Preparation of benzoyl chloride from benzoic acid

Benzoyl chloride from benzoic acid: production process and application analysis

Benzoyl chloride (C6H5COCl) is an important organic compound in the chemical industry and is commonly used in the synthesis of a variety of organic chemicals. It can be prepared by the chlorination of benzoic acid. This article will analyze in detail the production process, reaction principle and its wide application in industry of "benzoyl chloride prepared from benzoic acid.

1. Benzoic Acid Chlorination Reaction

Benzoic acid (C6H5COOH) is a compound composed of benzene ring and carboxyl group (-COOH), which widely exists in nature and is an important organic intermediate. In industrial production, benzoic acid is often used as a raw material for the synthesis of benzoyl chloride.

The main reaction for the preparation of benzoic acid from benzoic acid is the reaction of benzoic acid with a chloride (e. g. thionyl chloride, SOCl2) to form benzoyl chloride. The basic equation for this reaction is as follows:

[ C6H5COOH SOCl2 → C6H5COCl SO2 HCl ]

in the reaction, thionyl chloride serves as the chlorine source and the carboxyl group of the benzoic acid is chlorinated to produce benzoyl chloride and release sulfur dioxide (SO2) and hydrogen chloride (HCl) gases.

2. Benzoyl Chloride Production Process

1. Raw material preparation: Benzoic acid is usually synthesized from petrochemical processes or from natural raw materials (such as benzene). In industry, benzoic acid is generally obtained by catalytic oxidation of benzene or benzyl alcohol.

2. Reaction process: When benzoic acid reacts with thionyl chloride, it is usually carried out under anhydrous conditions. The reaction temperature is controlled between 60-80°C to avoid side reactions. Thionyl chloride not only acts as a chlorinating agent in this reaction, but also plays a catalytic role to ensure the smooth conversion of benzoic acid to benzoyl chloride.

3. Product Isolation and Purification: After completion of the reaction, benzoyl chloride is isolated by distillation or fractional distillation. In order to ensure the purity of the product, it is usually necessary to remove by-products in the reaction, such as hydrogen chloride and sulfur dioxide, etc., by washing.

3. benzoyl chloride

As an important organic chemical, benzoyl chloride is widely used in many fields:

• Synthetic fragrances and drugs: Benzoyl chloride can be used to synthesize fragrances, flavors and intermediates of some drugs. For example, benzoyl chloride is a key intermediate in the synthesis of antibiotics such as amoxicillin.

• Production of dyes: Benzoyl chloride can also be used in the synthesis of dyes, especially in the manufacture of dye intermediates.

• Pesticide production: Benzoyl chloride is an indispensable intermediate in the production of certain pesticides, especially in the synthesis of organophosphorus pesticides, it plays a vital role.

• Plastics industry: In the plastics industry, benzoyl chloride is used in the synthesis of plasticizers, resins and other chemical additives.

4. Benzoyl Chloride Market Prospects

With the development of organic synthetic chemistry and polymer chemistry, the demand of benzoyl chloride is increasing. As an important organic synthesis intermediate, it plays an important role in the production of many industries. In the future, with the continuous expansion of the global chemical market, the market demand for benzoyl chloride is expected to increase further.

Conclusion

The process of "preparation of benzoyl chloride from benzoic acid" is simple and efficient, and benzoyl chloride is widely used in the chemical industry. From the synthesis of fragrances and pharmaceuticals to dyes, pesticides and plastics, benzoyl chloride plays an indispensable role. With the growth of market demand, the production process of benzoyl chloride will be continuously optimized to promote its application in more fields.