Novel cyclic diacyl peroxide as well as preparation method and application thereof

Abstract

The invention discloses a preparation method of cyclic diacyl peroxide and the prepared cyclic diacyl peroxide, the cyclic diacyl peroxide can be synthesized by corresponding acid anhydride and also can be synthesized by corresponding dicarboxylic acid compounds, raw materials involved in the preparation process are cheap and easy to obtain, the operation is simple, the yield is high, and the method is suitable for industrial production. The industrial application is very easy to realize. Meanwhile, the cyclic diacyl peroxide disclosed by the invention overcomes the problems that the existing diacyl peroxide cannot be stored for a long time and is extremely easy to explode in the storage and transportation processes, and various heterocyclic and aromatic ring compounds can be synthesized, so that the cyclic diacyl peroxide disclosed by the invention has a wide market application prospect.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis technology, specifically relating to a method for preparing a novel cyclic diacyl peroxide and the cyclic diacyl peroxide prepared therefrom, and also relating to the application of the cyclic diacyl peroxide, such as [3+2] and [4+2] cycloaddition reactions with azides, tetrazides, and pyranones. Background Technology

[0002] Organic peroxides are organic derivatives in which one or two hydrogen atoms of hydrogen peroxide are replaced by organic groups. They can be mainly divided into three categories: acyclic peroxides, hydroperoxides, and cyclic peroxides. The general formula of organic peroxides is ROO-R', where the substituents R and R' are independent, identical, or different. The reactivity and stability of organic peroxides can be directionally controlled by changing the substituents. Furthermore, since the average bond energy of the peroxy bond in organic peroxides is approximately 142 kJ·mol⁻¹, which is one of the lowest known covalent bonds, their chemical properties differ significantly from other organic compounds. Consequently, organic peroxides have wide applications in fields such as medicinal chemistry, biochemistry, food chemistry, polymer materials, and chemical production.

[0003] As an important category of cyclic peroxides, cyclic diacyl peroxides are used in organic synthesis as free radical initiators, aromatic phenolic hydroxylating agents, epoxidizing agents, and dihydroxylating agents due to their unique reaction properties. They can also participate in reactions as precursors for benzyne. Currently, common cyclic diacyl peroxides include phthaloyl peroxide (PPO) and malonyl peroxide (MPO). However, these two types of cyclic diacyl peroxides deteriorate with long-term storage and pose a potential explosion risk during transportation and storage. Therefore, these two types of phthaloyl peroxides are generally not commercially available and must be synthesized by users before use.

[0004] To date, two common synthetic methods for cyclic diacyl peroxides have been reported in the literature. The first method involves the reaction of o-diacyl chloride with sodium percarbonate in dichloromethane. This method suffers from harsh synthetic conditions, complex experimental procedures, and intolerance to most functional groups. The second method involves the reaction of substituted malonic acid with urea peroxide in methanesulfonic acid. This method has limited substrate applicability and demanding reaction conditions. Therefore, obtaining a method for synthesizing cyclic diacyl peroxides that is mild, has broad substrate applicability, and a simple preparation process is of significant synthetic application value. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for preparing cyclic diacyl peroxides and the prepared cyclic diacyl peroxides. The preparation process utilizes inexpensive and readily available raw materials, is simple to operate, and yields high output, making it highly suitable for industrial application. Furthermore, the obtained cyclic diacyl peroxides maintain a certain level of stability at 110°C, overcoming the problems of existing diacyl peroxides' inability to be stored long-term and their tendency to explode during storage and transportation. This makes them easy to preserve and commercially viable for sale. Simultaneously, the cyclic diacyl peroxides of this invention can not only be used as conventional oxidants but can also generate angle-strained cyclohexyne under ultraviolet irradiation. Through cycloaddition reactions with substrates such as azides, tetrazides, and pyranones, various heterocyclic and aromatic compounds can be synthesized. Therefore, the cyclic diacyl peroxides of this invention have broad market application prospects.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for preparing cyclic diacyl peroxides, wherein a precursor compound of a cyclic diacyl peroxide with a structure of formula (I) or (II) or (III) or (IV) or (V) or (VI) is reacted with urea peroxide or hydrogen peroxide in a solvent to obtain the cyclic diacyl peroxide of the present invention.

[0007]

[0008]

[0009] Where R 11 R 21 R 31 R 41 R 51 R 61 R 71 R 81 R 12 R 22 R 32 R 42 R 52 R 62 R 72 R 82 R 13 R 23 R 33 R 43 R 53 R 63 R 73 R 83 R 14 R 24 R 34 R 44 R 54 R 64 R74 R 84 R 15 R 25 R 35 R 45 R 55 R 65 R 75 R 85 R 16 R 26 R 36 R 46 R 56 R 66 R 76 R 86 They are independent of each other, and may be the same or different, and each is independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0010] Or R 11 R 21 R 31 R 41 R 51 R 61 R 71 R 81 R 12 R 22 R 32 R 42 R 52 R 62 R 72 R 82 R 13 R 23 R 33 R 43 R 53 R 63 R 73 R 83 R 14 R 24 R 34 R 44 R 54 R 64 R 74 R 84 R 15 R 25 R 35 R 45 R 55 R 65 R 75 R 85 R 16 R 26 R36 R 46 R 56 R 66 R 76 R 86 The two adjacent groups together with the carbon atoms they are attached to represent an optionally substituted four- to eight-membered ring.

[0011] m, m', n, n', p, and p' are independent of each other and can be any integer between 0 and 5, either the same or different.

[0012] In this invention, the compounds with the structures of formula (I), formula (III) and formula (V) are actually acid anhydrides, which are substances formed by the dehydration of adjacent carboxylic acids. Acid anhydrides are stable, easy to store and transport, and inexpensive and readily available.

[0013] The method of this invention is simple to synthesize, and the target product is obtained in the presence of the corresponding acid anhydride or carboxylic acid in the presence of urea peroxide or hydrogen peroxide. This method uses readily available and inexpensive raw materials, has high yield, and offers strong reaction controllability, eliminating the need for extreme condition control. It is highly suitable for large-scale production, providing strong support for its broad future applications.

[0014] According to a second aspect of the present invention, a cyclic diacyl peroxide prepared by the above method is provided, having the structural formula of formula (VII), (VIII), or (IX).

[0015]

[0016] Where R 18 R 28 R 38 R 48 R 58 R 68 R 78 R 88 R 19 R 29 R 39 R 49 R 59 R 69 R 79 R 89 R 110 R 210 R 310 R 410 R 510 R 610 R 710 R 810 They are independent of each other, and may be the same or different, and each is independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0017] Or R 18 R 28 R 38 R 48 R 58 R 68 R 78 R 88 R 19 R 29 R 39 R 49 R 59 R 69 R 79 R 89 R 110 R 210 R 310 R 410 R 510 R 610 R 710 R 810 The two adjacent groups together with the carbon atoms they are attached to represent an optionally substituted four- to eight-membered ring.

[0018] m”, n” and p” are independent of each other and can be any integer between 0 and 5, either the same or different.

[0019] The cyclic diacyl peroxide of this invention exhibits good stability, maintaining a certain level of stability even at 102°C, thus making it easy to store and providing a long shelf life. Furthermore, due to its strong oxidizing properties, it can participate in a variety of reactions. In addition, under ultraviolet light irradiation, the cyclic diacyl peroxide of this invention can undergo decarboxylation to generate angle-strained cyclic alkynes, which can undergo cycloaddition reactions with substrates such as azides, tetrazides, and pyranones, enabling the synthesis of various heterocyclic and aromatic compounds, demonstrating its broad commercial application value.

[0020] According to a third aspect of the invention, the invention also provides the application of the above-mentioned cyclic diacyl peroxide, specifically, the cyclic diacyl peroxide participating in cycloaddition reactions as an oxidant, an initiator, or as a cycloalkyne precursor.

[0021] Preferably, in the above applications, when the cyclic diacyl peroxide is used as an oxidizing agent, it can be used in organic synthesis to oxidize various substances. For example, it can oxidize inert alkenes to epoxides, oxidize selenide ethers to selenoketones, oxidize thioethers to sulfoxides or sulfones, and oxidize aromatic rings to phenols.

[0022] Preferably, in the above applications, when the cyclic diacyl peroxide is used as an initiator, it can be used in organic synthesis to initiate various free radical polymerizations and other free radical reactions.

[0023] Preferably, in the above applications, when the above-mentioned cyclic diacyl peroxide participates in cycloaddition reactions as a cycloalkyne precursor, it can participate in [3+2] and [4+2] cycloaddition reactions, such as in-situ cycloaddition reactions with azides, tetrazines, pyranones, diazo compounds, etc.

[0024] The cyclic diacyl peroxides of this invention exhibit superior conversion yields and substrate adaptability when used as cyclic alkyne precursors in [3+2] and [4+2] cycloaddition reactions. Furthermore, the cyclic diacyl peroxides can be used in fluid chemistry techniques to synthesize 1,2,3-triazoles, 1,2-diazines, and polysubstituted aromatic compounds on a gram-scale.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The cyclic diacyl peroxide of the present invention can be synthesized from the corresponding acid anhydride or the corresponding dicarboxylic acid compound. It has the advantages of mild conditions, wide substrate adaptability, high functional group tolerance and high yield. It also has the advantages of simple synthesis, readily available and inexpensive raw materials, strong reaction controllability and no extreme conditions. It is very suitable for large-scale production and provides strong conditions for a broad application prospect in the future.

[0027] (2) The cyclic diacyl peroxide of the present invention can generate angle-strained cyclohexyne under ultraviolet light irradiation and participate in [3+2] and [4+2] cycloaddition reactions. For example, by cycloaddition reactions with substrates such as azide, tetrazine, and pyranone, a variety of heterocyclic and aromatic ring compounds can be synthesized. It can be seen that it shows good tolerance to various small molecules, drug molecules and natural products containing different functional groups, and can achieve modification of these substances with high yield. Attached Figure Description

[0028] Figure 1 This is the TG-DSC curve of the cyclohexenyl cyclic diacyl peroxide synthesized in Example 1 of this invention;

[0029] Figure 2 This is the single-crystal diffraction structure of the cyclohexenyl ortho-diacyl peroxide synthesized in Example 1 of this invention;

[0030] Figure 3 It is the single-crystal diffraction structure of the cyclic diacyl peroxide with bridged ring structure, serial number 12 in Table 1 of this invention. Detailed Implementation

[0031] To make the technical solution and advantages of the present invention clearer and more understandable, the technical solution of the present invention will be described more clearly and completely below in conjunction with the embodiments.

[0032] Firstly, a first aspect of the present invention provides a method for preparing cyclic diacyl peroxides, wherein a precursor compound of a cyclic diacyl peroxide with a structure of formula (I) or (II) or (III) or (IV) or (V) or (VI) is reacted with urea peroxide or hydrogen peroxide in a solvent to obtain the cyclic diacyl peroxide of the present invention.

[0033]

[0034]

[0035] Where R 11 R 21 R 31 R 41 R 51 R 61 R 71 R 81 R 12 R 22 R 32 R 42 R 52 R 62 R 72 R 82 R 13 R 23 R 33 R 43 R 53 R 63 R 73 R 83 R 14 R 24 R 34 R 44 R 54 R 64 R 74 R 84 R 15 R 25 R 35 R 45 R 55 R 65 R 75 R 85 R 16 R 26 R 36 R 46 R 56 R 66 R 76 R 86They are independent of each other, and may be the same or different, and each is independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0036] Or R 11 R 21 R 31 R 41 R 51 R 61 R 71 R 81 R 12 R 22 R 32 R 42 R 52 R 62 R 72 R 82 R 13 R 23 R 33 R 43 R 53 R 63 R 73 R 83 R 14 R 24 R 34 R 44 R 54 R 64 R 74 R 84 R 15 R 25 R 35 R 45 R 55 R 65 R 75 R 85 R 16 R 26 R 36 R 46 R 56 R 66 R 76 R 86 The two adjacent groups together with the carbon atoms they are attached to represent an optionally substituted four- to eight-membered ring.

[0037] m, m', n, n', p, and p' are independent of each other and can be any integer between 0 and 5, either the same or different.

[0038] The method of this invention is simple to synthesize, and the target product is obtained in the presence of the corresponding acid anhydride or carboxylic acid in the presence of urea peroxide or hydrogen peroxide. This method uses readily available and inexpensive raw materials, has high yield, and offers strong reaction controllability, eliminating the need for extreme condition control. It is highly suitable for large-scale production, providing strong support for its broad future applications.

[0039] Preferably, in the above preparation method, the halogen is chlorine, fluorine or bromine, with chlorine being particularly preferred.

[0040] Preferably, in the above preparation method, the substituted phenyl group can be monosubstituted or polysubstituted, wherein the substituents involved in the monosubstituted or polysubstituted group can be halogens such as fluorine, chlorine or bromine; alkoxy groups; straight-chain, branched or cyclic alkyl groups composed of 1 to 6 carbon atoms such as methyl (—CH3), ethyl (—CH2CH3), propyl (—CH2CH2CH3), pentyl (—CH2CH2CH2CH2CH3), etc.

[0041] Preferably, in the above preparation method, the unsubstituted or substituted straight-chain, branched or cyclic alkyl group consisting of 1 to 18 carbon atoms is an unsubstituted or substituted (e.g., halogen-substituted, phenyl-substituted, alkoxy-substituted) straight-chain, branched or cyclic alkyl group consisting of 1 to 6 carbon atoms, more preferably an unsubstituted or substituted straight-chain, branched or cyclic alkyl group consisting of 1 to 10 carbon atoms, especially an unsubstituted or halogen-monosubstituted or polysubstituted straight-chain, branched or cyclic alkyl group consisting of 1 to 8 carbon atoms such as methyl, trifluoromethyl, ethyl, propyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, etc.

[0042] Preferably, in the above preparation method, when R 11 R 21 R 31 R 41 R 51 R 61 R 71 R 81 R 12 R 22 R 32 R 42 R 52 R 62 R 72 R 82 R 13 R 23 R 33 R 43 R 53 R 63 R 73 R 83 R 14 R 24 R34 R 44 R 54 R 64 R 74 R 84 R 15 R 25 R 35 R 45 R 55 R 65 R 75 R 85 R 16 R 26 R 36 R 46 R 56 R 66 R 76 R 86 When two adjacent groups together with the carbon atoms to which they are attached represent an optionally substituted four- to six-membered ring, the four- to eight-membered ring may be a heterocycle, such as a heterocycle optionally spaced by heteroatoms selected from O, S and N.

[0043] Preferably, in the above preparation method, when m, m', n, n', p, and p' are non-zero integers, the groups attached to the corresponding carbon atoms are independent of each other and can be the same or different. For example, when m is 1, the group R attached to the corresponding carbon atom is... 71 and R 81 They are independent of each other, and may be the same or different, each independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms; when m is 2, each of the corresponding two carbon atoms is attached to two groups R. 71 and R 81 These four corresponding groups are independent of each other and may be the same or different, each independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms; and so on, when m is 3, 4 or 5, the corresponding three, four or five carbon atoms are each connected to two groups R. 71 and R 81 Accordingly, the six, eight, and ten groups are independent of each other, may be the same or different, and are each independently selected from hydrogen, halogens, unsubstituted or substituted phenyl groups, and unsubstituted or substituted straight-chain, branched, or cyclic alkyl groups consisting of 1 to 18 carbon atoms. Similarly, when m', n, n', p, and p' are non-zero integers, the groups attached to the corresponding carbon atoms are independent of each other, may be the same or different, and are each independently selected from hydrogen, halogens, unsubstituted or substituted phenyl groups, and unsubstituted or substituted straight-chain, branched, or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0044] Preferably, in the above preparation method, the molar ratio of the precursor compound to the urea peroxide or hydrogen peroxide is 1:(0.5-5), more preferably 1:(3-4). Within this range, both high yield of cyclic diacyl peroxides can be ensured and material waste can be avoided.

[0045] Preferably, in the above preparation method, the solvent is a liquid sulfonic acid such as methanesulfonic acid (MsOH), water and / or acetonitrile, or other organic solvents such as dichloromethane, ethyl acetate, etc. Of course, other solvents can also be used, as long as the reactants can be dissolved in it and the products will not react with it.

[0046] Preferably, in the above preparation method, the concentration of the precursor compound after dissolving in the solvent is 0.1-2.5 mol / L, more preferably 0.1-2 mol / L. This concentration ensures both a high yield of the cyclic diacyl peroxide and avoids solvent waste.

[0047] Preferably, in the above preparation method, the reaction conditions are: reaction temperature from -15°C to 35°C, and reaction time from 1 to 24 hours, preferably 12 to 24 hours. When the allylic position of the partially cyclic diacyl peroxide prepared by the present invention is relatively large, the reaction rate is relatively low, and it is necessary to extend the reaction time to achieve the desired yield.

[0048] Preferably, in the above preparation method, the urea peroxide or hydrogen peroxide is first dissolved in a solvent or mixed with a solvent at 0-10°C, preferably under ice bath conditions, and then the precursor compound is added to carry out the reaction.

[0049] Particularly preferably, in the above preparation method, when hydrogen peroxide is used, an aqueous solution of hydrogen peroxide with a mass fraction of 20-40% is preferred. Hydrogen peroxide solution of this concentration is safe and stable, and can be safely transported and stored. Using hydrogen peroxide solution at this concentration can balance yield and safety of the reaction process.

[0050] Preferably, in the above preparation method, an acylation catalyst is also added to accelerate the reaction. The type and amount of the acylation catalyst are not strictly limited. Conventional amounts of commercially available acylation catalysts in the art are acceptable, such as N,N-dimethylaminopyridine (DMAP).

[0051] More preferably, in the above preparation method, the molar ratio of the acylation catalyst to the precursor compound is 1:(5-100), and particularly preferably 1:(5-60).

[0052] Preferably, in the above preparation method, a dehydrating condensing agent is also added to promote the dehydration condensation of the intermediate to generate the target peroxide. The type and amount of the dehydrating condensing agent are not strictly limited. Any commercially available dehydrating condensing agent that is commonly used in the art and is soluble in the solvent in the preparation method of the present invention can be used, such as 1,3-dicyclohexylcarbodiimide (DCC), which is easily soluble in dichloromethane.

[0053] More preferably, in the above preparation method, the molar ratio of the dehydrating agent to the precursor compound is 1:(1-5), and particularly preferably 1:(1-4).

[0054] It is important to note that in the above preparation method, the cyclic diacyl peroxide product needs to be further purified. The specific purification process depends on the specific product or preparation process and is not strictly limited. As long as the reaction solvent, water and unreacted raw materials can be removed, it is acceptable. If the prepared product is cyclohexenyl o-diacyl peroxide, it is necessary to separate, wash, remove water and finally remove the organic solvent.

[0055] It should also be noted that the various raw materials and reaction conditions in the preparation process of the cyclic diacyl peroxide of the present invention need to be specifically set for the cyclic diacyl peroxide to be prepared. The above preparation process is only a general description. Those skilled in the art can specifically adjust the above description to obtain the desired cyclic diacyl peroxide in a high yield.

[0056] The method of this invention is simple to prepare, convenient to synthesize, has a high yield, and uses abundant raw materials. It does not require extreme reaction conditions, and large-scale production can be achieved by reasonably adjusting the synthesis conditions. Furthermore, the obtained product has good stability, allowing for advance production and storage for use in other production reactions.

[0057] According to a second aspect of the present invention, cyclic diacyl peroxides prepared by the above method are provided, having the following structural formulas (VII), (VIII), and (IX).

[0058]

[0059] Where R 18 R 28 R 38 R 48 R 58 R 68 R 78 R 88 R 19 R 29 R 39 R 49 R 59 R 69 R79 R 89 R 110 R 210 R 310 R 410 R 510 R 610 R 710 R 810 They are independent of each other, and may be the same or different, and each is independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0060] Or R 18 R 28 R 38 R 48 R 58 R 68 R 78 R 88 R 19 R 29 R 39 R 49 R 59 R 69 R 79 R 89 R 110 R 210 R 310 R 410 R 510 R 610 R 710 R 810 The two adjacent groups together with the carbon atoms they are attached to represent an optionally substituted four- to eight-membered ring.

[0061] m”, n” and p” are independent of each other and can be any integer between 0 and 5, either the same or different.

[0062] The cyclic diacyl peroxide of this invention maintains a certain degree of stability at 102°C, overcoming the problems of existing diacyl peroxides being unable to be stored for a long time and being extremely prone to explosion during storage and transportation. This makes it easy to preserve, commercialize, and sell in the market.

[0063] Preferably, in the above-mentioned cyclic diacyl peroxide, the halogen is preferably chlorine, fluorine or bromine, with chlorine being particularly preferred.

[0064] Preferably, in the above-mentioned cyclic diacyl peroxide, the substituted phenyl group can be monosubstituted or polysubstituted, wherein the substituents involved in the monosubstituted or polysubstituted group can be halogens such as halogen, chlorine or bromine; alkoxy groups; straight-chain, branched or cyclic cycloalkyl groups consisting of 1 to 6 carbon atoms such as methyl (—CH3), ethyl (—CH2CH3), propyl (—CH2CH2CH3), pentyl (—CH2CH2CH2CH2CH3), etc.

[0065] Preferably, in the above-mentioned cyclic diacyl peroxide, the unsubstituted or substituted straight-chain, branched or cyclic alkyl group consisting of 1 to 18 carbon atoms is an unsubstituted or substituted (e.g., halogen-substituted, phenyl-substituted, alkoxy-substituted) straight-chain, branched or cyclic alkyl group consisting of 1 to 6 carbon atoms, more preferably an unsubstituted or substituted straight-chain, branched or cyclic alkyl group consisting of 1 to 10 carbon atoms, particularly unsubstituted or halogen-monosubstituted or polysubstituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 8 carbon atoms such as methyl, trifluoromethyl, ethyl, propyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, etc.

[0066] Preferably, in the above-mentioned cyclic diacyl peroxide, when R 18 R 28 R 38 R 48 R 58 R 68 R 78 R 88 R 19 R 29 R 39 R 49 R 59 R 69 R 79 R 89 R 110 R 210 R 310 R 410 R 510 R 610 R 710 R 810 When two adjacent groups together with the carbon atoms to which they are attached represent an optionally substituted four- to six-membered ring, the four- to eight-membered ring may be a heterocycle, such as a heterocycle optionally spaced by heteroatoms selected from O, S and N.

[0067] Preferably, in the above-mentioned cyclic diacyl peroxides, when m”, n”, and p” are non-zero integers, the groups attached to the corresponding carbon atoms are independent of each other and may be the same or different. For example, when m” is 1, the group R attached to its corresponding carbon atom is... 71 and R 81They are independent of each other, and may be the same or different, each independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms; when m” is 2, each of its two corresponding carbon atoms is attached to two groups R. 78 and R 88 These four corresponding groups are independent of each other and may be the same or different, each independently selected from hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms; and so on, when m” is 3, 4 or 5, then the corresponding three, four or five carbon atoms are each connected to two groups R. 78 and R 88 Accordingly, the six, eight, and ten groups are independent of each other, may be the same or different, and are each independently selected from hydrogen, halogens, unsubstituted or substituted phenyl groups, and unsubstituted or substituted straight-chain, branched, or cyclic alkyl groups consisting of 1 to 18 carbon atoms. Similarly, when n” and p” are non-zero integers, the groups attached to the corresponding carbon atoms are independent of each other, may be the same or different, and are each independently selected from hydrogen, halogens, unsubstituted or substituted phenyl groups, and unsubstituted or substituted straight-chain, branched, or cyclic alkyl groups consisting of 1 to 18 carbon atoms.

[0068] Considering the preferred definition of the above-mentioned groups, the cyclic diacyl peroxides of formulas (VII), (VIII), and (IX) are selected from one of the compounds in Table 1 below:

[0069] Table 1. Structural formulas of the cyclic diacyl peroxides particularly preferred in this invention.

[0070]

[0071]

[0072]

[0073]

[0074] Spectral data of the cyclic diacyl peroxides in item 2 of Table 1 above: 1 H NMR (400MHz, Chloroform-d) δ2.97 (t, J = 7.8 Hz, 1H), 2.25 (p, J = 7.9 Hz, 1H). 13 C NMR(101MHz,Chloroform-d)δ160.53,144.78,32.00,22.18.

[0075] According to a third aspect of the invention, the application of the above-mentioned cyclic diacyl peroxide is also provided, specifically, the cyclic diacyl peroxide is used as an oxidant, an initiator, or participates in cycloaddition reactions as a cycloalkyne precursor.

[0076] Preferably, in the above applications, when the above-mentioned cyclic diacyl peroxide is used as an oxidant, it can be used in organic synthesis to oxidize selenide ethers, thioethers, double bonds, and aromatic rings. The amount and method of use are conventional choices in the field of organic synthesis and are not strictly limited.

[0077] Preferably, in the above applications, when the cyclic diacyl peroxide is used as an initiator, it can be used in organic synthesis to initiate free radical polymerization and free radical reactions. The amount and method of use are conventional choices in the field of organic synthesis and are not strictly limited.

[0078] Preferably, in the above applications, when the above-mentioned cyclic diacyl peroxide participates in cycloaddition reactions as a cycloalkyne precursor, it can participate in [3+2] and [4+2] cycloaddition reactions, such as in-situ cycloaddition reactions with azides, tetrazines, pyranones, diazo compounds, etc.

[0079] Angular-strained cyclic alkynes, where the alkyne bond is embedded in a restricted-size ring, belong to a class of reactive species that have been discovered and studied for decades. Currently, various heterocyclic compounds with different structures can be prepared through [3+2] or [4+2] cycloaddition reactions of strained cyclic alkynes with compounds such as azides and tetrazides. Of particular note is that angular-strained cyclic alkynes can simultaneously link two functional groups to two alkyne carbons, achieving "bifunctionalization" of the double bond, thus providing a solution unmatched by other methods. However, neither cyclohexynes nor their heteroatom-containing angular-strained cyclic alkynes have received much attention, despite their great potential in the synthesis of cyclohexene compounds. Furthermore, the functional groups at the other four positions besides the triple bond active site of cyclohexynes are equally important, as multi-substituted cyclohexane structural patterns are prevalent in natural products, pharmaceuticals, and bioactive molecules. Therefore, seeking readily functionalizable sites on the ring represents a significant opportunity related to cyclohexyne chemistry. Therefore, the cyclic diacyl peroxide of this invention generates angle-strained cyclic alkyne precursors under ultraviolet light, and the introduction of various substituents / functional groups on the inactive sites of the cyclohexyne precursor is of great research value.

[0080] Specifically, azide compounds refer to compounds containing an azide group (-N3), with the general formula R(N3)x, where R represents almost any metal atom, hydrogen atom, halogen atom, ammonium group (NH4), and organic group (such as methyl, phenyl, acyl, etc.). Cycloaddition reactions of azide compounds typically proceed via an electrophilic addition mechanism. In this reaction, the azide compound acts as an electrophile and reacts with a substrate containing an unsaturated bond. The azide group of the azide compound forms a new covalent bond with the carbon atom in the unsaturated bond, while the functional group of another carbon atom forms a new covalent bond with the nitrogen atom on the azide group, thus forming a cyclic product. The constructed nitrogen-containing heterocyclic compounds have significant applications in drug synthesis and materials science, attracting widespread attention from organic chemists and showing excellent application prospects. However, in the traditional cycloaddition reaction of azide compounds, namely the Huisgen cyclization reaction, high temperatures (or pressures) are required to obtain a reasonable reaction rate, thus limiting the application of this reaction in biological systems. To address this obstacle, Sharpless and his collaborators in the United States successfully overcame it by developing copper(I)-catalyzed azidocycloaddition reactions (called "click" chemistry (CuAAC)). These click reactions can proceed rapidly at physiological temperatures and in biologically rich environments, achieving selective modification of viral particles, nucleic acids, and proteins from complex tissue lysates. Unfortunately, the forced use of copper catalysts is toxic to both bacterial and mammalian cells, limiting applications requiring cell viability. Recently, catalytically uncatalyzed Huisgen cycloaddition reactions of alkynes activated by electron-attracting substituents have been reported to occur at room temperature, but these compounds are susceptible to Michael reactions with biological nucleophiles. Based on the shortcomings of existing azidocycloaddition methods, in 2004, Carolyn R. Bertozzi and colleagues utilized cyclic alkynes, particularly highly stressed cyclooctane, as a solution to replace CuAAC in biological systems. This 1,3-bipolar cycloaddition was named stress-promoted azido-alkyne cycloaddition (SPAAC). Bertozzi and his team were able to demonstrate that the biotinylated cyclooctane structure and various aliphatic azides proceeded as expected under mild conditions in acetonitrile or a mixture of acetonitrile and phosphate buffer solutions. However, the problem of low reaction rates at the concentrations used led to the design of a novel masked cyclic alkyne precursor. The ability of this precursor to generate strained cyclic alkynes under photoexcitation and thus achieve azidocycloaddition has become an important goal for researchers.

[0081] For the cyclic diacyl peroxide of this invention, extensive data have demonstrated that it decarboxylates under ultraviolet light to generate angle-strained cyclic alkynes, unlike existing precursors which rely on fluoride salts, strong bases, organometallic reagents, and heating to produce cyclic alkyne intermediates. Furthermore, the cyclic alkynes produced by this invention can undergo cycloaddition reactions in situ with various azide compounds, exhibiting good tolerance to azide compounds containing different functional groups. In addition, the reaction conditions for the cyclic diacyl peroxide of this invention with azide compounds are mild, with high rates and yields; some products achieve yields as high as 99%, demonstrating excellent application value, as detailed in Table 2.

[0082] Table 2 shows the results of [3+2] cycloaddition reactions with some azide compounds.

[0083]

[0084]

[0085]

[0086] In Table 2, the conditions for the cycloaddition reaction between cyclic diacyl peroxides and azide compounds are all 1,2-dichloroethane solvent and irradiated at 350 nm for 2 hours.

[0087] Table 3 shows the results of [3+2] cycloaddition with another group of azide compounds.

[0088]

[0089]

[0090]

[0091] In Table 3, the conditions for the cycloaddition reaction between cyclic diacyl peroxides and azide compounds are all 1,2-dichloroethane solvent and irradiation at 350 nm for 2 hours.

[0092] Specifically, tetrazine compounds are nitrogen-containing cyclic compounds with four nitrogen atoms. They acquire energy through their high positive enthalpy of formation, exhibiting excellent properties such as high energy, low sensitivity, easy attainment of oxygen balance, and environmental friendliness. They are a new class of energetic materials with promising applications that have emerged in recent years. In particular, tetrazine compounds can undergo a "cycloaddition" reaction with molecules containing alkyne functional groups, typically known as a tetrazine-alkyne cycloaddition reaction. This reaction is highly efficient and exhibits rapid kinetics, thus holding important applications in biolabeling, drug delivery, and chemical synthesis. The cyclic diacyl peroxide of this invention, under ultraviolet light irradiation, decarboxylates to form angle-strained cyclic alkynes, enabling it to undergo cycloaddition reactions with various tetrazine compounds. It also demonstrates good tolerance to various tetrazine compounds containing different functional groups, with mild reaction conditions, high rates and yields, and some products achieving yields as high as 96%, exhibiting excellent application value (see Table 4 for details).

[0093] Table 4 shows the results of the [3+2] cycloaddition reactions with tetrazine compounds.

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100] The reaction conditions for the cycloaddition reactions of cyclic diacyl peroxides with various tetrazine compounds in Table 4 are: 2 hours of illumination at a wavelength of 254 nm in acetonitrile (MeCN) solvent.

[0101] Specifically, pyranone compounds are a class of organic compounds containing a pyran ring structure. They are six-membered oxygen-containing heterocyclic compounds that can participate in various organic synthesis processes and possess pharmaceutical activity. Therefore, they are widely used in the fields of medicine, pesticides, fuels, and energy, exhibiting multiple functions such as anti-infection, anti-inflammation, insecticidal and bactericidal effects, and energy conversion, making positive contributions to the development of related fields. The cyclic diacyl peroxide of this invention, under ultraviolet light irradiation, decarboxylates to generate angle-strained cyclic alkynes, which can also undergo cycloaddition reactions with various pyranone compounds. It also shows good tolerance to various pyranone compounds containing different functional groups, with mild reaction conditions, high rates and yields, and some products achieving yields as high as 90%, demonstrating excellent application value, as detailed in Table 5.

[0102] Table 5 Results of the [4+2] cycloaddition reaction with pyranone

[0103]

[0104]

[0105]

[0106] The reaction conditions for the cycloaddition reactions of cyclic diacyl peroxides with various pyranones in Table 5 are: irradiation at 350 nm wavelength for 2 hours in MeCN solvent.

[0107] Table 6. Results of [4+2] cycloaddition reactions with pyranone compounds containing isomerization products.

[0108]

[0109]

[0110]

[0111] The reaction conditions for the cycloaddition reactions of cyclic diacyl peroxides with various pyranones in Table 6 are: irradiation with 350 nm light in MeCN solvent for 2 hours.

[0112] In recent years, the study of angle-strained cyclic alkynes precursors has received increasing attention, with various new types of precursors constantly emerging. However, these precursors either require conditions such as fluoride salts, strong bases, organometallic reagents, or heating to generate cyclic alkyne intermediates, or have relatively long synthetic routes, resulting in low overall yields. Alternatively, the synthesis process may require the use of highly hazardous reagents such as n-butyllithium and trifluoromethanesulfonic anhydride, which limits the widespread application of angle-strained cyclic alkynes in medicinal chemistry, natural product synthesis, and the post-functionalization of complex molecules. However, the cyclic diacyl peroxide of this invention can be prepared in one step from commercially available raw materials under relatively mild conditions, and can be decarboxylated under ultraviolet light to generate angle-strained cyclic alkynes, which then undergo in-situ cycloaddition reactions with azides, tetrazides, pyranones, diazo compounds, etc. This demonstrates that the cyclic diacyl peroxide of this invention exhibits good functional group tolerance to various small molecules, drug molecules, and natural products containing different functional groups. It is evident that the synthesis method and the synthesized product of this invention have broad application prospects.

[0113] Synthesis Examples

[0114] Synthesis Example 1: Synthesis of Cyclohexenyl o-diacyl peroxide from 3,4,5,6-tetrahydrobenzoic anhydride

[0115] 4 mL of methanesulfonic acid (MsOH) was added to a 25 mL round-bottom flask. 1128 mg of urea peroxide (UHP, 4.0 equivs, 12.0 mmol) was added under ice bath conditions. After complete dissolution, 608 mg of 3,4,5,6-tetrahydrobenzoic anhydride (1.0 equivs, 4.0 mmol) was added to the solution. The reaction system was then heated to room temperature and stirred for 12 h. After the reaction was complete, 10 g of ice and 10 mL of ethyl acetate were added to the reaction system. The aqueous phase was then separated using a separatory funnel, and the water was extracted three times with 10 mL of ethyl acetate. The organic phases were then combined and washed successively with 10 mL of saturated brine, 10 mL of saturated NaHCO3 solution, and 10 mL of saturated brine. The organic phase was then dried using anhydrous sodium sulfate and evaporated to dryness using a rotary evaporator (with the water bath temperature at room temperature). Finally, the residual solvent was removed under high vacuum using a diaphragm pump to obtain the product. The yield is shown in Table 1 above. The reaction equation for the entire reaction is shown below:

[0116]

[0117] The structure of this compound was determined by proton and carbon NMR spectra, and the data are as follows:

[0118] 1H NMR (400MHz, Chloroform-d) δ2.97 (t, J = 7.8Hz, 1H), 2.25 (p, J = 7.9Hz, 1H).

[0119] 13C NMR (101MHz, Chloroform-d) δ160.53, 144.78, 32.00, 22.18.

[0120] The single-crystal structure further specified the structure; see [link to relevant documentation]. Figure 2 .

[0121] TG-DSC analysis of the obtained cyclohexenyl cyclic diacyl peroxide revealed that the compound is stable below 100°C, exhibiting almost no thermal decomposition. However, above 100°C, the peroxide begins to decompose slowly. Above 130°C, the decomposition accelerates, gradually leveling off at 160°C. With further temperature increases, the residue after peroxide decomposition continues to slowly decompose until complete decomposition. Clearly, the cyclohexenyl cyclic diacyl peroxide prepared in this invention possesses good stability and participates in various reactions in its pure form. Therefore, the cyclic diacyl peroxide of this invention has promising applications and will usher in a new era in cycloaddition reactions.

[0122] Synthesis Example 2: Synthesis of Cyclohexenyl o-diacyl peroxide from 3,4,5,6-tetrahydrobenzoic anhydride

[0123] 4 mL of methanesulfonic acid and 4 mL of dichloromethane (DCM) were added to a 25 mL round-bottom flask. 1128 mg of urea peroxide (4.0 equivs, 12.0 mmol) was added under ice bath conditions. After complete dissolution, 608 mg of 3,4,5,6-tetrahydrobenzoic anhydride (1.0 equivs, 4.0 mmol) was added to the solution. The reaction system was then heated to room temperature and the reaction continued for 12 h. After the reaction was complete, 10 g of ice and 10 mL of ethyl acetate were added to the reaction system. The aqueous phase was then separated using a separatory funnel, and the water was extracted three times with 10 mL of ethyl acetate. The organic phases were then combined and washed sequentially with 10 mL of saturated brine, 10 mL of saturated NaHCO3 solution, and 10 mL of saturated brine. The organic phase was then dried using anhydrous sodium sulfate and evaporated to dryness using a rotary evaporator (with the water bath temperature at room temperature). Finally, the residual solvent was removed under high vacuum using a diaphragm pump to obtain the product. The yield is shown in Table 1 above. The reaction equation for the entire reaction is as follows:

[0124]

[0125] The reaction process took place in a solution of methanesulfonic acid and dichloromethane. The structure of the product was determined by 1H and 1C NMR spectroscopy, and the specific data were consistent with those of Synthesis Example 1.

[0126] The single-crystal structure was further specified, and the structure was the same as that prepared in Synthesis Example 1.

[0127] Synthesis Example 3: Synthesis of Cyclohexenyl o-diacyl peroxide from 3,4,5,6-tetrahydrobenzoic acid

[0128] 8 mL of dichloromethane (DCM), 4-dimethylpyridine (DMAP, 0.6 mmol, 73 mg), 1 mL of 30% hydrogen peroxide (w / v), and 6 mmol of 3,4,5,6-tetrahydrobenzoic acid were added to a 25 mL round-bottom flask to form a homogeneous solution, which was then cooled to -15 °C. Subsequently, 6.72 mmol of 1,3-dicyclohexylcarbodiimide (DCC) was added to the solution, and the reaction was continued at -15 °C for 1.5 h. After the reaction was complete, 15 mL of DCM was added to the reaction system, and the mixture was filtered through a short silica gel sieve, while simultaneously washing the sieve with 40 mL of dichloromethane. The combined solution was then concentrated under vacuum in a rotary evaporator at a water bath temperature of 15 °C, and then purified by silica gel column chromatography to obtain cyclohexenyl o-diacyl peroxide, with yields shown in Table 1 above. The reaction equation for the entire reaction is as follows:

[0129]

[0130] The reaction process takes place in a solution of methanesulfonic acid and dichloromethane. The structure of the product is determined by 1H and 1C NMR spectra, and the specific data are consistent with those of the synthesis example 1.

[0131] The single-crystal structure was further specified, and the structure was the same as that prepared in Synthesis Example 1.

[0132] In addition, this invention also synthesized cyclic diacyl peroxides numbered 1 and 3-23 in Table 1, with yields exceeding 70%, and some even reaching as high as 99%. The preparation methods were not significantly different from those in Example 1 above, differing only in the precursor compounds required for the prepared cyclic diacyl peroxides. It should also be noted that those skilled in the art can adjust the parameters in the preparation process based on the above description and the specific characteristics of the cyclic diacyl peroxides to more effectively prepare them.

[0133] Application Examples

[0134] The cyclic diacyl peroxide synthesized in the present invention can be decarboxylated under ultraviolet light to generate angle-strained cyclic alkynes. Unlike existing precursors, it does not require conditions such as fluoride salts, strong bases, organometallic reagents, and heating to generate cyclic alkyne intermediates. Furthermore, the cyclic alkynes generated by the present invention can undergo cycloaddition reactions in situ with various azides, tetrazine compounds, and pyranone compounds. Specific results are shown in Tables 2-6 above, and the specific experimental procedures are as follows.

[0135] Application Example 1: [3+2] cycloaddition reaction of cyclic diacyl peroxides with azides

[0136] The cyclic diacyl peroxide (0.2 mmol, 1 equivalent) from Table 1 and the corresponding azide compounds (0.6 mmol, 3 equivalents) from Tables 2 and 3 of this invention were added to 20 mL quartz tubes, and three vacuum / argon backfill cycles were performed. Then, 5 mL of 1,2-dichloroethane (DCE) solvent was added, and the reaction mixture was stirred at room temperature for 2 hours under UV-A light irradiation (350 nm). After the reaction was completed, the solvent was removed under reduced pressure to obtain the crude product. The crude product was purified by rapid column chromatography on silica gel (230-400 mesh) using hexane / EA as the eluent to obtain the desired product. The corresponding reactants, products, and yields are shown in Tables 2 and 3.

[0137] The present invention provides a method for the in-situ cycloaddition reaction of cyclic alkynes generated by cyclic diacyl peroxides under ultraviolet light with various azide compounds. This method shows good tolerance to various azide compounds containing different functional groups, and the reaction conditions are mild with high rates and yields. The yield of some products is as high as 99%, which has excellent application value.

[0138] Application Example 2: [4+2] cycloaddition reaction of cyclic diacyl peroxides with tetrazine compounds

[0139] The cyclic diacyl peroxide (0.2 mmol, 1 equivalent) from Table 1 and the corresponding tetrazine compound (0.6 mmol, 3 equivalent) from Table 4 were added to 20 mL quartz tubes, respectively, and three vacuum / argon backfill cycles were performed. Then, 5 mL of acetonitrile solvent was added, and the reaction mixture was stirred at room temperature for 2 hours under ultraviolet light irradiation (wavelength: 254 nm). After the reaction was completed, the solvent was removed under reduced pressure to obtain the crude product, which was purified by rapid column chromatography on silica gel (230-400 mesh) using hexane / EA as the eluent to obtain the desired product. The corresponding reactants, products, and yields are shown in Table 4.

[0140] Clearly, the cyclic diacyl peroxide of this invention can generate strained cycloalkynes under ultraviolet light. The generated strained cycloalkynes are captured in situ by tetrazine through a cycloaddition reaction. It also shows good tolerance to various tetrazine compounds containing different functional groups. Moreover, the reaction conditions are mild, the rate and yield are high, and the yield of some products is as high as 96%, which has excellent application value.

[0141] Application Example 3: [4+2] cycloaddition reaction of cyclic diacyl peroxides with pyranone compounds

[0142] The cyclic diacyl peroxide (0.2 mmol, 1 equivalent) from Table 1 and the corresponding pyranone compounds (0.6 mmol, 3 equivalents) from Tables 5 and 6 were added to a 20 mL quartz tube, and three vacuum / argon backfill cycles were performed. Then, 10 mL of acetonitrile solvent was added, and the reaction mixture was stirred at room temperature for 2 hours under ultraviolet light (wavelength 350 nm). After the reaction was complete, the solvent was removed under reduced pressure to obtain the crude product, which was purified by rapid column chromatography on silica gel (230-400 mesh) using hexane / EA as the eluent to obtain the desired product. The corresponding reactants, products, and yields are shown in Tables 5 and 6.

[0143] The cyclic diacyl peroxide of this invention, under ultraviolet irradiation, undergoes decarboxylation to generate angle-strained cyclic alkynes, which can also undergo cycloaddition reactions with various pyranone compounds. It exhibits good tolerance to various pyranone compounds containing different functional groups, with mild reaction conditions, high rates, and high yields; some products achieve yields as high as 90%, demonstrating excellent application value (see Tables 5 and 6). Clearly, the cyclic diacyl peroxide of this invention can be synthesized from corresponding acid anhydrides or corresponding dicarboxylic acid compounds, possessing advantages such as mild reaction processes, broad substrate adaptability, high functional group tolerance, and high yields. Furthermore, the cyclic diacyl peroxide of this invention, under ultraviolet irradiation, can decarboxylate to generate angle-strained cyclic alkynes, which can then serve as cyclic alkyne precursors in [3+2] and [4+2] cycloaddition reactions, exhibiting excellent conversion yields and substrate adaptability in these cycloaddition reactions. In particular, the cyclic diacyl peroxides synthesized in this invention can be used to synthesize 1,2,3-triazoles, 1,2-diazines, and polysubstituted aromatic ring compounds on a gram-scale using fluid chemistry techniques. Furthermore, the cyclic diacyl peroxides of this invention exhibit good stability, overcoming the shortcomings of existing diacyl peroxides, such as the risk of explosion and the lack of commercially available products for on-the-spot preparation. This enables large-scale commercial applications and will make a significant contribution to the development of subsequent cycloaddition reactions.

[0144] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. A process for the preparation of cyclic diacyl peroxides, characterized in that, The precursor compounds of the cyclic diacyl peroxides of the structure of formula (I) or (II) or (III) or formula (IV) or formula (V) or (VI) are reacted with urea peroxide or hydrogen peroxide in a solvent to obtain the cyclic diacyl peroxides of the present invention, wherein R11, R21, R31, R41, R51, R61, R71, R81, R12, R22, R32, R42, R52, R62, R72, R82, R13, R23, R33, R43, R53, R63, R73, R83, R14, R24, R34, R44, R54, R64, R74, R84, R15, R25, R35, R45, R55, R65, R75, R85, R16, R26, R36, R46, R56, R66, R76, R86, independently of each other, can be the same or different and are each independently selected from the group consisting of hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms, or two adjacent groups from R11, R21, R31, R41, R51, R61, R71, R81, R12, R22, R32, R42, R52, R62, R72, R82, R13, R23, R33, R43, R53, R63, R73, R83, R14, R24, R34, R44, R54, R64, R74, R84, R15, R25, R35, R45, R55, R65, R75, R85, R16, R26, R36, R46, R56, R66, R76, R86, together with the carbon atoms to which they are attached, represent an optionally substituted four- to eight-membered ring, m, m', n, n', p and p', independently of each other, can be the same or different and are any integer between 0 and 5.

2. The method of claim 1, wherein, The halogen is preferably chlorine, fluorine or bromine, particularly preferably chlorine.

3. The method of claim 1, wherein, The substituted phenyl groups can be mono- or polysubstituted, wherein the substituents involved in the mono- or polysubstitution can be halogen; alkoxy; straight-chain, branched or cyclic cycloalkyl groups consisting of 1 to 6 carbon atoms.

4. The method of claim 1, wherein, The unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 18 carbon atoms are unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 6 carbon atoms, more preferably unsubstituted or substituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 10 carbon atoms, in particular unsubstituted or halogen mono- or polysubstituted straight-chain, branched or cyclic alkyl groups consisting of 1 to 8 carbon atoms.

5. The method of claim 1, wherein, When two adjacent groups among R11, R21, R31, R41, R51, R61, R71, R81, R12, R22, R32, R42, R52, R62, R72, R82, R13, R23, R33, R43, R53, R63, R73, R83, R14, R24, R34, R44, R54, R64, R74, R84, R15, R25, R35, R45, R55, R65, R75, R85, R16, R26, R36, R46, R56, R66, R76, R86, together with the carbon atoms to which they are attached, represent an optionally substituted four- to six-membered ring, the four- to eight-membered ring can be a heterocycle, such as a heterocycle which is optionally interrupted by a heteroatom selected from the group consisting of O, S and N.

6. The method of claim 1, wherein, The molar ratio of the precursor compound to the urea peroxide or hydrogen peroxide is 1 : (0.5-5), more preferably 1 : (3-4).

7. The method of claim 1, wherein, When m, m', n, n', p and p' are integers other than 0, the groups attached to the respective carbon atoms are, independently of one another, the same or different.

8. The method of claim 1, wherein, The concentration of the precursor compound after it is dissolved in the solvent is 0.1-2.5 mol / L, more preferably 0.1-2 mol / L.

9. A cyclic diacyl peroxide prepared by the process of claims 1-8, characterized in that, the formula (VII), the formula (VIII) or the formula (IX), wherein R 18 , R 28 , R 38 , R 48 , R 58 , R 68 , R 78 , R 88 , R 19 , R 29 , R 39 , R 49 , R 59 , R 69 , R 79 , R 89 , R 110 , R 210 , R 310 , R 410 , R 510 , R 610 , R 710 , R 810 are independent of each other, can be identical or different and are each independently selected from the group consisting of hydrogen, halogen, unsubstituted or substituted phenyl, unsubstituted or substituted straight-chain, branched or cyclic alkyl consisting of 1 to 18 carbon atoms, or R 18 , R 28 , R 38 , R 48 , R 58 , R 68 , R 78 , R 88 , R 19 , R 29 , R 39 , R 49 , R 59 , R 69 , R 79 , R 89 , R 110 , R 210 , R 310 , R 410 , R 510 , R 610 , R 710 , R 810 two groups adjacent to each other represent, together with the carbon atoms to which they are attached, an optionally substituted four- to eight-membered ring, m", n" and p", independently of one another, are the same or different and are any integer between 0 and 5.

10. The use of a cyclic diacyl peroxide according to claim 9, characterized in that The cyclic diacyl peroxide participates in a cycloaddition reaction as oxidizing agent, initiator or as cyclopropene precursor.

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