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CN-121974773-A - Preparation method of divinyl phenyl compound capable of generating alkenyl in situ

CN121974773ACN 121974773 ACN121974773 ACN 121974773ACN-121974773-A

Abstract

The invention provides a preparation method of a divinyl phenyl compound for generating alkenyl in situ, and relates to the field of organic synthesis. The preparation method comprises the steps of adding 4- (2-haloethyl) benzyl halide or a solution thereof into a reaction container containing magnesium and a solvent under an inert gas atmosphere to perform self-coupling reaction to form a first intermediate compound, adding a first alkali reagent to perform elimination reaction on the first intermediate compound, and performing post-treatment to obtain 1, 2-bis (4-vinyl) phenyl) ethane. The invention can avoid the vinyl from self-polymerization in the reaction process to the greatest extent, thereby improving the reaction yield and the product purity.

Inventors

  • LU QIAN
  • YANG ZHISHEN
  • CAO LIFENG
  • Niu Yinghui
  • HU JIANHUO
  • DENG GONGYAN

Assignees

  • 上海旭流化学科技有限公司

Dates

Publication Date
20260505
Application Date
20260202

Claims (10)

  1. 1. A method for preparing a divinyl phenyl compound capable of generating alkenyl in situ, which is characterized by comprising the following reaction formula: in the above formula, X 1 ,X 2 is independently selected from any one of Cl, br and I, The method comprises the following steps: and (3) under the inert gas atmosphere, adding the compound 1 or a solution thereof into a reaction container containing magnesium and a solvent for self-coupling reaction to form a first intermediate compound, adding a first alkali reagent to enable the first intermediate compound to undergo elimination reaction, and carrying out post-treatment to obtain the compound 2.
  2. 2. The method for producing an in situ alkenyl-generating divinylbenzene compound according to claim 1, wherein: wherein the solvent is selected from any one or more of tetrahydrofuran, 2-methyltetrahydrofuran, ethylene glycol dimethyl ether, tert-butyl methyl ether or diethyl ether.
  3. 3. The method for producing an in situ alkenyl-generating divinylbenzene compound according to claim 1, wherein: wherein the molar ratio of magnesium to compound 1 is (0.45-0.60): 1.
  4. 4. The method for producing an in situ alkenyl-generating divinylbenzene compound according to claim 1, wherein: Wherein the molar ratio of the first base reagent to the compound 1 is (0.95-1.05): 1.
  5. 5. The method for producing an in situ alkenyl-producing divinylbenzene compound according to claim 1, wherein, Wherein the first alkali reagent is selected from any one or more of potassium hydroxide, sodium hydroxide, potassium tert-butoxide, sodium tert-butoxide or sodium hydride.
  6. 6. A method for preparing a divinyl phenyl compound capable of generating alkenyl in situ, which is characterized by comprising the following reaction formula: in the above formula, X 1 ,X 2 is independently selected from any one of Cl, br and I, The method comprises the following steps: adding the compound 1 and the compound 3 into a reaction vessel containing a second alkali reagent and a solvent for alkylation reaction to form a second intermediate compound, adding a third alkali reagent to make the second intermediate compound undergo elimination reaction, carrying out post-treatment to obtain a compound 4, Wherein the second alkali reagent is sodium hydroxide or potassium hydroxide, and the third alkali reagent is potassium tert-butoxide or sodium tert-butoxide.
  7. 7. The method for producing an in situ alkenyl-producing divinylbenzene compound according to claim 6, wherein: Wherein the solvent is tetrahydrofuran, N-dimethyl sulfoxide, N-methylpyrrolidone or 1, 3-dimethyl-2-imidazolidinone.
  8. 8. The method for producing an in-situ alkenyl-producing divinylbenzene compound according to claim 1 or 6, characterized in that: Wherein the reaction is carried out at 0-80 ℃.
  9. 9. The method for producing an in-situ alkenyl-producing divinylbenzene compound according to claim 1 or 6, characterized in that: Wherein the compound 1 is Or (b) 。
  10. 10. The method for producing an in-situ alkenyl-producing divinylbenzene compound according to claim 1 or 6, characterized in that: Wherein the reaction is carried out by a one-pot method.

Description

Preparation method of divinyl phenyl compound capable of generating alkenyl in situ Technical Field The invention relates to the field of organic synthesis, in particular to a preparation method of a divinyl phenyl compound for generating alkenyl in situ. Background Symmetrical diphenyl olefine compound (such as 1, 2-bis (4-vinyl phenyl) ethane (BVPE), 9-bis (2-vinyl benzyl) -9H-fluorene (BVF) and the like) is an ideal difunctional crosslinking agent, and two vinyl groups in the molecular structure can be copolymerized with the end groups of PPO resin in a thermal or catalytic mode to form a compact and stable three-dimensional network structure. The structure not only can remarkably improve the glass transition temperature and heat resistance of the composite material, but also can hardly deteriorate the dielectric property of a resin system because the molecules are symmetrical nonpolar hydrocarbon structures, thereby perfectly meeting the requirements of high-frequency and high-speed application scenes. Chinese patent CN120117950 a reports the following 1, 2-bis (4-vinylphenyl) ethane (BVPE) route, with the following reaction formula: this route uses 4-vinylbenzyl chloride as a starting material and utilizes its own grignard reaction to produce 1, 2-bis (4-vinylphenyl) ethane. Chinese patent CN119263950 a reports the following route, the reaction formula is as follows: The method takes p-chlorobenzyl chloride as an initial raw material, and takes Wurtz coupling reaction in the presence of magnesium to form a coupling intermediate, and then the coupling intermediate is prepared into a Grignard reagent and then takes Kumada reaction with vinyl chloride to obtain 1, 2-bis (4-vinyl phenyl) ethane. Chinese patent CN 119019215A reports a synthetic route to 9, 9-bis (2-vinylbenzyl) -9H-fluorene (BVF). The route takes fluorene and 2-chloromethyl styrene as initial raw materials, and the reaction is carried out in the presence of alkali and polymerization inhibitor, thus obtaining the target product. However, the method has complex post-treatment of reaction yield, risks of self-polymerization and low reaction yield. The above methods are all synthetic routes using vinyl-containing raw materials, however paper The Mechanism of Vinyl Polymerizations（Journal of the American Chemical Society, 1937, 59(2):241-253） indicates that the activation energy for styrene autopolymerization is only 32 kcal/mol, and according to Arrhenius' formula, styrene spontaneously polymerizes even at room temperature without a catalyst, and the reaction rate increases exponentially with increasing temperature. Paper "study of thermal polymerization Properties of divinylbenzene" (Fine petrochemical engineering, 2022 (005): 039.) "further states that divinylbenzene compounds undergo significant autopolymerization above 70 ℃. Under the condition of 90 ℃, the self-polymerization rate can reach 7% only by 30 min. Therefore, when vinyl-containing materials are used as reaction raw materials, the materials can undergo self-polymerization in the reaction process, so that the reaction yield is reduced, and the purification difficulty is greatly increased and the product purity is reduced because the properties of the self-polymerized products are similar to those of target products. Furthermore, according to the experimental study of the applicant, when Kumada reaction is performed in the method reported in chinese patent CN119263950 a, a large amount of coupling byproducts which are difficult to purify are generated under the action of transition metal catalyst, which also makes industrial production difficult. Especially, in the production of hundred gram grade and above, the coupling by-product can reach more than 5 percent, which has great influence on industrial production. Disclosure of Invention The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for preparing a divinylbenzene-based compound in situ, which can generate a styryl group in situ so as to minimize self-polymerization of the styryl group in the reaction process, thereby effectively reducing side reactions, and improving reaction yield and product purity. The present invention provides two sets of technical schemes based on in situ generation of an alkenyl divinyl phenyl compound, wherein the first set can be used for preparing 1, 2-bis (4-vinyl phenyl) ethane (BVPE) and the second set can be used for preparing 9, 9-bis (2-vinyl benzyl) -9H-fluorene (BVF). The technical scheme of the preparation method of the first set of divinyl phenyl compounds for generating alkenyl in situ provided by the invention is as follows: The invention provides a method for preparing a divinyl phenyl compound for generating alkenyl in situ, which has the characteristics, The reaction formula is as follows: in the above formula, X 1,X2 is independently selected from any one of Cl, br and I, The method comprises the following step