Further, it is found in the present disclosure that the catalytic mechanism of the compound of formula (2) is similar to that of the compound of formula (1), but it has a stronger adsorption to the oxygen free radicals formed from the epoxides (in which the ring of the epoxide is opened and is further reacted with halogen). When the compound of formula (1) is compounded with a small amount of the compound of formula (2), the above-mentioned oxygen free radicals can be transferred, and the compound of formula (1) can be released, thus reducing decomposition caused by nucleophilic adsorption. When the compound of formula (1) and the compound of formula (2) are used as the composite catalyst in a proper proportion, the stability of the catalyst used for cycles can be improved, and a good catalytic activity can still be maintained after a plurality of cycles.

To sum up, in the present disclosure, the compound of formula (1) is used as the catalyst to catalyze the reaction of carbon dioxide and the epoxide compound under environmentally friendly and mild conditions, and the obtained product has higher purity and fewer impurity species. Further, when the compound of formula (1) and the compound of formula (2) are used as the composite catalyst, the catalytic stability is significantly improved. and the good catalytic activity can be maintained after a plurality of cycles.

Technical features of the above-mentioned embodiments can be combined in any combination, and in order to make the description concise, not all the possible combinations of the technical features of the above-mentioned embodiments are described herein. However, as long as there is no contradiction between the technical features in the combination, the features can be combined and should be considered as being in the scope of the present description.

The embodiments described above are merely representative of several embodiments of the present disclosure and are described in detail, but are not to be construed as limiting the scope of the present disclosure. It is to be noted that those person skilled in the art could further make several variations and modifications without departing from the concept of the present disclosure, which are within the scope of the present disclosure. Accordingly, the protection scope of the present disclosure is as set forth in the appending claims.

Claims

1. A method for catalyzing a reaction of an epoxide compound and carbon dioxide with a catalyst, wherein the catalyst comprises at least one compound of formula (1):

2. The method of claim 1, wherein R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15 carbon atoms; and/or, X is selected from F, Cl, Br, or I.

3. The method of claim 2, wherein R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 10 carbon atoms.

4. The method of claim 2, wherein X is selected from Br or Cl.

5. The method of claim 1, wherein the compound of formula (1) comprises at least one of:

6. The method of claim 1, wherein the catalyst further comprises at least one compound of formula (2):

7. The method of claim 6, wherein R1 is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15 carbon atoms; and/or, Y is selected from F, Cl, Br, or I.

8. The method of claim 7, wherein R1 is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 10 carbon atoms.

9. The method of claim 7, wherein Y is selected from Br or Cl.

10. The method of claim 6, wherein the compound of formula (2) comprises at least one of:

11. The method of claim 6, wherein a molar ratio of the compound of formula (1) to the compound of formula (2) is in a range of 100:(1 to 12).

12. The method of claim 1, wherein the epoxide compound is selected from at least one compound of formula (3):

13. The method of claim 1, wherein a molar ratio of the catalyst to the epoxide compound is in a range of (0.5×10−3 to 1.5×10−2):1.

14. The method of claim 1, wherein the reaction is performed at a temperature of 100 to 200° C., and/or under a pressure of 1 to 5 MPa.

15. A catalyst comprising at least one compound of formula (1) and at least one compound of formula (2):

16. The catalyst of claim 15, wherein R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15 carbon atoms; and/or, X is selected from F, Cl, Br, or I.

17. The catalyst of claim 15, wherein R1 is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 15 carbon atoms; and/or, Y is selected from F, Cl, Br, or I.

18. The catalyst of claim 15, wherein: R is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 10 carbon atoms;X is selected from Br or CI;R1 is selected from the alkyl group, the alkenyl group, or the halohydrocarbyl group, and has 1 to 10 carbon atoms; and/orY is selected from Br or CL.

19. The catalyst of claim 15, wherein the compound of formula (1) comprises at least one of:

20. The catalyst of claim 15, wherein the compound of formula (2) comprises at least one of: