阅读说明：本技术 一种3,6-二溴-2-甲基苯甲醛及其化学合成方法 (3, 6-dibromo-2-methylbenzaldehyde and chemical synthesis method thereof ) 是由 汤艳峰 王纯 丁津津 丁欣宇 王敏敏 王金 邹逢霞 刘维群 张梦珂 沈璐婕 徐润 于 2019-09-05 设计创作，主要内容包括：本发明涉及一种3,6-二溴-2-甲基苯甲醛的化学合成方法。本发明以3-氨基-6-溴-2-甲基苯甲酸甲酯为原料,经重氮化反应、还原反应、氧化反应等三步反应制备了3,6-二溴-2-甲基苯甲醛。为该化合物的合成提供了一种高效合成的方法。(The invention relates to a chemical synthesis method of 3, 6-dibromo-2-methyl benzaldehyde. The 3, 6-dibromo-2-methylbenzaldehyde is prepared by taking 3-amino-6-bromo-2-methylbenzoic acid methyl ester as a raw material and performing diazotization, reduction, oxidation and other three steps of reactions. Provides a high-efficiency synthesis method for the synthesis of the compound.)

1. A compound I, namely: the 3, 6-dibromo-2-methylbenzaldehyde is characterized by having a molecular formula shown as a formula 1.

2. The chemical synthesis method of the compound I as claimed in claim 1, characterized in that the compound I is synthesized by three steps of reaction by using 3-amino-6-bromo-2-methylbenzoic acid methyl ester as a raw material, and the synthetic route is shown as a formula 2.

3. The chemical synthesis process of compound i according to claim 2, comprising the following synthesis steps:

s1, adding tert-butyl nitrite into methanol, adding copper bromide, controlling the reaction temperature, adding 3-amino-6-bromo-2-methylbenzoate, and reacting for 3 hours to prepare 3, 6-dibromo-2-methylbenzoate;

s2, adding lithium aluminum hydride into tetrahydrofuran, dripping the methyl 3, 6-dibromo-2-methylbenzoate obtained in the step S1 into the tetrahydrofuran solution, controlling the reaction temperature, and reacting for 2 hours to synthesize (3, 6-dibromo-2-methylphenyl) methanol;

s3, adding the (3, 6-dibromo-2-methylphenyl) methanol obtained in the step S2 into dichloromethane, then adding manganese dioxide, controlling the reaction temperature, and carrying out reflux reaction for 12 hours to obtain the 3, 6-dibromo-2-methylbenzaldehyde.

4. A process for the chemical synthesis of compound i according to claim 3, characterized in that: the reaction temperature in the step S1 is 50-80 ℃.

5. A process for the chemical synthesis of compound i according to claim 3, characterized in that: the reaction temperature in the step S2 is-10-10 ℃.

6. A process for the chemical synthesis of compound i according to claim 3, characterized in that: the reaction temperature of the step S3 is 30-60 ℃.

Technical Field

The invention relates to 3, 6-dibromo-2-methyl benzaldehyde and a chemical synthesis method thereof.

Background

The benzaldehyde containing bromine and its derivatives are important intermediates for preparing many medicines and pesticides and organic synthesis, and often have important physiological and pharmacological activities. For example, o-bromobenzaldehyde and its derivatives are important pharmaceutical intermediates, which can be used in the synthesis of many drugs. In addition, bromobenzene is used as a fine chemical product intermediate and has wide application in the fields of catalysts, medicines, pesticides and the like. Therefore, the synthesis of the benzaldehyde containing bromine and the derivatives thereof has very important significance.

3, 6-dibromo-2-methylbenzaldehyde is an important medical intermediate, so that the compound has important practical significance for the synthesis research of the compound.

Disclosure of Invention

An object of the present invention is to provide a compound which is useful as a pharmaceutical intermediate, namely: 3, 6-dibromo-2-methylbenzaldehyde and a chemical synthesis method thereof.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a compound I, namely: the 3, 6-dibromo-2-methylbenzaldehyde is characterized by having a molecular formula shown as a formula 1.

The chemical synthesis method of the compound I is characterized in that 3-amino-6-bromo-2-methyl benzoate is used as a raw material, and the compound I is synthesized through three steps of reactions, wherein the synthetic route is shown as a formula 2.

The chemical synthesis method of the compound I is characterized by comprising the following synthesis steps:

s1, adding tert-butyl nitrite into methanol, adding copper bromide, controlling the reaction temperature, adding 3-amino-6-bromo-2-methylbenzoate, and reacting for 3 hours to prepare 3, 6-dibromo-2-methylbenzoate;

s2, adding lithium aluminum hydride into tetrahydrofuran, dripping the methyl 3, 6-dibromo-2-methylbenzoate obtained in the step S1 into the tetrahydrofuran solution, controlling the reaction temperature, and reacting for 2 hours to synthesize (3, 6-dibromo-2-methylphenyl) methanol;

s3, adding the (3, 6-dibromo-2-methylphenyl) methanol obtained in the step S2 into dichloromethane, then adding manganese dioxide, controlling the reaction temperature, and carrying out reflux reaction for 12 hours to obtain the 3, 6-dibromo-2-methylbenzaldehyde.

Further, the reaction temperature in the step S1 is 50-80 ℃.

Further, the reaction temperature in the step S2 is-10-10 ℃.

Further, the reaction temperature in the step S3 is 30 to 60 ℃.

The invention has the beneficial effects that: the chemical synthesis method provided by the invention starts from 3-amino-6-bromo-2-methylbenzoic acid methyl ester as a raw material, and synthesizes the 3, 6-dibromo-2-methylbenzaldehyde through three steps of reactions.

Drawings

FIG. 1 is a 1H-NMR spectrum of compound I prepared in example 1.

Detailed description of the invention

The following detailed description will provide specific embodiments of the present invention. These embodiments are merely illustrative and not intended to limit the scope or the principles of the invention, which is defined by the claims and includes obvious modifications and variations based thereon.