Trinitrogen ligand catalyst, preparation method and application of trinitrogen ligand catalyst in synthesis of cyclic carbonate substances

Abstract

The invention belongs to the technical field of organic synthesis, and particularly relates to a tri-nitrogen ligand catalyst, a preparation method and application of the tri-nitrogen ligand catalyst in synthesis of cyclic carbonate substances. The trinitrogen ligand catalyst provided by the invention is specifically obtained by reacting a trinitrogen amine compound with a specific structure with a metal salt, the prepared trinitrogen ligand catalyst shows good catalytic efficiency in the process of cyclizing and synthesizing cyclic carbonate from carbon dioxide, the highest yield of the product can reach 99%, and moreover, the yield of the product can reach 99%. The catalyst provided by the invention also has the advantages of mild reaction conditions, no need of noble metal as an active center for coordination, low cost and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic synthesis, and particularly relates to a triazene ligand catalyst, a preparation method and application thereof in synthesis of cyclic carbonate substances. BACKGROUND

[0002] Carbon dioxide is a kind of rich, non-toxic and renewable carbon raw material, and its utilization and conversion can not only effectively solve environmental problems and alleviate the greenhouse effect, but also promote the sustainable development of economy and solve the problem of energy shortage.

[0003] Cyclic carbonate is a kind of compound with low toxicity, low volatility, non-flammability, good biocompatibility and biodegradability, and is widely used as fuel additive, polar aprotic solvent, electrolyte in lithium ion battery, intermediate of pharmaceutical or fine chemical, and monomer of polycarbonate and polyurethane.

[0004] At present, the catalytic conversion of carbon dioxide into high value-added chemicals, especially cyclic carbonate products, has become an important way for carbon dioxide resource utilization.

[0005] However, in the process of converting carbon dioxide into cyclic carbonate, the complexes of some catalytic systems must use noble metals as catalytic active centers, resulting in high cost of catalytic reaction. In addition, the catalytic system also has problems such as low yield, poor selectivity, need to add a catalyst, harsh reaction conditions, and the like. The catalyst has become a bottleneck problem restricting the application of the above method. SUMMARY

[0006] In order to solve the problems of low catalytic activity, low yield, poor selectivity, need to add a catalyst, harsh reaction conditions and high cost of catalyst caused by the presence of noble metals in the process of converting CO2 into cyclic carbonate substances, the present application provides a single-component catalyst which is non-noble metal, mild, efficient and highly selective. In addition, the prepared catalyst also has the advantages of mild reaction conditions, environmental protection and low cost in the process of catalytic synthesis of cyclic carbonate substances.

[0007] The first aspect to be protected by the present application is to provide a triazene ligand catalyst, which is obtained by coordination of a triazene ligand comprising the following structure with a metal salt: ; wherein R 1 is independently selected from any one of N,N'-dimethyl, fluorine, chlorine, bromine, iodine, alkyl, aryl, alkoxy, amino and hydrogen; R 2 is independently selected from any one of alkyl, aryl, alkoxy and hydrogen; The structural formula of the metal salt is MX n : Wherein, M is selected from any one of iron, nickel, cobalt, aluminum, magnesium, zinc; X is fluoride, chloride, bromide, iodide ion, and n=2 or 3.

[0008] In the above-mentioned triazene ligand catalyst, preferably, the molar ratio of the triazene ligand to the metal salt is 1-4:1.

[0009] More preferably, the molar ratio of the triazene ligand to the metal salt is 1-1.5:1.

[0010] The second aspect to be protected by the present application is the application of the triazene ligand catalyst with the above structure in the synthesis of cyclic carbonate substances.

[0011] Further, the application is to use an epoxy compound and CO2 as raw materials, and under the action of the catalyst, a cyclic carbonate substance is generated by reaction.

[0012] Preferably, the cyclic carbonate substance has the following structural formula: ; Wherein, R 1 Is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, halogenated alkyl, aryl (including substituted aryl), phenoxyalkyl, hydrogen; R 2 Is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, halogenated alkyl, aryl (including substituted aryl), phenoxyalkyl, hydrogen.

[0013] The third aspect to be protected by the present application is to provide a preparation method of a cyclic carbonate substance, specifically to use an epoxy compound and CO2 as raw materials, and under the action of the triazene ligand catalyst, a cyclic carbonate substance is generated by reaction, and the reaction equation of the method is as follows: ; During the reaction, the pressure of CO2 is 0.1-2.5 Mpa; the molar percentage of the catalyst in the epoxy compound is 0.1%-10%; The structural formula of the epoxy compound is: ; Wherein, R 1 Is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, halogenated alkyl, aryl (including substituted aryl), phenoxyalkyl, hydrogen; R 2any one independently selected from the group consisting of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, haloalkyl, aryl (including substituted aryl), phenoxyalkyl, hydrogen.

[0014] Preferably, the CO2 pressure is 0.1-0.5 MPa; the catalyst accounts for 0.2%-2.5% of the molar percentage of the epoxide compound in the preparation method of the cyclic carbonate substance provided by the application. Preferably, no reaction solvent is added during the reaction; or acetonitrile is added as the reaction solvent, the reaction temperature is 25-140 ℃, and the reaction time is 2-24 h.

[0015] Further preferably, acetonitrile is added as the reaction solvent, the reaction temperature is 70-90 ℃, and the reaction time is 6-8 h.

[0016] Further preferably, after the preparation reaction of the cyclic carbonate substance is completed, the obtained cyclic carbonate is purified, and the specific operation is as follows: the mixture obtained after the reaction is cooled to room temperature, then the mixture is transferred to a flask, silica gel is added, and the mixture is further purified through a silica gel column, and then the purified cyclic carbonate substance is obtained through vacuum distillation.

[0017] Preferably, when the silica gel column is used for purification, the eluent is a mixture of petroleum ether and ethyl acetate, and the volume ratio of petroleum ether to ethyl acetate is 3-6:1.

[0018] The application has the following beneficial effects: (1) The catalyst provided by the application itself can act as a nucleophile to promote the ring opening of the epoxide, and the catalyst system is a single-component catalyst system, without the need for additional additives, thereby avoiding the addition of other additives during the reaction and facilitating the purification of the product. (2) The application provides a new method for the fixation and conversion of CO2 and the preparation of cyclic carbonate substances, and the catalyst provided by the application exhibits good reaction selectivity in the process of catalyzing the reaction of CO2 to generate cyclic carbonate products, and has mild reaction conditions, high reaction activity, and high product yield. Experimental results show that the product yield is as high as about 99%. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The nuclear magnetic resonance hydrogen spectrum of the product in Example 1 of the application; Figure 2 The nuclear magnetic resonance carbon spectrum of the product in Example 1 of the application; Figure 3 The nuclear magnetic resonance hydrogen spectrum of the product in Example 2 of the application; Figure 4 The nuclear magnetic resonance carbon spectrum of the product in Example 2 of the application; Figure 5 NMR hydrogen spectrum of the product in Example 3 of the present application; Figure 6 NMR carbon spectrum of the product in Example 3 of the present application; Figure 7 NMR hydrogen spectrum of the product in Example 4 of the present application; Figure 8 NMR carbon spectrum of the product in Example 4 of the present application; Figure 9 NMR hydrogen spectrum of the product in Example 5 of the present application; Figure 10 NMR carbon spectrum of the product in Example 5 of the present application. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the present application, the present application will be further described in conjunction with specific embodiments.

[0021] The pharmaceuticals involved in the present application are purchased from Shanghai Maikelin Biochemical Technology Co., Ltd., Shanghai Annaiji Chemical Co., Ltd., Beijing Bailingwei Technology Co., Ltd., Shanghai Aladdin Biochem Technology Co., Ltd., and Tianjin Kaition Chemical Reagent Co., Ltd.

[0022] Yield calculation method: yield = actual yield / theoretical yield x 100%, and the yield calculation refers to GB / T 27417-2017.

[0023] Example 1 A method for preparing cyclic carbonates by using epichlorohydrin and CO2 as raw materials, comprising the following steps: (1) 1 mmol of epichlorohydrin and a catalyst (2.5% mmol of epichlorohydrin) were sequentially added into a reaction tube and then into a 25 mL reaction kettle equipped with a magnetic stirrer, respectively; The specific preparation method of the catalyst is as follows: under normal temperature and pressure conditions, 1.1 mmol of dimethylpyridine amine was weighed and dissolved in acetonitrile, and 1 mmol of cobalt iodide was added to generate a large amount of solid. After 1 h of reaction, plate detection was performed, and after the reaction was completed, the dry complex was obtained by centrifugation and washing with acetonitrile three times, which was the catalyst; (2) The reaction kettle was purged with CO2 and filled with 0.5 MPa of CO2, and the reaction was carried out at 80°C for 6 h to obtain a mixed liquid containing the product; (3) After the reaction was completed, the mixed liquid obtained in (2) was transferred to a flask, 100-200 mesh silica gel was added, and further purification was carried out by silica gel column chromatography (petroleum ether: ethyl acetate = 5:1). After removing the solvent by reduced pressure distillation, a colorless liquid product was obtained, which was a cyclic carbonate product.

[0024] Figure 2 shows the1H NMR spectrum of the target product, and Figure 3 shows the13C NMR spectrum of the target product, for verifying the structure and purity of the cyclic carbonate material. Figure 1 Figure 2 Figure 2 shows the1H NMR spectrum of the target product, and Figure 3 shows the13C NMR spectrum of the target product, for verifying the structure and purity of the cyclic carbonate material.

[0025] The experimental results show that the yield of the obtained product is 92%.

[0026] 1 H NMR (400 MHz, Chloroform- d ) δ 5.03 (dtd, J = 8.7, 5.3, 3.5 Hz, 1H), 4.62 (t, J = 8.6 Hz, 1H), 4.43 (dd, J = 8.9, 5.7 Hz, 1H), 3.90-3.68 (m, 2H).

[0027] 13 C NMR (101 MHz, Chloroform- d ) δ 154.49, 74.45, 67.00, 44.06.

[0028] Example 2 A method for preparing a cyclic carbonate material using allyl glycidyl ether and CO2 as raw materials, comprising the following steps: (1) 1 mmol of allyl glycidyl ether and a catalyst (2.5% mmol) are sequentially added into a reaction tube, which is placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is obtained by reacting dimethylpyridine amine with cobalt iodide at a molar ratio of 1.1:1; the preparation method is the same as that of Example 1, and the preparation method of the catalyst in the following examples is the same as that of Example 1 unless otherwise specified; (2)-(3) are the same as Example 1.

[0029] Figure 2 shows the1H NMR spectrum of the target product, and Figure 3 shows the13C NMR spectrum of the target product, for verifying the structure and purity of the cyclic carbonate material. Figure 3 Figure 4 Figure 2 shows the1H NMR spectrum of the target product, and Figure 3 shows the13C NMR spectrum of the target product, for verifying the structure and purity of the cyclic carbonate material.

[0030] The experimental results show that the yield of the obtained product is 99%.

[0031] 1 H NMR (400 MHz, Chloroform- d ) δ 5.88 (ddt, J ​​= 16.4, 10.9, 5.6 Hz,1H), 5.26 (dd, J = 25.8, 13.8 Hz, 2H), 4.85 (tdd, J = 9.2, 4.2, 2.3 Hz, 1H), 4.52(td, J = 8.4, 1.4 Hz, 1H), 4.42 (dd, J = 8.3, 6.3 Hz, 1H), 4.15- 3.99 (m, 2H),3.79-3.55 (m, 2H)。

[0032] 13 C NMR (101 MHz, Chloroform- d ) δ 155.06, 133.67, 117.94, 117.92,75.12, 72.55, 68.81, 66.28。

[0033] Example 3 A method for preparing cyclic carbonate using butyl glycidyl ether and CO2 as raw materials, comprising the following steps: (1) 1 mmol of butyl glycidyl ether and a catalyst (2.5% mmol) were sequentially added into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with cobalt iodide at a molar ratio of 1.1:1; (2)-(3) are the same as example 1.

[0034] The Figure 5 , and Figure 6 are the hydrogen spectrum and carbon spectrum of the target product, respectively, which are used to verify the structure and purity of the cyclic carbonate.

[0035] The experimental results show that the yield of the obtained product is 98%.

[0036] 1 H NMR (400 MHz, Chloroform- d ) δ 4.82 (dtd, J = 9.2, 4.9, 4.3, 2.4 Hz,1H), 4.51 (td, J = 8.3, 1.3 Hz, 1H), 4.40 (ddd, J= 8.1, 6.1, 1.3 Hz, 1H), 3.77-3.56 (m, 2H), 3.51 (t, J = 6.5 Hz, 2H), 1.61-1.48 (m, 2H), 1.36 (h, J = 7.4 Hz, 2H), 0.98-0.83 (m, 3H).

[0037] 13 C NMR (101 MHz, Chloroform- d ) δ 75.14, 71.86, 69.59, 66.31, 31.50,19.15, 13.87.

[0038] Example 4 A method for preparing cyclic carbonates using styrene oxide and CO2 as raw materials specifically includes the following steps: (1) Add 1 mmol of styrene oxide and 2.5% mmol of catalyst to the reaction tubes in sequence, and then place them into 25 mL Schlenk flasks equipped with magnetic stirrers. The catalyst is a complex obtained by reacting dimethylpyridinium amine with cobalt iodide in a molar ratio of 1.1:1. (2)-(3) Same as Example 1.

[0039] Appendix Figure 7 Appendix Figure 8 The images show the proton and carbon NMR spectra of the target product, respectively, to verify the structure and purity of the cyclic carbonates.

[0040] The experimental results showed that the yield of the obtained product was 99%.

[0041] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0042] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25, 126.01, 78.10, 71.26.

[0043] Example 5 A method for preparing cyclic carbonate using 1,2-epoxypropane and CO2 as raw materials, comprising the following steps: (1) 1 mmol of 1,2-epoxypropane, dimethylpyridine amine and the complex (2.5% mmol) obtained by reacting 1.1:1 of cobalt iodide were sequentially added into a glass tube, and then sequentially placed into a 25 mL Schlenk flask equipped with a magnetic stirrer; (2)-(3) The same as Example 1.

[0044] Appendix Figure 9 , Appendix Figure 10 are the hydrogen spectrum and carbon spectrum of the target product respectively, which are used to verify the structure and purity of the cyclic carbonate.

[0045] The experimental results show that the yield of the obtained product is 92%.

[0046] 1 H NMR (400 MHz, Chloroform- d ) δ 4.90 (tt, J = 13.4, 4.7 Hz, 1H), 4.59(t, J = 8.1 Hz, 1H), 4.06 (dd, J = 8.5, 7.2 Hz, 1H), 1.50 (d, J = 6.4 Hz, 3H).

[0047] 13 C NMR (101 MHz, Chloroform- d ) δ 155.22, 73.76, 70.74, 19.28.

[0048] Example 6 A method for preparing cyclic carbonate using epoxystyrene and CO2 as raw materials, comprising the following steps: (1) 1 mmol of epoxystyrene, N1-(2-(dimethylamino)ethyl)-N1,N2,N2-trimethylethane-1,2-diamine and the complex (2.5% mmol) obtained by reacting 1.1:1 of cobalt iodide were sequentially added into a glass tube, and then sequentially placed into a reaction kettle equipped with a magnetic stirrer; (2)-(3) The same as Example 1.

[0049] The experimental results show that the yield of the obtained product is 89%.

[0050] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51 – 7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0051] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26。

[0052] Example 7 A method for preparing cyclic carbonate using epoxystyrene and CO2 as raw materials, comprising the following steps: (1) 1 mmol of epoxystyrene, 3-(4-methylpiperazin-1-yl)prop-1-amine ligand and 1:1 complex of nickel bromide (2.5% mmol) obtained by reaction were sequentially added into a glass tube, and then placed in a reaction kettle equipped with a magnet; (2)-(3) The same as example 1.

[0053] The experimental results show that the yield of the obtained product is 88%.

[0054] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51 – 7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0055] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26。

[0056] Example 8 A method for preparing cyclic carbonate using epoxystyrene and CO2 as raw materials, comprising the following steps: (1) 1 mmol of styrene oxide, 2-(4-methylpiperazin-l-yl)ethan-l-amine and 1.1:1 complex (2.5% mmol) of cobalt iodide obtained by reacting dimethylpyridine amine with zinc iodide were sequentially added into a glass tube, which was then placed in a reaction kettle equipped with a magnet; (2)-(3) Same as Example 1.

[0057] The experimental results show that the yield of the obtained product is 92%.

[0058] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51 - 7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0059] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25, 126.01, 78.10, 71.26.

[0060] Example 9 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, specifically comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) were sequentially added into a reaction tube, which was then placed in a 25 mL Schlenk bottle equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with zinc iodide at a molar ratio of 1.1:1; (2)-(3) Same as Example 1.

[0061] The experimental results show that the yield of the obtained product is 86%.

[0062] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0063] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0064] Example 10 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) are sequentially added into a reaction tube, which is placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with cobalt bromide at a molar ratio of 1.1:1; (2)-(3) are the same as Example 1.

[0065] The experimental results show that the yield of the obtained product is 93%.

[0066] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0067] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0068] Example 11 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) are sequentially added into a reaction tube, which is placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with cobalt bromide at a molar ratio of 1.1:1; (2)-(3) are the same as Example 1.

[0069] The experimental results show that the yield of the obtained product is 85%.

[0070] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0071] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26。

[0072] Example 12 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) are sequentially added into a reaction tube, which is placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with ferrous chloride at a molar ratio of 1.1:1; (2)-(3) are the same as in Example 1.

[0073] The experimental results show that the yield of the obtained product is 76%.

[0074] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0075] 13 C NMR (101 MHz, Chloroform- d) δ 155.03, 135.87, 129.75, 129.25, 126.01, 78.10, 71.26.

[0076] Example 13 A method for preparing cyclic carbonates using styrene oxide and CO2 as raw materials includes the following steps: (1) Add 1 mmol of styrene oxide and 2.5% mmol of catalyst to the reaction tubes in sequence, and then place them into 25 mL Schlenk flasks equipped with magnetic stirrers. The catalyst is a complex obtained by reacting dimethylpyridinium chloride with ferrous bromide in a molar ratio of 1.1:1. (2)-(3) Same as Example 1.

[0077] The experimental results showed that the yield of the obtained product was 92%.

[0078] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0079] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25, 126.01, 78.10, 71.26.

[0080] Example 14 A method for preparing cyclic carbonates using styrene oxide and CO2 as raw materials: (1) Add 1 mmol of styrene oxide and 2.5% mmol of catalyst to the reaction tubes in sequence, and then place them into 25 mL Schlenk flasks equipped with magnetic stirrers. The catalyst is a complex obtained by reacting dimethylpyridinium chloride with ferric bromide in a molar ratio of 1.1:1. (2)-(3) Same as Example 1.

[0081] The experimental results showed that the yield of the obtained product was 92%.

[0082] 1H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0083] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0084] Example 15 The method for preparing cyclic carbonate with styrene oxide and CO2 as raw materials specifically comprises the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) are sequentially added into a reaction tube, which is placed in a 25 mL Schlenk bottle equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with zinc chloride at a molar ratio of 1.1:1; (2)-(3) are the same as in Example 1.

[0085] The experimental results show that the yield of the obtained product is 86%.

[0086] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0087] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0088] Example 16 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, specifically comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) were sequentially added into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with zinc bromide at a molar ratio of 1.1:1; (2)-(3) are the same as in Example 1.

[0089] The experimental results show that the yield of the obtained product is 86%.

[0090] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0091] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0092] Example 17 A method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials, specifically comprising the following steps: (1) 1 mmol of styrene oxide and a catalyst (2.5% mmol) were sequentially added into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; The catalyst is a complex obtained by reacting dimethylpyridine amine with zinc iodide at a molar ratio of 1.1:1; (2)-(3) are the same as in Example 1.

[0093] The experimental results show that the yield of the obtained product is 86%.

[0094] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J= 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0095] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0096] Example 18 Method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials: (1) 1 mmol of styrene oxide and catalyst (5% mmol) were sequentially added into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer, respectively; The catalyst was a complex obtained by reacting dimethylpyridine amine with cobalt iodide at a molar ratio of 1.1:1; (2)-(3) The same as Example 1.

[0097] The experimental results show that the yield of the obtained product is 99%.

[0098] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H)。

[0099] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0100] Example 19 Method for preparing cyclic carbonate using styrene oxide and CO2 as raw materials: (1) 1 mmol of styrene oxide and catalyst (2% mmol) were sequentially added into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer, respectively; wherein the catalyst is a complex obtained from the reaction of [2- (dimethylamino) ethyl] piperazine with cobalt iodide in a molar ratio of 1.1 : 1 ; (2) - (3) same as example 1.

[0101] The experimental results show that the yield of the product obtained is 99%.

[0102] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0103] 13 C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25, 126.01, 78.10, 71.26.

[0104] Example 20 Process for the preparation of cyclic carbonates from styrene oxide and CO2: (1) 1 mmol of styrene oxide and catalyst (5% mmol) were successively introduced into a reaction tube, which was placed in a 25 mL Schlenk flask equipped with a magnetic stirrer; wherein the catalyst is a complex obtained from the reaction of 3,3'-iminobis- N,N (dimethylpropylamine) with cobalt iodide in a molar ratio of 1.1 : 1 ; (2) - (3) same as example 1.

[0105] The experimental results show that the yield of the product obtained is 93%.

[0106] 1 H NMR (400 MHz, Chloroform- d ) δ 7.51-7.29 (m, 5H), 5.67 (t, J = 8.0Hz, 1H), 4.79 (t, J = 8.4 Hz, 1H), 4.32 (t, J = 8.2 Hz, 1H).

[0107] 13C NMR (101 MHz, Chloroform- d ) δ 155.03, 135.87, 129.75, 129.25,126.01, 78.10, 71.26.

[0108] From the above embodiments of the present application, it can be seen that the catalyst prepared by the method of the present application can be used to catalyze the production of cyclic carbonate substances, and high yield of cyclic carbonates can be obtained, up to 99%, and the catalytic system in the present application has high activity and the reaction conditions are more mild.

[0109] The substantial features and significant effects of the present application can be embodied from the above embodiments, but the above embodiments cannot limit the present application in any way, and some non-essential improvements and adjustments made by those skilled in the art according to the content of the present application all belong to the protection scope of the present application.

Claims

1. A trinitrogen ligand catalyst, characterized in that, The trinitrogen ligand catalyst is obtained by coordination of a trinitrogen ligand comprising the following structure with a metal salt: ； Among them, R 1 It is independently selected from any one of N,N'-dimethyl, fluorine, chlorine, bromine, iodine, alkyl, aryl, alkoxy, amino or hydrogen; R 2 Independently selected from any one of alkyl, aryl, alkoxy, or hydrogen; The metal salt has the structural formula MX. n : M is selected from any one of iron, nickel, cobalt, aluminum, magnesium, and zinc; X represents fluorine, chloride, bromide, or iodide ions, and n = 2 or 3.

2. The trinitrogen ligand catalyst as described in claim 1, characterized in that, The molar ratio of the trinitrogen ligand to the metal salt is 1 to 4:

1.

3. The application of the trinitrogen ligand catalyst as described in claim 1 in the synthesis of cyclic carbonates, characterized in that, Using epoxides and CO2 as raw materials, cyclic carbonates are generated under the action of the trinitrogen ligand catalyst described in claim 1.

4. The application as described in claim 3, characterized in that, The cyclic carbonate material described above has the following structural formula: ； Among them, R 1 It is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, haloalkyl, aryl (including substituted aryl), phenoxyalkyl or hydrogen; R 2 It is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, haloalkyl, aryl (including substituted aryl), phenoxyalkyl or hydrogen.

5. A method for preparing cyclic carbonates, characterized in that, Using epoxides and CO2 as raw materials, a reaction is carried out under the action of the catalyst described in claim 1 to generate cyclic carbonates. During the reaction, the CO2 pressure is 0.1~2.5 MPa; the catalyst accounts for 0.1%~10% of the molar percentage of the epoxide compound; The structural formula of the epoxy compound is: ； Among them, R 1 It is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, haloalkyl, aryl (including substituted aryl), phenoxyalkyl or hydrogen; R 2 It is independently selected from any one of propargyloxymethyl, allyloxymethyl, alkyl, alkoxyalkyl, haloalkyl, aryl (including substituted aryl), phenoxyalkyl or hydrogen.

6. The method for preparing cyclic carbonates as described in claim 5, characterized in that, During the reaction, the pressure of the CO2 is 0.1~0.5 MPa; the catalyst accounts for 0.2%~2.5% of the molar percentage of the epoxide compound.

7. The method for preparing cyclic carbonates as described in claim 5, characterized in that, During the reaction, no reaction solvent is used; or, acetonitrile is added as the reaction solvent, the reaction temperature is 25~140℃, and the reaction time is 2~24 h.

8. The method for preparing cyclic carbonates as described in claim 5, characterized in that, After the reaction is complete, the cyclic carbonates are purified. The specific procedure is as follows: take the mixture obtained after the reaction, cool it to room temperature, then transfer the mixture to a round-bottom flask, add silica gel, further purify it through a silica gel column, and then distill it under reduced pressure to obtain the purified cyclic carbonates.

9. The method for preparing cyclic carbonates as described in claim 8, characterized in that, When using silica gel column purification, the eluent is a mixture of petroleum ether and ethyl acetate, with a volume ratio of petroleum ether to ethyl acetate of 3~6:1.

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