CN108017558B

CN108017558B - Preparation method of anisyl nitrile

Info

Publication number: CN108017558B
Application number: CN201810050598.3A
Authority: CN
Inventors: 程卫习; 鲍瑞雪; 范思源; 刘迎; 郑艺; 樊洪波; 谷彦彬; 郝亚楠; 赵荣荣; 王晓君; 王颖颖; 魏克明; 王福; 程宇洁; 薛沛
Original assignee: Henan Luoyang Hydrology And Water Resources Survey Bureau
Current assignee: Henan Luoyang Hydrology And Water Resources Survey Bureau
Priority date: 2018-01-18
Filing date: 2018-01-18
Publication date: 2020-06-05
Anticipated expiration: 2038-01-18
Also published as: CN108017558A

Abstract

The invention relates to a method for preparing anisyl nitrile, which comprises the steps of dissolving p-methoxy anisole and ammonium acetate in glacial acetic acid, introducing oxygen, adding a mixture of nitric acid/tetramethyl piperidine nitrogen oxide as a catalyst, sealing a reactor, and reacting at the temperature of 30-120 ℃ for 2-30h to obtain the anisyl nitrile. The preparation method of the invention uses the ether compound as the raw material and oxygen as the oxidant, thus reducing the production cost and reducing the environmental pollution.

Description

Preparation method of anisyl nitrile

Technical Field

The invention relates to the technical field of chemical raw material preparation, and particularly relates to a preparation method of anisyl nitrile.

Background

The anisic nitrile, also called as p-methoxy benzonitrile, has strong fragrance and small irritation to skin, and is not only widely applied to flavoring materials and water quality analysis reagents. But also for the preparation of a range of chemicals. The current method for synthesizing the anisic nitrile mainly comprises the following steps. (1) Anisic aldehyde method. The method takes anisic aldehyde as a reaction raw material, generates anisic aldoxime by reacting with hydroxylamine hydrochloride, and then obtains the anisic nitrile product by dehydration of the aldoxime. This process has some disadvantages such as low conversion and complicated purification process. (2) P-methoxytoluene. The method takes p-methoxytoluene as a raw material, and prepares an anisic nitrile product in one step by ammoniation oxidation of methyl under the catalysis of metal oxides such as V/Ti, V/MO, V/Sb or V/Sn. The method uses cheap raw materials, but has high requirements on the catalyst, and the reaction temperature is as high as 400 DEG^oAnd C is higher than the C. (3) P-methoxyaniline method. The method takes p-anisidine as a raw material, firstly carries out diazotization of amino, and then reacts with cyanide to generate the anisidine. The method has high yield and mild reaction conditions, but the use of the highly toxic cyanide is a main disadvantage in industrial application. (4) In addition, the literature reports that p-methoxy halogenated benzene, p-methoxy benzamide or p-methoxy acetophenone can be used as raw materials to synthesize the anisyl nitrile. These processes generally have a high cost of reaction raw materials and catalysts and a low potential for industrial application.

Disclosure of Invention

The invention aims to solve the technical problems, provides a method for preparing the anisidine, and solves the problem of high comprehensive cost caused by the use of metal catalysts or dangerous reaction reagents and the like in the conventional method.

In order to solve the technical problems, the invention adopts the technical scheme that: a preparation method of anisyl nitrile comprises the steps of dissolving 4-methoxy benzyl methyl ether and ammonium acetate in glacial acetic acid, introducing oxygen, adding a mixture of nitric acid/tetramethyl piperidine nitrogen oxide as a catalyst, sealing a reactor, and reacting at 30-120 ℃ for 2-30h to obtain the anisyl nitrile.

The structural formula of the anisyl nitrile is as follows:

；

the synthetic route is as follows:

；

the preparation method of the anisidine of the invention is further optimized as follows: the pressure of the oxygen is 0.5-5 MPa.

The preparation method of the anisidine of the invention is further optimized as follows: the mass ratio of the ammonium acetate to the 4-methoxybenzyl methyl ether is 1-4: 1.

The preparation method of the anisidine of the invention is further optimized as follows: the ratio of the amount of the nitric acid to the amount of the 4-methoxybenzyl methyl ether substance is 0.3-1:1, and the ratio of the amount of the tetramethylpiperidine nitroxide to the amount of the 4-methoxybenzyl methyl ether substance is 0.3-1: 1.

Advantageous effects

(1) The preparation method of the invention uses the ether compound as the raw material and oxygen as the oxidant, thus reducing the production cost and reducing the environmental pollution.

(2) The product prepared by the method has high purity and high conversion rate of raw materials, effectively improves the product quality and reduces the production cost.

Drawings

FIG. 1 is a schematic representation of the product of example 1, Anisonile¹H-NMR images.

FIG. 2 is a schematic representation of the product of example 1, Anisonile¹³C-NMR chart.

Detailed Description

The technical solution of the present invention is further described below with reference to specific embodiments.

Example 1

Magnetons, 2 mL of glacial acetic acid, 0.5mmol of 4-methoxybenzyl methyl ether, 1.5mmol of ammonium acetate, 0.3mmol of nitric acid and 0.2mmol of tetramethylpiperidine nitroxide are sequentially added into a high-pressure reaction kettle with a polytetrafluoroethylene lining. After the reaction kettle is sealed, 4MPa of oxygen is filled, the reaction kettle is placed in a heating tank at the temperature of 50 ℃, and the reaction kettle reacts for 20 hours under the magnetic stirring. Once the reaction time was reached, the reaction was cooled to room temperature and the product was quantitatively analyzed by internal standard analysis using a gas chromatograph to give a 91% yield of the anisonitrile product. And then repeating the experiment, and separating and purifying the product by a column chromatography separation method to obtain the anisidine product. By using¹H-NMR、¹³The structure of the product is determined by C-NMR as shown in FIGS. 1 and 2.

Examples 2 to 9

The oxygen pressure in example 1 was changed to 0.5MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 4MPa, 5MPa, and the other conditions were not changed, whereby the yields (internal gaseous standards) of the products were 62%, 85%, 82%, 86%, 87%, 90%, 91%, and 87%, respectively.

Examples 10 to 14

The amounts of ammonium acetate in example 1 were changed to 0.5mmol, 0.75mmol, 1mmol, 1.5mmol, and 2mmol, and the other conditions were not changed, whereby the yields of the products (gas phase internal standards) were 40%, 52%, 81%, 91%, and 86%, respectively.

Examples 15 to 22

The amounts of nitric acid substance in example 1 were changed to 0.15mmol, 0.2mmol, 0.25mmol, 0.3mmol, 0.35mmol, 0.4mmol, 0.45mmol, and 0.5mmol, and the other conditions were not changed, whereby the yields (gas phase internal standards) of the products were 21%, 62%, 85%, 91%, 85%, 90%, 89%, and 93%, respectively.

Examples 23 to 30

The amounts of substance of tetramethylpiperidine nitroxide in example 1 were changed to 0.15mmol, 0.2mmol, 0.25mmol, 0.3mmol, 0.35mmol, 0.4mmol, 0.45mmol, and 0.5mmol, and the other conditions were not changed, whereby the yields (gas phase internal standards) of the products were 79%, 91%, 93%, 88%, 95%, 91%, 96%, and 92%, respectively.

Examples 31 to 38

The reaction temperatures in example 1 were changed to 30 ℃, 40 ℃, 50 ℃, 60 ℃, 80 ℃, 100 ℃, 120 ℃ respectively, and other conditions were not changed, and the yields of the products (gas phase internal standards) were 42%, 77%, 91%, 83%, 55%, 36%, 21%, respectively.

Examples 39 to 47

The reaction times in example 1 were changed to 2h, 4h, 7h, 10h, 13h, 16h, 20h, 25h, and 30h, respectively, and the other conditions were not changed, resulting in yields of products (gas phase internal standards) of 35%, 50%, 56%, 71%, 82%, 88%, 91%, 94%, and 86%, respectively.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A preparation method of the anisyl nitrile is characterized by comprising the following steps: dissolving 4-methoxybenzyl methyl ether and ammonium acetate in glacial acetic acid, introducing oxygen, adding a mixture of nitric acid/tetramethyl piperidine oxynitride as a catalyst, sealing a reactor, and reacting at 30-120 ℃ for 2-30h to obtain the anisic nitrile.

2. The method for preparing the anisic nitrile according to claim 1, wherein: the pressure of the oxygen is 0.5-5 MPa.

3. The method for preparing the anisic nitrile according to claim 1, wherein: the mass ratio of the ammonium acetate to the 4-methoxybenzyl methyl ether is 1-4: 1.

4. The method for preparing the anisic nitrile according to claim 1, wherein: the ratio of the amount of the nitric acid to the amount of the 4-methoxybenzyl methyl ether substance is 0.3-1:1, and the ratio of the amount of the tetramethylpiperidine nitroxide to the amount of the 4-methoxybenzyl methyl ether substance is 0.3-1: 1.