Synthesis method of beta-phenoxy carboxylic acid ethyl ester compound

Abstract

The invention aims to provide a synthesis method for preparing a beta-phenoxy carboxylic acid ethyl ester compound by taking an ethylene oxide compound and a carboxylic acid aryl ester compound as raw materials, activating a C-O bond under the catalysis of potassium iodide and under the combined action of alkali and a solvent. In the reaction, the yields of various substrates are high, corresponding products can be obtained from substrates modified by alkyl, halogen, ester groups, trifluoromethyl and other groups, and the reaction has good functional group tolerance. Under mild reaction conditions, substituent groups such as electron donating groups, electron withdrawing groups, halogen groups and the like on benzene rings, naphthalene rings and biphenyl can be used for obtaining corresponding products with excellent yield in the reaction. The synthesis route can avoid the use of transition metal, does not need high temperature, and is mild in reaction and environment-friendly.

Description

Technical field

[0001] The invention belongs to the field of organic synthesis, and particularly relates to a method for synthesizing beta-phenoxycarboxylic acid ethyl ester compounds. [Background Technology]

[0002] Ethylene oxide compounds are very important C2 synthons, with broad applications in the synthesis of pesticides, pharmaceutical intermediates, and materials science. In intermediate synthesis, ethylene oxide compounds can be used to synthesize various fine chemicals by activating carbon-oxygen (CO) bonds. In terms of materials, ethylene oxide compounds are important raw materials for the construction of polyesters, polyethers, and epoxy resins.

[0003] Due to the influence of their ring strain and other factors, ethylene oxide compounds have extremely active chemical properties. They can selectively open the ring and react with nucleophiles under acidic or alkaline conditions. They show very important application value in the synthesis of five-membered and six-membered oxygen-containing heterocycles and the construction of carbon-carbon bonds and carbon-hetero bonds.

[0004] Reactions involving oxiranes can be broadly categorized into two types: one involves the synthesis of oxygen-containing heterocyclic compounds through ring-opening and recyclization, and the other involves the synthesis of chain compounds through ring-opening coupling. Epoxide reactions involve the first step of ring-opening the oxirane moiety. Based on the site of the ring-opening reaction, there are two methods for the ring-opening of epoxides: one is under alkaline conditions, where the nucleophile forms a coordination bond with the oxygen atom, promoting the attack of the nucleophile on the carbon atom with fewer substituents, leading to the ring-opening of the epoxide; the other is under acidic conditions, where the nucleophile preferentially attacks the carbon atom with a higher positive charge (generally, the carbon atom with more substituents), leading to the ring-opening of the epoxide.

[0005] Current research on reactions involving oxiranes has involved a variety of classical couplings and carbon heteroatom construction. Oxiranes can promote the ring-opening of oxiranes under alkaline or acidic conditions, or in the presence of organic and metal catalysts. They are essential building blocks for the construction of esters, amides, carboxylic acids, alcohols, carbonyl groups, and five- and six-membered oxygen-containing heterocycles.

[0006] However, research on reactions involving oxiranes still needs improvement: While a wide range of coupling reagents are available for the ring-opening coupling reactions of oxiranes, few studies have reported reactions with ester groups. For example, compounds such as aryl carboxylates are widely present in nature. Developing ring-opening coupling reactions between oxiranes and aryl carboxylates is crucial for synthesizing structurally diverse compounds. To date, such reactions require transition metal catalysis or high temperatures. Therefore, developing a transition metal-free coupling reaction between oxiranes and aryl carboxylates under mild conditions is of interest.

[0007] To address the shortcomings of the aforementioned methods, we have developed a potassium iodide-catalyzed method for the synthesis of β-phenoxycarboxylic acid ethyl esters from carboxylic acid aryl esters and oxiranes. Potassium iodide promotes the activation of the CO bond in the ester group, while cesium carbonate and the polar solvent N,N-dimethylacetamide facilitate the ring-opening of the oxiranes, thereby constructing the ester group and alkyl aryl ether. Under mild reaction conditions, this reaction can yield the corresponding products in good yields even with electron-donating, electron-withdrawing, and halogen substituents on the benzene ring, as well as with naphthalene and biphenyl. [Summary of the invention]

[0008] The object of the present invention is to provide a synthesis method for preparing β-phenoxycarboxylic acid ethyl ester compound by using oxirane compound and carboxylic acid aryl ester compound as raw materials, activating CO bond under potassium iodide catalysis, and the combined action of base and solvent.

[0009] In order to achieve the above-mentioned object of the invention, the present invention proposes the following technical solutions:

[0010] A method for synthesizing a β-phenoxycarboxylic acid ethyl ester compound, wherein the structure of the β-phenoxycarboxylic acid ethyl ester compound is shown in Formula I:

[0011]

[0012] Wherein R1 includes but is not limited to one selected from the group consisting of methyl, phenyl, 4-methylphenyl, 4-methoxyphenyl, and 4-chlorophenyl. R2 includes but is not limited to one selected from the group consisting of phenyl, 2-methylphenyl, 3-fluorophenyl, 2-acetoxyphenyl, 4-trifluoromethylphenyl, 1-naphthyl, and 4-biphenylyl.

[0013] The synthesis method of Compound I is characterized in that phenyl benzoate, styrene oxide, potassium iodide, cesium carbonate, and dimethylacetamide solvent are placed in a reaction vessel, mixed, and stirred and heated at 70°C under a nitrogen atmosphere for 20 hours. After the reaction is completed, the dimethylacetamide solvent is removed by vacuum distillation and the crude product is separated by column chromatography to obtain the β-phenoxycarboxylic acid ethyl ester compound represented by Formula I.

[0014] In the synthesis method, the structure of the raw material ethylene oxide compound is shown in Formula II:

[0015]

[0016] Wherein R3 includes but is not limited to one of methyl, 1,1-dimethyl, ethyl, n-butyl, n-butyl, tert-butoxymethyl, allyloxymethyl, (2-methylphenoxy)methyl, (benzyloxy)methyl, and [(furan-2-yl)methoxy]methyl.

[0017] In the synthesis method, the catalyst is selected from at least one of cuprous iodide, copper oxide, bistriphenylphosphine nickel bromide, lithium iodide, lithium bromide, sodium bromide, nickel bromide, and potassium iodide.

[0018] In the synthesis method, the organic solvent is selected from at least one of acetonitrile, N-methylpyrrolidone, dimethylformamide, and dimethylacetamide.

[0019] In the synthesis method, the base is selected from at least one of potassium carbonate, potassium bicarbonate, potassium acetate, potassium methoxide, potassium tert-butoxide, sodium carbonate, sodium methoxide, sodium acetate, cesium acetate, triethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene, and cesium carbonate.

[0020] In the synthesis method, the inert gas is selected from at least one of nitrogen, argon and helium.

[0021] In the synthesis method, the preparation method further comprises: after the reaction is completed, cooling the reaction system to room temperature, and performing reduced pressure distillation to obtain the product.

[0022] Provided is a synthesis method for preparing β-phenoxycarboxylic acid ethyl ester compounds by using ethylene oxide compounds as raw materials and continuously adding base and solvent under the condition of activation of CO bond by potassium iodide catalysis.

[0023] Based on experimental results, the present invention provides a method for preparing β-phenoxycarboxylic acid ethyl ester compounds using oxirane compounds as raw materials and subsequently adding a base and a solvent under conditions where potassium iodide catalyzes the activation of the CO bond. This reaction produces high yields for various substrates, and substrates modified with groups such as alkyl, halogen, ester, and trifluoromethyl groups can all yield corresponding products, with good functional group tolerance. Under mild reaction conditions, the reaction can produce corresponding products in excellent yields from benzene rings containing electron-donating, electron-withdrawing, and halogen substituents, as well as naphthalene rings and biphenyl. This synthetic route avoids the use of transition metals, does not require high temperatures, and offers a mild reaction and environmentally friendly properties.

Brief Description of the Drawings

[0024] Attachment Figure 1 Shown is a synthetic route diagram of the β-phenoxycarboxylic acid ethyl ester compounds provided by the present invention. [Specific implementation method]

[0025] The synthesis method of the present invention is further described below in conjunction with the synthesis examples of the present invention:

[0026] like Figure 1The present invention provides a synthesis process for a β-phenoxycarboxylic acid ethyl ester compound, comprising the following steps: placing a carboxylic acid aryl ester compound, an ethylene oxide compound (120% by mole based on the carboxylic acid compound), potassium iodide (8% by mole based on the carboxylic acid compound), cesium carbonate (60% by mole based on the carboxylic acid compound), and N,N-dimethylacetamide in a reaction vessel, mixing the mixture, and stirring the mixture at 70°C under a nitrogen atmosphere for 20 hours. The N,N-dimethylacetamide solvent is removed by distillation under reduced pressure, and the crude product is separated by column chromatography to obtain the target product.

[0027] The present invention will be further described below with reference to specific preparation examples:

[0028] Synthesis example 1

[0029] Synthesis of 1-phenyl-2-phenoxyethyl benzoate

[0030] To a reactor, add 0.200 mmol of phenyl benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir the reaction at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 79% yield. 1 HNMR (400MHz, CDCl3) δ8.10(d,J=1.2Hz,1H),8.08(d,J=1.2Hz,1H),7.57-7.49(m,3H),7.45-7.33(m,5H),7.28-7.23( m,2H),6.97-6.89(m,3H),6.38(dd,J=8.0,4.0Hz,1H),4.42(dd,J=10.4,7.6Hz,1H),4.28(dd,J=10.4,7.6Hz,1H)ppm. 13 C NMR (100MHz, CDCl3) δ165.7,158.5,137.2,133.1,130.0,129.8,129.5,128.6,128.5,128.4,126.7,121.2,114.8,74.6,70.5ppm.

[0031] Synthesis example 2

[0032] Synthesis of 1-phenyl-2-phenoxyethyl p-methylbenzoate

[0033] To a reactor, add 0.200 mmol of phenyl p-toluate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 67% yield. 1 H NMR (400MHz, CDCl3) δ7.98 (d, J = 8.0 Hz, 2H), 7.50 (d, J = 8.0 Hz, 2H), 7.40-7.32 (m, 3H), 7.28-7.20 (m, 4H), 6.97-6. 89(m,3H),6.36(dd,J=8.0,4.0Hz,1H),4.42(dd,J=10.4,8.0Hz,1H),4.27(dd,J=10.4,4.0Hz,1H),2.40(s,3H)ppm 13 C NMR (100MHz, CDCl3) δ165.8,158.5,143.8,137.3,129.8,129.5,129.1,128.6,128.5,127.3,126.7,121.2,114.8,74.4,70.5,21.6ppm.

[0034] Synthesis example 3

[0035] Synthesis of 1-phenyl-2-phenoxyethyl p-methoxybenzoate

[0036] To a reactor, add 0.200 mmol of phenyl p-methoxybenzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide solvent. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 63% yield. 1 H NMR (400MHz, CDCl3) δ8.04(d,J=8.8Hz,2H),7.49(d,J=6.8Hz,2H),7.40-7.30(m,3H),7.28-7.22(m,2H),6.95-6. 87(m,5H),6.35(dd,J=7.6,4.0Hz,1H),4.40(dd,J=10.4,7.6Hz,1H),4.26(dd,J=10.4,4.0Hz,1H),3.81(s,3H)ppm 13C NMR (100MHz, CDCl3) δ165.4,163.5,158.5,137.4,131.8,129.4,128.6,128.4,126.7,122.4,121.1,114.8,113.6,74.2,70.5,55.3ppm.

[0037] Synthesis example 4

[0038] Synthesis of 1-phenyl-2-(2-methyl)phenoxyethyl benzoate

[0039] To a reactor, add 0.200 mmol of o-methylphenyl benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 73% yield. 1 H NMR (400MHz, CDCl3) δ8.10 (d, J = 6.8Hz, 2H), 7.57-7.49 (m, 3H), 7.45-7.32 (m, 5H), 7.14-7.07 (m, 2H), 6.87-6.78 (m,2H),6.44(dd,J=7.2,4.0Hz,1H),4.38(dd,J=10.4,7.2Hz,1H),4.29(dd,J=10.4,4.0Hz,1H),2.13(s,3H)ppm 13 C NMR (100MHz, CDCl3) δ165.7,159.1,137.2,133.1,130.7,130.1,129.7,128 .6,128.5,128.4,127.1,126.8,126.7,120.8,110.5,74.5,70.5,13.4ppm.

[0040] Synthesis example 5

[0041] Synthesis of 1-phenyl-2-phenoxyethyl p-chlorobenzoate

[0042] To a reactor, add 0.200 mmol of phenyl p-chlorobenzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide solvent. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 66% yield. 1H NMR (400MHz, CDCl3) δ8.00(d,J=8.8Hz,2H),7.49(d,J=6.8Hz,2H),7.42-7.33(m,5H),7.29-7.21(m,2H),6. 99-6.86(m,3H),6.36(dd,J=8.0,4.0Hz,1H),4.41(dd,J=10.4,8.0Hz,1H),4.27(dd,J=10.4,4.0Hz,1H)ppm 13 C NMR (100MHz, CDCl3) δ164.9,158.4,139.5,136.9,131.1,129.5,128.7,128.7,128.5,126.7,121.3,114.8,74.9,70.4ppm.

[0043] Synthesis example 6

[0044] Synthesis of 1-phenyl-2-(3-fluoro)phenoxyethyl benzoate

[0045] To a reactor, add 0.200 mmol of m-fluorophenyl benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 69% yield. 1 H NMR (400MHz, CDCl3) δ8.09 (d, J = 6.8Hz, 2H), 7.58-7.53 (m, 1H), 7.52-7.48 (m, 2H), 7.46-7.31 (m, 5H), 7.24-7.15 (m ,1H),6.71-6.60(m,3H),6.37(dd,J=7.6,4.0Hz,1H),4.40(dd,J=10.4,7.6Hz,1H),4.26(dd,J=10.4,4.0Hz,1H)ppm 13 C NMR (100MHz, CDCl3) δ165.64, 163.5 (d, J = 244.0Hz), 159.8 (d, J = 11.0Hz), 136.9, 133.6, 130.2 (d, J = 10.0Hz) ,129.9,129.8,128.7,128.4,110.4(d,J=3.0Hz),108.0(d,J=21.0Hz),102.6(d,J=25.0Hz),74.3,71.1ppm. 19F NMR (376MHz, CDCl3) δ-111.2ppm.

[0046] Synthesis Example 7

[0047] Synthesis of Methyl 2-(2-(Benzoyloxy)-2-phenylethoxy)benzoate

[0048] To a reactor, add 0.200 mmol of methyl 2-(benzoyloxy)benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide solvent. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 49% yield. 1 H NMR (400MHz, CDCl3) δ8.08(d,J=7.2Hz,2H),7.75(dd,J=8.0,2.0Hz,1H),7.53(d,J=7.2Hz,3H),7.45-7.32(m,6H),7.0 1-6.92(m,2H),6.46(dd,J=7.6,4.0Hz,1H),4.45(dd,J=10.4,7.6Hz,1H),4.37(dd,J=10.4,4.0Hz,1H),3.70(s,3H)ppm 13 C NMR (100MHz, CDCl3) δ167.0,165.5,157.6,136.9,133.2,133.1,131.7,130.0, 129.7,128.6,128.5,128.3,126.8,121.2,120.5,113.8,74.2,71.6,51.8ppm.

[0049] Synthesis example 8

[0050] Synthesis of 1-phenyl-2-(p-trifluoromethyl)phenoxyethyl benzoate

[0051] To a reactor, add 0.200 mmol of p-trifluoromethylphenyl benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 59% yield. 1H NMR(400MHz, CDCl3)δ8.1(d,J=6.8Hz,2H),7.60-7.49(m,3H),7.46-7.33(m,6H),7.22-7.04(m, 3H), 6.40 (dd, J=8.0, 4.0Hz, 1H), 4.46 (dd, J=10.4, 8.0Hz, 1H), 4.32 (dd, J=10.4, 4.0Hz, 1H) ppm 13 C NMR (100MHz, CDCl3) δ165.6,158.6,136.8,133.2,130.0,129.9,129.8,128.8,128.7,128.4,1 27.9, 126.7, 123.9 (q, J = 271Hz), 118.4, 117.9 (q, J = 4.0Hz), 111.5 (q, J = 4Hz), 74.4, 70.8ppm. 19 F NMR (376MHz, CDCl3) δ-62.8ppm.

[0052] Synthesis example 9

[0053] Synthesis of 1-phenyl-2-(1-naphthyl)oxyethyl benzoate

[0054] To a reactor, add 0.200 mmol of 1-naphthalene benzoate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide solvent. Stir and react at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 65% yield. 1 H NMR (400MHz, CDCl3) δ8.08(d,J=8.0Hz,1H),8.01(d,J=7.2Hz,2H),7.62(d,J=8.0Hz,1H),7.45(d,J=7.2Hz,2H),7.40-7.36(m,1H),7.32-7.2 5(m,7H),7.24-7.17(m,2H),6.66(d,J=7.6Hz,1H),6.48(dd,J=7.6,4.0Hz,1H),4.43(dd,J=10.4,7.6Hz,1H),4.32(dd,J=10.4,4.0Hz,1H)ppm 13C NMR (100MHz, CDCl3) δ164.5,154.9,137.1,134.4,133.1,130.6,130.0,129.7,128.7,128 .6,128.3,127.3,126.8,126.4,125.6,125.6,124.7,121.6,120.8,104.9,74.4,70.0ppm.

[0055] Synthesis example 10

[0056] Synthesis of 1-phenyl-2-phenoxyethyl acetate

[0057] To a reactor, add 0.200 mmol of phenyl acetate, 0.240 mmol of styrene oxide, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir the reaction at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 60% yield. 1 HNMR (400MHz, CDCl3) δ7.43-7.33(m,5H),7.30-7.23(m,2H),6.99-6.86(m,3H),6.15(dd,J= 8.0,4.0Hz,1H),4.27(dd,J=10.4,8.0Hz,1H),4.14(dd,J=10.4,4.0Hz,1H),2.11(s,3H)ppm 13 C NMR (100MHz, CDCl3) δ170.1,158.4,137.1,129.5,128.6,128.5,126.8,121.2,114.7,74.0,70.4,21.1ppm.

[0058] Synthesis example 11

[0059] Synthesis of 1-methyl-2-phenoxyethyl benzoate

[0060] To a reactor, add 0.200 mmol of phenyl benzoate, 0.240 mmol of 2-methyloxirane, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir the reaction at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 64% yield. 1H NMR (400MHz, CDCl3) δ8.07(dd,J=8.8,1.6Hz,2H),7.57(t,J=7.6Hz,1H),7.45(t,J=7.6Hz,2H),7.35-7.28(m,2H),7.0 2-6.93(m,3H),5.58-5.49(m,1H),4.21(dd,J=10.0,5.6Hz,1H),4.12(dd,J=10.0,4.4Hz,1H),1.52(d,J=6.4Hz,3H)ppm 13 C NMR (100MHz, CDCl3) δ166.0,158.6,132.9,130.3,129.6,129.4,128.3,121.0,114.7,70.0,69.5,16.8ppm.

[0061] Synthesis example 12

[0062] Synthesis of 1,1-dimethyl-2-phenoxyethyl benzoate

[0063] To a reactor, add 0.200 mmol of phenyl benzoate, 0.240 mmol of 2,2-dimethyloxirane, 0.016 mmol of KI, 0.120 mmol of Cs2CO3, and 0.5 mL of N,N-dimethylacetamide. Stir the reaction at 70°C under a nitrogen atmosphere for 20 hours. After completion of the reaction, the organic solvent was removed by vacuum distillation and the crude product was separated by column chromatography to obtain the desired product in a 62% yield. 1 HNMR (400MHz, CDCl3) δ7.99 (dd, J=8.4, 1.6Hz, 2H), 7.45 (t, J=7.6Hz, 1H), 7.33 (t ,J=7.6Hz,2H),7.24-7.18(m,2H),6.91-6.84(m,3H),4.16(s,2H),1.65(s,6H)ppm 13 CNMR (100MHz, CDCl3) δ165.7,158.9,132.6,131.4,129.5,129.4,128.2,121.0,114.8,81.3,73.2,23.6ppm.

[0064] It should be noted that the above embodiments do not constitute a limitation on the scope of protection claimed by the present invention. For ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for synthesizing β-phenoxycarboxylic acid ethyl ester compounds, comprising the following steps: The raw materials oxirane compound represented by Formula II, carboxylic acid aryl ester, potassium iodide, cesium carbonate, and N,N-dimethylacetamide solvent are placed in a reaction vessel, mixed, and stirred at 70°C under a nitrogen atmosphere for 20 hours. The N,N-dimethylacetamide solvent is removed by vacuum distillation and the crude product is separated by column chromatography to obtain the β-phenoxycarboxylic acid ethyl ester compound represented by Formula I. In Formula I, R1 includes, but is not limited to, one of methyl, phenyl, 4-methylphenyl, 4-methoxyphenyl, and 4-chlorophenyl. R2 includes, but is not limited to, one of phenyl, 2-methylphenyl, 3-fluorophenyl, 2-acetoxyphenyl, 4-trifluoromethylphenyl, 1-naphthyl, and 4-biphenyl. In formula II, R3 includes but is not limited to one of methyl, 1,1-dimethyl, ethyl, n-butyl, n-butyl, tert-butoxymethyl, allyloxymethyl, (2-methylphenoxy)methyl, (benzyloxy)methyl, and [(furan-2-yl)methoxy]methyl.

2. The synthesis method according to claim 1, wherein the molar ratio of the carboxylic acid aryl ester compound, the ethylene oxide compound, potassium iodide, and cesium carbonate is 1:[1.2-1.5]:[0.06-0.1]:[0.5-0.8].

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