阅读说明：本技术 酸性分子筛催化烯烃环丙烷化反应的方法 (Method for catalyzing cyclopropanation reaction of olefin by acidic molecular sieve ) 是由 邹吉军 史成香 潘伦 张香文 于 2021-09-06 设计创作，主要内容包括：本发明公开了一种酸性分子筛催化烯烃环丙烷化的方法,包括如下步骤：①在-30℃～10℃和氮气氛围中,将酸性分子筛催化剂和锌类卡宾体混合；②向步骤①的反应体系中加入原料烯烃进行反应；③分离提纯步骤②的反应产物即得到环丙烷化合物。本发明采用酸性分子筛催化剂来烯烃环丙烷化反应,催化剂活性高,烯烃转化率和产物高；并且分子筛可以回收循环使用,降低了生产成本。(The invention discloses a method for catalyzing cyclopropanation of olefin by an acidic molecular sieve, which comprises the following steps: firstly, mixing an acidic molecular sieve catalyst and a zinc carbene compound at-30-10 ℃ in a nitrogen atmosphere; secondly, adding raw material olefin into the reaction system of the first step for reaction; and thirdly, separating and purifying the reaction product obtained in the second step to obtain the cyclopropane compound. The invention adopts the acidic molecular sieve catalyst to carry out cyclopropanation reaction on the olefin, and has high catalyst activity, high olefin conversion rate and high product yield; and the molecular sieve can be recycled, so that the production cost is reduced.)

1. A method for catalyzing cyclopropanation of olefin by using an acidic molecular sieve is characterized by comprising the following steps: firstly, mixing an acidic molecular sieve catalyst and a zinc carbene compound at-30-10 ℃ in a nitrogen atmosphere; secondly, adding raw material olefin into the reaction system of the first step for reaction; and thirdly, separating and purifying the reaction product obtained in the second step to obtain a cyclopropanation product.

2. The method of claim 1, wherein the acidic molecular sieve catalyst is one or more of HZSM-5, H β, HY, Al-MCM-41.

3. The method of claim 1 or 2, wherein the acidic molecular sieve catalyst is used in an amount of 10 to 70 wt% of the feedstock olefins.

4. The method of claim 1, wherein the zinc-based carbene is EtZnCH₂I。

5. The method according to claim 1 or 4, wherein the ratio of the raw material olefin to the zinc-based carbene is 1 (1-6).

6. The method according to claim 1, wherein the olefin is one or more of myrcene, alpha-pinene, beta-pinene, dicyclopentadiene, norbornene, norbornadiene.

Technical Field

The invention relates to the technical field of cyclopropanation of olefin, in particular to a method for catalyzing cyclopropanation of olefin by using an acidic molecular sieve catalyst.

Background

With the rapid development of the aerospace industry, higher requirements are also put forward on the performance of aerospace fuels, and the preparation of aerospace fuels with high specific impulse and high energy density is necessary. The specific impulse and density of the fuel can be effectively improved by introducing a high-tension ring structure into the fuel molecules. The Simmons-Smith reaction, one of the effective means to introduce a high-tension three-membered ring structure into fuel molecules, is widely used for synthesizing various cyclopropane compounds.

In the Simmons-Smith reaction, alkene and carbene body undergo cyclopropanation reaction and then are converted into saturated alkane, and the carbene body can be represented by the formula RZnCH₂X represents, wherein R is an organic group, and X is a halogen atom; the activity of the carbene can be changed by regulating the structure of the R group. It was found that an organic compound was added to the reaction systemAcids such as CF₃COOH or CCl₃COOH, etc., or Lewis acids such as TiCl₄、AlCl₃Or ZnCl₂And the like, the structure of the R group can be changed, the reactivity of the carbene can be improved, and the cyclopropanation reaction can be promoted. However, it is not limited toThe Acid or Lewis Acid is continuously consumed in the reaction and cannot be recycled, thereby causing a great deal of waste.

The present invention has been made to solve the above problems.

Disclosure of Invention

For solving the problems in the prior artThe invention provides a method for catalyzing cyclopropanation reaction of olefin by using recyclable acidic molecular sieve catalyst, which solves the problems that Acid or Lewis Acid is continuously consumed and cannot be recycled.

The technical scheme of the invention is as follows:

a method for cyclopropanation of an olefin catalyzed by an acidic molecular sieve comprising the steps of: firstly, mixing an acidic molecular sieve catalyst and a zinc carbene compound at-30-10 ℃ in a nitrogen atmosphere; secondly, adding raw material olefin into the reaction system of the first step for reaction; and thirdly, separating and purifying the reaction product obtained in the second step to obtain a cyclopropanation product.

Preferably, the acidic molecular sieve catalyst is one or more of HZSM-5, Hbeta, HY and Al-MCM-41.

Preferably, the dosage of the acidic molecular sieve catalyst is 10-70 wt% of the raw material olefin.

Preferably, the zinc carbene is EtZnCH₂I。

Preferably, the ratio of the raw material olefin to the zinc-based carbene is 1 (1-6).

Preferably, the olefin is one or more of myrcene, alpha-pinene, beta-pinene, dicyclopentadiene, norbornene and norbornadiene.

The invention has the beneficial effects that:

1. the invention adopts the acidic molecular sieve as the catalyst for cyclopropanation of olefin for the first time, the catalyst has high activity, and the conversion rate of olefin and the product yield are both higher than the catalytic effect of homogeneous organic acid.

2. The acidic molecular sieve catalyst can be recycled, and the activity of the catalyst is hardly reduced after the catalyst is recycled for ten times. The production cost is greatly reduced.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available by purchase.

Example 1: catalytic cyclopropanation of olefins with acidic molecular sieves

(1) Firstly, roasting the HZSM-5 molecular sieve at 550 ℃ for 5 hours to remove adsorbed impurities;

(2) at-20 ℃ and N₂Adding 30mL of diethyl zinc solution and 30mL of dichloromethane solvent into a three-neck jacketed flask under the atmosphere;

(3) weighing 0.594g of the roasted HZSM-5 molecular sieve, adding the molecular sieve into the solution in the step (2) under mechanical stirring, slowly dropwise adding 15mL of dichloromethane solvent into the solution, and reacting for 20 min;

(4) measuring 15mL of dichloromethane solvent, adding 2.470mL of diiodomethane reagent, and uniformly mixing; then dropwise adding the solution into the reaction solution obtained in the step (3) for reaction for 20 min;

(5) measuring 15mL of dichloromethane solvent, adding 2.020mL of dicyclopentadiene reaction raw material, slowly dropwise adding the dicyclopentadiene reaction raw material into the reaction liquid in the step (4), and reacting for 4 hours at 25 ℃;

(6) after the reaction is finished, adding a saturated ammonium chloride solution into the reaction solution, and continuously stirring for 5 minutes; then separating the organic phase from the aqueous phase, washing the organic phase with deionized water and saturated sodium chloride solution in turn, and drying with anhydrous magnesium sulfate; finally, the product composition was analyzed by gas chromatography. The product cyclopropanation product yield was 89.3%.

The HZSM-5 molecular sieve after the reaction of example 1 was recovered by filtration, and the reaction was repeated 10 times under the same reaction conditions as in example 1, and the reaction results are shown in table 1.

TABLE 1 catalytic Effect of HZSM-5 molecular sieves used 10 times in succession

Number of repetitions	Product yield/%
		2	88.8
3	89.5
		4	86.8
5	84.9
		6	85.3
7	86.1
		8	85.8
9	83.9
		10	84.4
11	85.6

As can be seen from Table 1, the acidic molecular sieve HZSM-5 catalyst was recovered and recycled for 10 times, and the yield of the product was very little reduced.

Examples 2 to 8

Examples 2-8 the reaction procedure was the same as in example 1 except for the reaction raw materials, catalysts or reaction conditions, as shown in Table 2.

Table 2 examples 2 to 8

As can be seen from table 2, the catalyst activity is high, the olefin conversion rate and the product yield are high, and the cyclopropane compound yield is over 85% when the acidic molecular sieve is used as the catalyst for the cyclopropanation reaction of the olefin.

While specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various changes in detail will be apparent to those skilled in the art without departing from the invention.