Preparation method of (R)-2-(4-chloro-2-methylphenoxy) propionate compound

Abstract

The invention discloses a preparation method of (R)-2-(4-chloro-2-methylphenoxy) propionate compounds, which comprises the following steps: providing compounds with structures shown in formulas I and II: R-OH formula I, in the formula I, R is selected from C1-C18 alkyl substituted or unsubstituted by hydroxyl,-(R1-O) m-R1-OH,-(R4-O-CO-O) n-R4-OH,-(R4-O-CO-R10) w-OH,-R7-O (-CO-O-(R6-O-) p) q-R7-OH, R1 is alkylene of C2-C4, m is an integer of 4-28, and R2 is an integer of 4-28; r4 is a C3-C15 alkylene group or # imgabs0 # n is an integer from 1 to 20; r10 is # imgabs1 # w which is an integer from 1 to 15; r < 6 > is isopropylidene, R < 7 > is C2-C5 alkylene, p is an integer of 1-5, and q is an integer of 5-30; in the formula II, R2 and R3 are independently selected from H, C1, Br and I, and at least one of R2 and R3 is C1 or Br or I; compounds shown in the formula I and the formula II react under the catalytic condition to generate a compound shown in the formula III, wherein R, R2 and R3 are defined as above; the compound shown in the formula III and 4-chloro-o-cresol are catalyzed by an etherification catalyst to generate a compound shown in a formula IV, and in the formula IV, R is defined as above; # imgabs2 #

Description

Technical Field

[0001] The present application belongs to the technical field of root inhibitor synthesis, and in particular to a method for preparing a (R)-2-(4-chloro-2-methylphenoxy) propionate compound. Background Art

[0002] In recent years, as the country attaches great importance to building energy conservation, the green roof system has been widely promoted and applied. The effective life of the green roof system depends to a certain extent on the root penetration resistance of the root penetration resistant waterproof material. There are two root blocking principles of puncture resistant waterproof membranes: one is to use the material properties of the waterproof membrane itself and the firmness of the joints to achieve the purpose of root blocking, and the other is to add root blocking agents to the waterproof membranes to use the root blocking effect of the root blocking agent to inhibit plant roots from penetrating the waterproof layer.

[0003] However, the existing root inhibitor synthesis steps are more and take a long time, often requiring three to five days. The raw materials used in the method with fewer synthesis steps are generally more expensive and even cannot be purchased from the market. On the other hand, the residual metal catalyst in the prior art may affect the use of the root inhibitor, such as causing the coil to decompose when applied to the coil, reducing the product life. Summary of the invention

[0004] The preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionic acid ester compound provided in the embodiment of the present application can prepare a monomeric or polymeric root inhibitor in two simple steps through esterification and etherification reactions.

[0005] In a first aspect, the present application provides a method for preparing a (R)-2-(4-chloro-2-methylphenoxy) propionate compound, comprising:

[0006] Provide compounds with structures shown in Formula I and II:

[0007] R-OH Formula I,

[0008]

[0009] In formula I, R is selected from C1-C18 alkyl substituted or unsubstituted by hydroxyl, -(R1-O) m -R1-OH, -(R4-O-CO-O) n -R4-OH、-(R4-O-CO-OR 10 ) w -OH, -R7-O(-CO-O-(R6-O-) p ) q -R7-OH, wherein R1 is a C2-C4 alkylene group, m is an integer of 4 to 28; R4 is a C3-C15 alkylene group or n is an integer of 1 to 20; R4 is a C3-C15 alkylene group, R 10 for w is an integer of 1 to 15; R6 is an isopropylidene group, R7 is a C2 to C5 alkylene group, p is an integer of 1 to 5, and q is an integer of 5 to 30;

[0010] In formula II, R2 is independently selected from H, Cl, Br, I, R3 is independently selected from H, Cl, Br, I, and at least one of R2 and R3 is Cl or Br or I;

[0011] The compounds represented by formula I and formula II are reacted under esterification catalyst conditions to generate the compound represented by formula III:

[0012]

[0013] In formula III, R, R2, and R3 are as defined above;

[0014] The compound represented by formula III is reacted with 4-chloro-o-cresol under catalytic conditions of an etherification catalyst to produce a compound represented by formula IV:

[0015]

[0016] In formula IV, R is as defined above.

[0017] According to an embodiment of one aspect of the present application, R is selected from a C4-C18 alkyl group which is substituted or unsubstituted by a hydroxyl group.

[0018] According to an embodiment of one aspect of the present application, R is -(R1-O) m -R1-OH, R1 is a C2-C3 alkyl group, and m is an integer from 5 to 11.

[0019] According to an embodiment of one aspect of the present application, R is -(R4-O-CO-O) n -R4-OH, R4 is a C5-C6 alkyl group or n is an integer from 1 to 10.

[0020] According to an embodiment of one aspect of the present application, R is selected from -(R4-O-CO-OR 10 ) w -OH, R4 is a C3-C15 alkylene group, R 10 for w is an integer from 4 to 10.

[0021] According to an embodiment of one aspect of the present application, R is -R7-O(-CO-O-(R6-O-) p ) q-R7-OH, R6 is isopropylidene, R7 is -CH2-CH(R8)-, R8 is H or methyl, p is an integer of 1 to 2, and q is an integer of 5 to 25.

[0022] According to an embodiment of one aspect of the present application, the boiling point of the compound represented by formula I is <200° C., and the compound represented by formula I reacts with the compound represented by formula II at a molar ratio of carboxyl group:hydroxyl group=1:(1.1-5).

[0023] According to an embodiment of one aspect of the present application, the compound represented by formula I with a boiling point of <200°C is selected from methanol, ethanol, propanol, 1,3-propylene glycol, isopropanol, n-butanol, isobutanol, 1,4-butanediol, 2-methyl-1,3-propanediol, n-pentanol, isopentanol, 1,5-pentanediol, isopentanol, neopentyl glycol, n-hexanol, 1,6-hexanediol, n-heptanol, 1,7-heptanediol, octanol, isooctanol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,4-cyclohexanediol or a combination thereof.

[0024] According to an embodiment of one aspect of the present application, the compound represented by formula I is a compound having a boiling point ≥200°C, and the compound represented by formula I reacts with the compound represented by formula II at a molar ratio of carboxyl:hydroxyl = (0.9-1):1.

[0025] According to an embodiment of one aspect of the present application, the compound represented by formula I with a boiling point ≥200°C is selected from 2,2-dimethyl-1,3-propanediol, 2-ethyl-1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, n-nonanol, 2-butyl-2-ethyl-1,3-propanediol, n-decanol, 1,10-decanediol, undecyl alcohol, 1,11-undecanediol, dodecanol, 1,12-dodecanediol. , tridecanol, 1,13-tridecyl glycol, tetradecanol, 1,14-tetradecanol, pentadecanol, 1,15-pentadecanediol, 1-hexadecanol, heptadecanol, 1-octadecyl alcohol, polyethylene glycol having a molecular weight of 200 to 600, polypropylene glycol having a molecular weight of 400 to 600, polybutylene glycol having a molecular weight of 200 to 2000, polypropylene carbonate diol having a molecular weight of 500 to 3000, polycarbonate diol having a molecular weight of 500 to 3000, or a combination thereof.

[0026] According to an embodiment of one aspect of the present application, the compound represented by Formula I is selected from polyethylene glycol 200, polyethylene glycol 300, polyethylene glycol 500, polypropylene glycol 400, polypropylene glycol 600, polybutylene glycol 250, and polybutylene glycol 650.

[0027] According to an embodiment of one aspect of the present application, the compound represented by Formula I is selected from polypropylene carbonate diol having a number average molecular weight of 500 to 2000, polycarbonate-1,5-pentanediol-1,6-hexanediol ester diol having a number average molecular weight of 1900 to 2000, and polycarbonate-1,6-hexanediol ester diol having a number average molecular weight of 1800 to 2200.

[0028] According to an embodiment of one aspect of the present application, the esterification catalyst is selected from p-toluenesulfonic acid, methanesulfonic acid, concentrated sulfuric acid or a combination thereof.

[0029] According to an embodiment of one aspect of the present application, the compound represented by formula II is selected from 2-chloropropionic acid, 2,2-dichloropropionic acid, 2-bromopropionic acid, 2,2-bromopropionic acid, and 2-iodopropionic acid.

[0030] According to an embodiment of one aspect of the present application, the compound represented by formula III is reacted with 4-chloro-o-cresol at a molar ratio of (1.1-1.3):1 under etherification catalyst conditions.

[0031] According to an embodiment of one aspect of the present application, the etherification catalyst is selected from cesium carbonate, potassium carbonate, sodium carbonate, sodium bicarbonate or a combination thereof.

[0032] The preparation method of the (R)-2-(4-chloro-2-methylphenoxy)propionate compound of the embodiment of the present application is to firstly prepare the halogenated propionate by an esterification reaction between the alcohol compound shown in formula I and a halogenated propionic acid containing a halogen C1, Br or I on the β carbon, and then prepare the (R)-2-(4-chloro-2-methylphenoxy)propionate compound by an etherification reaction between the halogenated propionate and 4-chloro-o-cresol. The preparation method is simple and quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0034] Figure 1 This is the infrared absorption spectrum of (R)-2-(4-chloro-2-methylphenoxy)propionic acid n-octyl ester prepared in Example 1 of the present application.

[0035] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of (R)-2-(4-chloro-2-methylphenoxy)propionic acid n-octyl ester prepared in Example 1 of the present application.

[0036] Figure 3 This is the infrared absorption spectrum of (R)-2-(4-chloro-2-methylphenoxy)propanoic acid isooctyl ester prepared in Example 7.

[0037] Figure 4 This is the infrared absorption spectrum of (R)-2-(4-chloro-2-methylphenoxy)propionic acid polyethylene glycol ester prepared in Example 21.

[0038] Figure 5 This is the mass spectrum of (R)-2-(4-chloro-2-methylphenoxy)propionic acid polyethylene glycol ester prepared in Example 21.

[0039] Figure 6 This is a schematic diagram of the structure of the test box used for testing the root barrier effect of the (R)-2-(4-chloro-2-methylphenoxy) propionate compound prepared in Example 1-26.

[0040] Figure numerals: 1. Plant cover layer; 2. Planting soil layer; 3. Filtration layer; 4. Drainage layer; 5. Moisture retaining layer; 6. Root barrier layer, i.e., soil layer containing root inhibitor solution with root blocking effect; 7. Anti-leakage layer; 8. Site surface / top floor of original building. DETAILED DESCRIPTION

[0041] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0043] As mentioned in the background technology section, the principle of chemical root inhibition is: in the asphalt mixing process, an environmentally friendly chemical root inhibitor that is harmless to the environment and plant roots is directly added, so that it is evenly distributed in the modified asphalt layer of the waterproof membrane. By utilizing the biochemical reaction between the additive and the plant roots, when the plant roots grow into the asphalt layer, they are keratinized under the action of the added root inhibitor and grow in parallel, thereby achieving the purpose of inhibiting the plant roots from penetrating the waterproof layer.

[0044] In the process of studying and improving the existing technology, the applicant found that the root inhibitor in the existing technology is generally prepared by direct esterification, which is a relatively mature preparation method. However, metal ions are introduced during the preparation process. When the root inhibitor is subsequently applied to the coil product, the metal ions will cause the coil to decompose, reducing the service life of the coil product. In addition, the existing preparation method has many synthesis steps and takes a long time.

[0045] In order to solve the problems of the prior art, the present invention provides a novel method for preparing a root inhibitor (R)-2-(4-chloro-2-methylphenoxy) propionate compound. That is, through the method for preparing a (R)-2-(4-chloro-2-methylphenoxy) propionate compound of the present invention, a (R)-2-(4-chloro-2-methylphenoxy) propionate monomer can be prepared, and a (R)-2-(4-chloro-2-methylphenoxy) propionate polymer can also be prepared as a root inhibitor.

[0046] The following is an introduction to the preparation method of the (R)-2-(4-chloro-2-methylphenoxy)propionic acid ester compound provided in the examples of the present application.

[0047] In an embodiment of the present application, the preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionate compound comprises: providing compounds of structures shown in Formula I and II respectively:

[0048] R-OH Formula I,

[0049]

[0050] In formula I, R is selected from C1-C18 alkyl substituted or unsubstituted by hydroxyl, -(R1-O) m -R1-OH, -(R4-O-CO-O) n -R4-OH、-(R4-O-CO-OR 10 ) w -OH, -R7-O(-CO-O-(R6-O-) p ) q -R7-OH; wherein R1 is a C2-C4 alkylene group, m is an integer of 4 to 28; R4 is a C3-C15 alkylene group or n is an integer of 1 to 20; R4 is a C3-C15 alkylene group, R 10 for w is an integer of 1 to 15; R6 is an isopropylidene group, R7 is a C2 to C5 alkylene group, p is an integer of 1 to 5, and q is an integer of 5 to 30;

[0051] In formula II, R2 is independently selected from H, Cl, Br, I, R3 is independently selected from H, Cl, Br, I, and at least one of R2 and R3 is Cl or Br or I;

[0052] The compounds represented by formula I and formula II are reacted under esterification catalyst conditions to generate the compound represented by formula III:

[0053]

[0054] In formula III, R, R2, and R3 are as defined above;

[0055] The compound represented by formula III is reacted with 4-chloro-o-cresol under catalytic conditions of an etherification catalyst to produce a compound represented by formula IV:

[0056]

[0057] In formula IV, R is as defined above.

[0058] It should be noted that the structural formula of the isopropylidene group represented by R6 is -CH2CH(CH3)-.

[0059] The preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionate compound of the embodiment of the present application provides a new preparation method of the root inhibitor compound, firstly, an alcohol compound of formula I is subjected to an esterification reaction with a 2-halopropionic acid containing a halogen C1, Br or I on the β carbon to prepare a 2-halopropionate, and then the 2-halopropionate is subjected to an etherification reaction with 4-chloro-o-cresol to prepare a (R)-2-(4-chloro-2-methylphenoxy) propionate compound. The preparation method is simple and quick.

[0060] The preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionic acid ester compound of the embodiment of the present application is a compound prepared by a two-step reaction of esterification and etherification. The compound can be either a monomer compound with a root inhibition effect or a polymer compound with a root inhibition effect, so that the prepared root inhibitor is suitable for the root inhibition needs in different situations and obtains different root inhibition effects.

[0061] In some embodiments of the present application, R is selected from C1-C18 alkyl groups substituted or unsubstituted by hydroxyl groups. Among them, the C1-C18 alkyl group not substituted by hydroxyl groups, that is, the compound represented by Formula I, is an alcohol compound containing a monohydroxyl group, which is reacted with 2-halopropionic acid and 4-chloro-o-cresol in sequence to obtain a (R)-2-(4-chloro-2-methylphenoxy) propionate monomer compound with a root-blocking effect. The C1-C18 alkyl group substituted by hydroxyl groups, that is, the compound represented by Formula I, is an alcohol compound containing at least two hydroxyl groups, so that it can react with 2-halopropionic acid to obtain an ester compound containing two 2-halopropionic acid groups, and then react with 4-chloro-o-cresol to prepare a compound containing two 2-(4-chloro-2-methylphenoxy) propionate groups.

[0062] Optionally, R is selected from a C4-C18 alkyl group which is substituted or unsubstituted with a hydroxyl group, so that the compound represented by Formula I reacts with the compound represented by Formula II to form a suitable (R)-2-(4-chloro-2-methylphenoxy)propionic acid ester compound.

[0063] In some embodiments of the present application, the compound of formula I with a boiling point of <200°C is selected from methanol, ethanol, propanol, 1,3-propylene glycol, isopropanol, n-butanol, isobutanol, 1,4-butanediol, 2-methyl-1,3-propylene glycol, n-pentanol, isopentanol, 1,5-pentanediol, isopentanol, neopentyl glycol, n-hexanol, 1,6-hexanediol, n-heptanol, 1,7-heptanediol, n-octanol, isooctyl alcohol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,4-cyclohexanediol or a combination thereof.

[0064] In some embodiments of the present application, the boiling point of the compound shown in Formula I is <200°C. The compound shown in Formula I with a boiling point <200°C reacts with the compound shown in Formula II at a molar ratio of carboxyl group:hydroxyl group=1:(1.1-5). Exemplarily, the compound shown in Formula I reacts with the compound shown in Formula II at a molar ratio of carboxyl group:hydroxyl group of 1:1.2, 1:1.5, 1:1.8, 1:2.0, 1:2.5, 1:3.0, 1:3.2, 1:3.6, 1:4.5, 1:4.8, 1:5. By selecting the molar ratio of carboxyl group and hydroxyl group in this limited range, the 2-halopropionic acid containing carboxyl group can be fully reacted to obtain 2-halopropionic acid ester compounds.

[0065] In some optional embodiments of the present application, the preparation method includes mixing the compound of formula I with a boiling point of <200°C with the compound of formula II in a molar ratio of carboxyl:hydroxyl = 1:(1.1~5), adding an esterification catalyst and heating to 120°C~180°C, stirring at normal pressure for 0.2 hour~0.5 hour to react, then evacuating to -0.02MPa~0.06MPa to remove moisture, continuing the reaction for 2 hours~4 hours until the compound of formula II is completely reacted; then increasing the vacuum degree to -0.09MPa~0.1MPa to completely remove the excess compound of formula I, wherein the extracted condensed liquid can recover part of the excess compound of formula I; to obtain the compound of formula III.

[0066] In some embodiments of the present application, the boiling point of the compound represented by formula I is ≥200°C, and the compound represented by formula I with a boiling point ≥200°C reacts with the compound represented by formula II at a molar ratio of carboxyl group:hydroxyl group = (0.9-1): 1. By selecting the molar ratio of carboxyl group to hydroxyl group in this limited range, the 2-halogenated propionic acid compound represented by formula II containing a carboxyl group can be fully reacted with the polymeric alcohol compound represented by formula I to obtain a 2-halogenated propionic acid ester compound.

[0067] In some embodiments of the present application, the compound of formula I with a boiling point ≥ 200°C is selected from 2,2-dimethyl-1,3-propanediol, 2-ethyl-1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, n-nonanol, 2-butyl-2-ethyl-1,3-propanediol, n-decanol, 1,10-decanediol, undecanol, 1,11-undecanediol, dodecanol, 1,12-dodecanediol. , tridecanol, 1,13-tridecyl glycol, tetradecanol, 1,14-tetradecanol, pentadecanol, 1,15-pentadecanediol, hexadecanol, heptadecanol, 1-octadecyl alcohol, polyethylene glycol having a molecular weight of 200 to 600, polypropylene glycol having a molecular weight of 400 to 600, polybutylene glycol having a molecular weight of 200 to 2000, polypropylene carbonate diol having a molecular weight of 500 to 3000, polycarbonate diol having a molecular weight of 500 to 3000, or a combination thereof.

[0068] In some embodiments of the present application, R is selected from -(R1-O)m-R1-OH, R1 is a C2-C4 alkylene group, and m is an integer of 5 to 11. For example, the compound of the structure shown in Formula I is polyethylene glycol 200-600, and polyethylene glycol 200 (ie, PEG200), polyethylene glycol 300 (ie, PEG300), and polyethylene glycol 500 (ie, PEG500) can be selected. Polypropylene glycol 400-600 can be selected from polypropylene glycol 400 (ie, PPG400) and polypropylene glycol 600 (ie, PPG600). Polybutylene glycol 200-2000 can be selected from polybutylene glycol 250 (i.e. PTMG250, with a molecular weight of 250±25), polybutylene glycol 650 (i.e. PTMG650, with a molecular weight of 650±25), polybutylene glycol 1000 (i.e. PTMG1000, with a molecular weight of 1000±50), polybutylene glycol 1400 (i.e. PTMG1400, with a molecular weight of 1400±50), and polybutylene glycol 1800 (i.e. PTMG1800, with a molecular weight of 1800±50).

[0069] In some embodiments of the present application, R is selected from -(R4-O-CO-O) n -R4-OH, R4 is C5-C6 alkylene or n is an integer from 1 to 10. R is selected from -(R4-O-CO-O) n -R4-OH means that the compound shown in formula I is a polycarbonate diol, and its corresponding R4 can be optionally -(CH2)5-, -(CH2)6-, or R4 is 1,4-cyclohexane dimethylene, that is, -CH2(C6H 10 )CH2-; or R4 is

[0070] For example, the polycarbonate diol can be selected from polycarbonate-1,5-pentanediol-1,6-hexanediol ester diol with a number average molecular weight of 1900 to 2000, and polycarbonate-1,6-hexanediol ester diol with a number average molecular weight of 1800 to 2200. Or the polycarbonate diol can be selected from polycarbonate diphenyl diol with a number average molecular weight of 500 to 3000. For example, the compound shown in Formula I can be selected from polycarbonate diphenyl diol with a molecular weight of 500 to 2000, such as polycarbonate diphenyl diols of UH series of Japan Ube UH-50, UH-100, and UH-200, or polycarbonate diphenyl diols of PH series of Japan Ube PH-50, PH-100, and PH-200, or polycarbonate diphenyl diols of Japan Ube brand BH-100.

[0071] It should be noted that the polycarbonate diol used in the present application is a polycarbonate diol in liquid state obtained by copolymerization. For example, the polycarbonate diol can be selected from the polycarbonate diol of McLean P997425, which has an average molecular weight of 500 and is a colorless viscous liquid. The polycarbonate diol of McLean P997426 can also be selected, which has an average molecular weight of 1000 and is a colorless viscous liquid. The polycarbonate diol can also be selected from the polycarbonate diol of McLean P99427, which has an average molecular weight of 2000 and is a colorless viscous liquid. Alternatively, the polycarbonate diol of McLean P99428 can also be selected, which has an average molecular weight of 3000 and is a colorless viscous liquid.

[0072] In some embodiments of the present application, R is selected from -(R4-O-CO-OR 10 ) w -OH, R4 is a C3-C15 alkylene group, R 10 for w is an integer from 1 to 15. R is selected from -(R4-O-CO-OR 10 ) w -OH, that is, the compound represented by formula I is a polycarbonate diol, but its repeating structural unit is a carbonate structural group with an alkylene group R4 and a structural group R containing a benzene ring connected to both sides. 10 For example, the structural formula of the polycarbonate diol referred to herein may be That is, R 10 can be Replace with the corresponding structure Optionally, W is an integer from 4 to 10.

[0073] In some embodiments of the present application, R is selected from -R7-O(-CO-O-(R6-O-) p ) q-R7-OH, R6 is isopropylene, R7 is -CH2-CH(R8)-, R8 is H or methyl, that is, R7 is a C2-C3 straight chain alkylene or isopropylene, p is an integer of 1 to 2, and q is an integer of 5 to 25. Optionally, R7 is -CH2CH2-, or isopropylene, that is, -CH2CHCH3-. That is, the compound shown in formula I is a polypropylene carbonate diol with a molecular weight of 500 to 3000. Optionally, the compound shown in formula I is polypropylene carbonate ethylene glycol, or polypropylene carbonate diol. For example, the polypropylene carbonate diol can be at least PPCD221 (molecular weight 2000), PPCD222 (molecular weight 2000), PPCD231 (molecular weight 3000), PPCD236 (molecular weight 3000), and PPCD237 (molecular weight 3000) of Dazhi Technology. Taking the polypropylene carbonate diol with the brand PPCD231 as an example, it includes the following structure:

[0074]

[0075] Among them, R6 is -CH2CHCH3-, R7 is also -CH2CHCH3-, p=2; n=18, that is, q.

[0076] In some optional embodiments of the present application, the preparation method includes mixing the compound represented by formula I having a boiling point ≥200°C with the compound represented by formula II in a molar ratio of carboxyl:hydroxyl = (0.9~1):1, adding an esterification catalyst and heating to 90°C~150°C, stirring at normal pressure for 0.2 hour~0.5 hour to react, then evacuating to -0.09MPa~0.1MPa to remove moisture, and continuing the reaction for 2 hours~4 hours, until the compound represented by formula II reacts completely to obtain the compound represented by formula III.

[0077] In some embodiments of the present application, the esterification catalyst is selected from p-toluenesulfonic acid, methanesulfonic acid, concentrated sulfuric acid or a combination thereof.

[0078] In some embodiments of the present application, the compound represented by formula II is selected from 2-chloropropionic acid, 2,2-dichloropropionic acid, 2-bromopropionic acid, 2,2-bromopropionic acid, and 2-iodopropionic acid.

[0079] For example, the compound represented by Formula I is R-OH, and the compound represented by Formula II is 2-bromopropionic acid, then the corresponding reaction formula of the compound represented by Formula I and the compound represented by Formula II is:

[0080]

[0081] The reaction obtains a compound represented by formula III having a corresponding R group, namely a 2-bromopropionic acid ester compound.

[0082] In an embodiment of the present application, the preparation method firstly carries out an esterification reaction of a halopropionic acid whose β-carbon is substituted by at least one halogen selected from Cl, Br, and I with an alcohol compound that is at least a monohydric alcohol to obtain an esterification product, i.e., 2-halopropionic acid ester, and then carries out an etherification reaction of the 2-halopropionic acid ester with 4-chloro-o-cresol to prepare a monomeric compound or a polymeric compound containing a root inhibitor group.

[0083] In some embodiments of the present application, the compound shown in formula III is reacted with 4-chloro-o-cresol at a molar ratio of (1.1-1.3):1 under the condition of an etherification catalyst for etherification reaction. The compound shown in formula III reacts with 4-chloro-o-cresol at a limited molar ratio, so that the 2-halogenated propionate compound can react as much as possible to generate a root inhibitor containing a single 4-chloro-2-methylphenoxy group, so as to better achieve the root inhibitor effect. Exemplarily, the compound shown in formula III reacts with 4-chloro-o-cresol at a molar ratio of 1.15:1, 1.2:1, and 1.25:1.

[0084] In some embodiments of the present application, the etherification catalyst is selected from cesium carbonate, potassium carbonate, sodium carbonate, sodium bicarbonate or a combination thereof.

[0085] In some embodiments of the present application, the compound shown in formula III and 4-chloro-o-cresol are subjected to an etherification reaction at a molar ratio of (1.1 to 1.3):1 under the catalytic conditions of an etherification catalyst to prepare a (R)-2-(4-chloro-2-methylphenoxy) propionate compound. The compound shown in formula III is an esterification reaction product, wherein the compound shown in formula III and the etherification catalyst are soluble in good solvents such as acetonitrile, DMF, and ethanol, and 4-chloro-o-cresol can also be dissolved in a good solvent, and then the solution containing 4-chloro-o-cresol is slowly added dropwise to the solution containing the compound shown in formula III and the etherification catalyst, and the addition time is controlled to be 3 to 5 hours. After the addition is completed, stirring is continued for 6 to 10 hours until the 4-chloro-o-cresol reacts completely.

[0086] For example, the compound shown in formula III is 2-bromopropionate, and its reaction formula with 4-chloro-o-cresol is:

[0087]

[0088] The reaction yields a (R)-2-(4-chloro-2-methylphenoxy)propionic acid ester compound having a corresponding R group.

[0089] In the embodiments of the present application, the halogen atom on the β-carbon of the 2-halopropionic acid ester can undergo an etherification reaction with the hydrogen atom of the phenolic hydroxyl group on 4-chloro-o-cresol to obtain a monomer compound containing a root inhibitor group, such as (R)-2-(4-chloro-2-methylphenoxy) propionate methyl ester, (R)-2-(4-chloro-2-methylphenoxy) propionate ethyl ester, (R)-2-(4-chloro-2-methylphenoxy) propionate butyl ester, (R)-2-(4-chloro-2-methylphenoxy) propionate octyl ester, and (R)-2-(4-chloro-2-methylphenoxy) propionate octanediol ester. (R)-2-(4-chloro-2-methylphenoxy) propionate compounds containing polymer groups can also be prepared, such as (R)-2-(4-chloro-2-methylphenoxy) propionate polyethylene glycol ester, (R)-2-(4-chloro-2-methylphenoxy) propionate polypropylene glycol ester, (R)-2-(4-chloro-2-methylphenoxy) propionate polybutylene glycol ester, (R)-2-(4-chloro-2-methylphenoxy) propionate polycarbonate diol ester, and (R)-2-(4-chloro-2-methylphenoxy) propionate polypropylene carbonate glycol ester.

[0090] The method for preparing the (R)-2-(4-chloro-2-methylphenoxy)propionate compounds of the embodiments of the present application has fewer reaction steps, and only two steps are required to prepare the (R)-2-(4-chloro-2-methylphenoxy)propionate compounds; and the reaction time for preparing the (R)-2-(4-chloro-2-methylphenoxy)propionate compounds is shorter, and the preparation time can be shortened to one day compared to the three-day preparation time required by the existing preparation method; the catalyst is easy to remove and will not affect subsequent applications; the reaction conditions are milder, and the method for preparing the (R)-2-(4-chloro-2-methylphenoxy)propionate compounds of the embodiments of the present application has good reaction versatility and can be applied to raw materials containing different R groups.

[0091] Example

[0092] Unless otherwise specified, the raw materials used in the examples of the present application can be obtained through commercial channels. The following are the raw material models / brands used in some examples and their manufacturers: polyethylene glycol (PEG300), purchased from Merck's Sigma-Aldrich reagent; polypropylene glycol (PPG400), purchased from Merck's Sigma-Aldrich reagent; polycarbonate diol (PCDL), model: P99425, number average molecular weight of 500; model: P99426, number average molecular weight of 1000; model: P99427, number average molecular weight of 2000; all are colorless viscous liquids, and all are purchased from MacLean Company.

[0093] Example 1

[0094] The preparation method of (R)-2-(4-chloro-2-methylphenoxy) propionic acid n-octyl ester comprises:

[0095] S1, 2-bromopropionic acid and n-octanol are mixed in a molar ratio of 1:3, p-toluenesulfonic acid is added as an esterification catalyst, the temperature is raised to 150°C, and the esterification reaction is carried out by stirring at normal pressure for 0.5 hours, and the water is removed by vacuuming to -0.05MPa, and then the reaction is continued for 3 hours until the 2-bromopropionic acid reacts completely, and then the vacuum degree is increased to -0.1MPa to completely remove the excess n-octanol, and the condensed liquid extracted can recover part of the excess n-octanol to obtain 2-bromopropionic acid n-octyl ester. The reaction formula of step S1 is:

[0096]

[0097] In formula VII, R5 is -(CH2)7CH3.

[0098] S2, dissolving the 2-bromopropionic acid n-octyl ester prepared in S1 and cesium carbonate as an etherification catalyst in acetonitrile, dissolving 4-chloro-o-cresol with acetonitrile, and slowly dropping the acetonitrile solution of 4-chloro-o-cresol into the solution containing 2-bromopropionic acid n-octyl ester and cesium carbonate, the dropping time is 4 hours, wherein the molar ratio of 2-bromopropionic acid n-octyl ester to 4-chloro-o-cresol is 1.2:1; after the dropwise addition is completed, stirring is continued for 6 hours until 4-chloro-o-cresol is completely reacted to obtain (R)-2-(4-chloro-2-methylphenoxy) propionic acid n-octyl ester. The reaction formula of step S2 is:

[0099]

[0100] In formula VIII, the R5 group is as defined above and is a C8 n-octyl group.

[0101] Example 2-Example 9

[0102] The preparation methods of the (R)-2-(4-chloro-2-methylphenoxy)propionic acid ester compounds of Examples 2 to 9 are basically the same as the preparation method of the (R)-2-(4-chloro-2-methylphenoxy)propionic acid octyl ester of Example 1, except that, as shown in Table 1, the type and amount of the raw material 2 shown in Formula II in Step S1 are different, and the amount of compound 1 in Step S2 is different.

[0103] Example 10

[0104] The preparation method of (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester comprises:

[0105] S1. Mix 2-bromopropionic acid and polyethylene glycol (PEG300) in a molar ratio of 0.9:1, add methylsulfonic acid as an esterification catalyst, heat to 120°C, stir at normal pressure for 0.5 hour to carry out esterification reaction, vacuum at -0.06 MPa to remove moisture, and then continue to react for 4 hours until 2-bromopropionic acid reacts completely to obtain 2-bromopropionic acid polyethylene glycol ester.

[0106] S2. Dissolve the 2-bromopropionic acid polyethylene glycol ester prepared in S1 and cesium carbonate as an etherification catalyst in acetonitrile, dissolve 4-chloro-o-cresol with acetonitrile, and slowly drop the acetonitrile solution of 4-chloro-o-cresol into the solution containing 2-bromopropionic acid polyethylene glycol ester and cesium carbonate. The dropping time is 4 hours, wherein the molar ratio of 2-bromopropionic acid polyethylene glycol ester to 4-chloro-o-cresol is 1.2:1. After the dropwise addition is completed, continue stirring for 6 hours until 4-chloro-o-cresol is completely reacted to obtain (R)-2-(4-chloro-2-methylphenoxy)propionic acid polyethylene glycol ester.

[0107] Examples 11-18

[0108] The preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionate compounds of Examples 11-18 is basically the same as the preparation method of the (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester of Example 10, except that: as shown in Table 1, the amount of raw material 1 shown in Formula I is different from the type and amount of raw material 2 shown in Formula II. Among them, Examples 11 to 12 respectively use polyethylene glycol (PEG) with a molecular weight of 300, Examples 13 to 15 respectively use polypropylene glycol (PPG) with a molecular weight of 400, and Examples 16 to 18 respectively use polycarbonate diols (PCDL) with average molecular weights of 500, 1000, and 2000.

[0109] Embodiment 19

[0110] The preparation method of (R)-2-(4-chloro-2-methylphenoxy)octyl propionate comprises:

[0111] S1. Mix 2-chloropropionic acid and n-octanol in a molar ratio of 1:1.3, add p-toluenesulfonic acid as a catalyst, heat to 150°C, stir at normal pressure for 0.5 hour for esterification reaction, evacuate to -0.05MPa to remove moisture, and then continue to react for 3 hours until the 2-chloropropionic acid reacts completely, and then increase the vacuum degree to -0.1MPa to completely remove excess n-octanol. The extracted condensed liquid can recover part of the excess n-octanol to obtain 2-chloropropionic acid n-octyl ester.

[0112] S2. Dissolve the 2-octyl 2-chloropropionate prepared in S1 and cesium carbonate as an etherification catalyst in acetonitrile, dissolve 4-chloro-o-cresol with acetonitrile, and slowly drop the acetonitrile solution of 4-chloro-o-cresol into the solution containing 2-octyl 2-chloropropionate and cesium carbonate. The dropping time is 4 hours, wherein the molar ratio of 2-octyl 2-chloropropionate to 4-chloro-o-cresol is 1.2:1. After the dropwise addition is completed, continue stirring for 6 hours until 4-chloro-o-cresol is completely reacted to obtain (R)-2-(4-chloro-2-methylphenoxy)propionic acid octyl ester.

[0113] Embodiment 20

[0114] The preparation method of (R)-2-(4-chloro-2-methylphenoxy)propanoic acid n-octyl ester in this embodiment is basically the same as the preparation method of (R)-2-(4-chloro-2-methylphenoxy)propanoic acid n-octyl ester in Example 19, except that: as shown in Table 1, the amount of n-octanol in step S1 is 2.2 mol, and the type and amount of compound 1 in step S2 are different.

[0115] Examples 21-26

[0116] The preparation methods of (R)-2-(4-chloro-2-methylphenoxy) propionate compounds of Examples 21-26 are basically the same as the preparation method of (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester of Example 10, except that: as shown in Table 1, the amount of the raw material compound shown in Formula I in Step S1 and the type and amount of the raw material 2 shown in Formula II are different, and the type and amount of the compound 1 in Step S2 as shown in Table 2 are different. Among them, Examples 25 and 26 use polycarbonate diols (PCDL) with average molecular weights of 500 and 1000, respectively.

[0117] Comparative Example 1

[0118] A method for preparing a (R)-2-(4-chloro-2-methylphenoxy) propionate octyl root inhibitor, wherein the (R)-2-(4-chloro-2-methylphenoxy) propionate octyl root inhibitor is prepared according to Example 1 disclosed in Chinese Patent 201710675838.4, and the preparation time is more than 25 hours.

[0119] Comparing Example 1 with Comparative Example 1, both are for preparing (R)-2-(4-chloro-2-methylphenoxy) propionate octyl root inhibitor. Example 1 of the present application not only reduces the preparation steps, but also reduces the time used for preparing (R)-2-(4-chloro-2-methylphenoxy) propionate octyl root inhibitor, from a total of more than 25 hours in Comparative Example 1 to about 13.5 hours, and the preparation time is shortened by at least 46%.

[0120]

[0121]

[0122] Characterization

[0123] The molecular absorption infrared spectra of (R)-2-(4-chloro-2-methylphenoxy)propionate prepared in Example 1, the isooctyl (R)-2-(4-chloro-2-methylphenoxy)propionate prepared in Example 7, and the (R)-2-(4-chloro-2-methylphenoxy)propionate polyethylene glycol prepared in Example 21 were measured respectively, and the nuclear magnetic resonance hydrogen spectrum of the (R)-2-(4-chloro-2-methylphenoxy)propionate prepared in Example 1 was measured, and the mass spectrum of the (R)-2-(4-chloro-2-methylphenoxy)propionate polyethylene glycol prepared in Example 21 was measured.

[0124] like Figure 1 As shown, (R)-2-(4-chloro-2-methylphenoxy) propionic acid n-octyl ester is at 1000cm -1 ~1300cm -1 The position has an infrared absorption peak unique to ether bonds, namely at 1141.8 cm -1 、1244.8cm -1 (Ar-OR), and 1756.4cm -1 There is an infrared characteristic absorption peak at (-COO-); the infrared absorption peak of Ar-OR is the absorption peak at the connection between the n-octyl propionate group and the 4-chloro-2-methylphenoxy group. Figure 1 It can be concluded from the infrared absorption spectrum that the product prepared in Example 1 of the present application is (R)-2-(4-chloro-2-methylphenoxy) propionic acid n-octyl ester containing an ether group. Figure 2 As shown, the H NMR spectrum of (R)-2-(4-chloro-2-methylphenoxy) propionate is similar to the H NMR spectrum of the standard (R)-2-(4-chloro-2-methylphenoxy) propionate. Figure 1 The above results show that Example 1 prepared R)-2-(4-chloro-2-methylphenoxy) propionic acid n-octyl ester.

[0125] like Figure 3 As shown in the infrared absorption spectrum of (R)-2-(4-chloro-2-methylphenoxy) propionate, (R)-2-(4-chloro-2-methylphenoxy) propionate isooctyl at 1000 cm -1 ~1300cm -1 The position has an infrared absorption peak unique to ether bonds, namely at 1141cm -1 、1244cm -1 (Ar-OR) and 1736cm -1 There is an infrared characteristic absorption peak at (-COO-). Figure 3It can be concluded from the infrared absorption spectrum that the product prepared in Example 7 is (R)-2-(4-chloro-2-methylphenoxy)propionic acid isooctyl ester containing an ether group.

[0126] like Figure 4 As shown in the infrared absorption spectrum of (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester, (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester has a peak at 1000 cm -1 ~1300cm -1 The position has an infrared absorption peak unique to ether bonds, namely at 1142cm -1 、1244.8cm -1 (Ar-OR) and 1755cm -1 There is an infrared characteristic absorption peak at (-COO-). Figure 5 As shown, the PEG structural unit in the compound (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester is -CH2CH2O-, and the molecular weight is 44.052. A series of polymer ion peaks are detected in the sample, and the molecular weights of adjacent polymer units differ by 44Da, indicating that the obtained product is (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester containing polyethylene glycol structural units. Among them, the difference of the characteristic peaks at 692 to 694 is 2, indicating that there are two chlorine atoms in the compound of Example 21, that is, both ends of the PEG segment in the (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester are connected to 2-(4-chloro-2-methylphenoxy) propionic acid groups, and the total molecular weight is 560, 740 to 782, which is the same as the calculated molecular weight, that is, it includes the structures shown in the following formulas IX and X:

[0127]

[0128] The PEG segment in Formula IX is the group corresponding to R in Formula III. Since both ends of PEG contain hydroxyl groups, it can undergo an esterification reaction with 2-halopropionic acid to generate an ester compound with halopropionic acid groups at both ends, and then react with 4-chloro-o-cresol to obtain a compound represented by Formula IX and a small amount of Formula X. Figure 4 Infrared absorption spectrum and Figure 5 The results of the mass spectrum show that what is prepared in Example 21 of the present application is (R)-2-(4-chloro-2-methylphenoxy) propionic acid polyethylene glycol ester containing an ether group.

[0129] Test Section

[0130] 1. Determination of product yield

[0131] The weight of the reactants and products of each step of step S1 and S2 in the preparation method of Examples 1-26 was measured by weighing, and the yield of the corresponding product prepared in each example was measured by calculation.

[0132] 2. Test of root barrier effect

[0133] The (R)-2-(4-chloro-2-methylphenoxy) propionate compounds prepared in Examples 1-26 were respectively subjected to root inhibition effect tests, including: the (R)-2-(4-chloro-2-methylphenoxy) propionate compounds prepared in Examples 1-26 were respectively prepared into root inhibition agent solutions of the same concentration (4.2 mmol / L) using acetonitrile, and then the root inhibition agent solutions were added into the test box, and the amount of the root inhibition agent solutions was the same, such as Figure 6 As shown, the test box contains the site surface / top layer of the original building 8, the anti-leakage layer 7, the root barrier layer 6 (i.e., the soil layer containing the root inhibitor solution with root blocking effect), the moisture-retaining layer 5, the drainage layer 4, the filter layer 3, the planting soil layer 2 and the dense plant covering layer 1. The plant covering layer 1 uses the plant Pyracantha as the test plant. The root inhibitor solution prepared by the (R)-2-(4-chloro-2-methylphenoxy) propionate compound prepared in Example 1-26 is placed under the root of the plant Pyracantha, thereby generating growth stress from the root. The Pyracantha is continuously fertilized and watered, and a controllable temperature is maintained to keep the experimental conditions consistent except for the type of root inhibitor, so as to avoid inaccurate test results caused by insufficient water and fertilizer. The test cycle is 2 years. After the test, the planting soil layer 2 is removed to observe whether the root puncture phenomenon occurs in the test root inhibitor solution. Among them, passing the root barrier test means that the rhizomes do not puncture through the soil layer containing the root inhibitor solution, and failing the test means that the rhizomes puncture through the soil layer containing the root inhibitor solution. The results are shown in Table 3:

[0134] Table 3 Root inhibition effect of (R)-2-(4-chloro-2-methylphenoxy) propionate compounds obtained in Examples 1-26

[0135]

[0136]

[0137] The test results in Table 3 show that the (R)-2-(4-chloro-2-methylphenoxy) propionate compounds with root barrier effect obtained in Examples 1-26 can inhibit the main root system of plants from absorbing surrounding nutrients and water when used in appropriate amounts, thereby achieving the effect of inhibiting the growth of the main root and promoting the growth of lateral roots, indicating that the (R)-2-(4-chloro-2-methylphenoxy) propionate compounds with root barrier effect can be prepared according to the methods of Examples 1-26 of the present application.

[0138] The above is only a specific implementation method of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application.

Claims

1. A method for preparing a (R)-2-(4-chloro-2-methylphenoxy) propionic acid ester compound, characterized in that: include: Provide compounds with structures shown in Formula I and II: In formula I, R is selected from C1-C18 alkyl substituted or unsubstituted by hydroxyl, -(R1-O) m -R1-OH, -(R4-O-CO-O) n -R4-OH、-(R4-O-CO-OR 10 ) w -OH, -R7-O(-CO-O-(R6-O-) p ) q -R7-OH; Wherein, R1 is a C2-C4 alkylene group, and m is an integer of 4 to 28; R4 is a C3-C15 alkylene group or n is an integer from 1 to 20; R4 is a C3-C15 alkylene group, R 10 for w is an integer from 1 to 15; R6 is an isopropylidene group, R7 is a C2-C5 alkylene group, p is an integer of 1-5, and q is an integer of 5-30; In formula II, R2 is independently selected from H, Cl, Br, I, R3 is independently selected from H, Cl, Br, I, and at least one of R2 and R3 is Cl or Br or I; The compounds represented by Formula I and Formula II are reacted under esterification catalyst conditions to generate the compound represented by Formula III: In formula III, R, R2, and R3 are as defined above; The compound represented by formula III is reacted with 4-chloro-o-cresol under etherification catalyst conditions to generate the compound represented by formula IV: In formula IV, R is as defined above.

2. The preparation method according to claim 1, characterized in that: Meet any one of the following requirements: The R is selected from a C4-C18 alkyl group which is substituted or unsubstituted by a hydroxyl group; The R is selected from -(R1-O) m -R1-OH, R1 is a C2-C3 alkylene group, and m is an integer from 5 to 11; The R is selected from -(R4-O-CO-O) n -R4-OH, R4 is C5-C6 alkylene or n is an integer from 1 to 10; The R is selected from -(R4-O-CO-OR 10 ) w -OH, R4 is a C3-C15 alkylene group, R 10 for w is an integer from 4 to 10; The R is selected from -R7-O(-CO-O-(R6-O-) p ) q -R7-OH, R6 is isopropylidene, R7 is -CH2-CH(R8)-, R8 is H or methyl, p is an integer of 1 to 2, and q is an integer of 5 to 25.

3. The preparation method according to claim 1, characterized in that: The boiling point of the compound represented by formula I is less than 200° C. The compound represented by formula I reacts with the compound represented by formula II at a molar ratio of carboxyl group:hydroxyl group=1:(1.1-5).

4. The preparation method according to claim 3, characterized in that: The compound represented by formula I has a boiling point of less than 200° C. and is selected from methanol, ethanol, propanol, 1,3-propylene glycol, isopropanol, n-butanol, isobutanol, 1,4-butanediol, 2-methyl-1,3-propylene glycol, n-pentanol, isopentanol, 1,5-pentanediol, isopentanol, neopentyl glycol, n-hexanol, 1,6-hexanediol, n-heptanol, 1,7-heptanediol, octanol, isooctanol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,4-cyclohexanediol or a combination thereof.

5. The preparation method according to claim 1, characterized in that: The compound represented by formula I is a compound with a boiling point of ≥200° C. The compound represented by formula I reacts with the compound represented by formula II at a molar ratio of carboxyl group:hydroxyl group=(0.9-1):

1.

6. The preparation method according to claim 5, characterized in that: The compound of formula I with a boiling point of ≥200°C is selected from 2,2-dimethyl-1,3-propanediol, 2-ethyl-1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, n-nonanol, 2-butyl-2-ethyl-1,3-propanediol, n-decanol, 1,10-decanediol, undecanol, 1,11-undecanediol, dodecanol, 1,12-dodecanediol, tridecanol, 1 , 13-tridecyl glycol, tetradecanol, 1,14-tetradecanol, pentadecanol, 1,15-pentadecanediol, 1-hexadecanol, heptadecanol, 1-octadecyl alcohol, polyethylene glycol with a molecular weight of 200 to 600, polypropylene glycol with a molecular weight of 400 to 600, polybutylene glycol with a molecular weight of 200 to 2000, polypropylene carbonate diol with a molecular weight of 500 to 3000, polycarbonate diol with a molecular weight of 500 to 3000, or a combination thereof.

7. The preparation method according to claim 6, characterized in that: The compound represented by formula I is selected from polypropylene carbonate diol with a number average molecular weight of 500-2000, polycarbonate-1,5-pentanediol-1,6-hexanediol ester diol with a number average molecular weight of 1900-2000, and polycarbonate-1,6-hexanediol ester diol with a number average molecular weight of 1800-2200.

8. The preparation method according to claim 1, characterized in that: Meet at least one of the following requirements: The esterification catalyst is selected from p-toluenesulfonic acid, methanesulfonic acid, concentrated sulfuric acid or a combination thereof; The compound represented by formula II is selected from 2-chloropropionic acid, 2,2-dichloropropionic acid, 2-bromopropionic acid, 2,2-bromopropionic acid, and 2-iodopropionic acid.

9. The preparation method according to claim 1, characterized in that: The compound represented by formula III and the 4-chloro-o-cresol are reacted in a molar ratio of (1.1-1.3):1 under the condition of etherification catalyst.

10. The preparation method according to any one of claims 1 to 9, characterized in that: The etherification catalyst is selected from cesium carbonate, potassium carbonate, sodium carbonate, sodium bicarbonate or a combination thereof.

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