The production process analysis of 4-Bromobutyl methyl ester.

Basic Information:

Aliases: 4-Bromobutyric Acid Methyl Ester, 4-Bromo-n-butyrate Methyl Ester

CAS No: 4897-84-1

Molecular Formula: C5H9BrO2

Molecular Weight: 181.03

Physical State: Colorless to pale yellow transparent liquid

Melting Point: 175-190°C

Boiling Point: 186-187°C

Density: 1.434 g/cm³

Uses: It can be used to prepare cyclopropylmethylcyanide derivatives, which are important high-activity compounds.

Methyl 4-bromobutyrate  methyl ester is an important chemical intermediate widely used in the synthesis of pharmaceuticals, pesticides, and other fine chemicals. As a brominated compound, its production process directly determines the product's quality and cost. This article will provide a detailed analysis of the production process of 4-bromobutyl methyl ester from aspects such as raw material selection, reaction conditions, and process optimization.

Overview of the Production Process

The production of Methyl 4-bromobutyrate  methyl ester is primarily achieved through a bromination reaction. The basic steps involved are as follows:

Raw Material Preparation: Methyl butyrate is used as the substrate, which undergoes bromination by reacting with bromine.

Bromination Reaction: The bromination is carried out under suitable conditions to produce 4-bromobutyl methyl ester.

Post-processing and Purification: By-products and impurities are removed to ensure product purity.

Production Process Steps

Raw Material Preparation Methyl butyrate is the core raw material for the production of 4-bromobutyl methyl ester. It is easily available and has stable reactivity. Bromine, as the brominating agent, must be carefully controlled to avoid side reactions. Additionally, suitable catalysts (such as peroxides) and inert solvents (such as dichloromethane, toluene, etc.) need to be prepared.

Reaction Conditions Methyl butyrate is mixed with bromine in a solvent for the bromination reaction, usually under the following conditions:

Temperature Control: 0-10°C; low temperatures help to avoid the formation of side products.

Catalyst: A free radical catalyst (such as benzoyl peroxide) is introduced to increase the reaction rate.

Solvent Selection: Low-polarity solvents are used to facilitate bromine dissolution and improve reaction efficiency. After the reaction, the system contains the target product, along with small amounts of unreacted raw material and by-products.

Post-processing and Purification After the reaction is complete, the target product is separated and purified through the following steps:

Neutralization: Add dilute alkaline solution to neutralize any acidic substances in the system.

Extraction: Use organic solvents to extract 4-bromobutyl methyl ester.

Distillation: Perform vacuum distillation to separate 4-bromobutyl methyl ester and increase the product purity to the industrial requirements.

Process Optimization and Challenges

Increasing Yield By controlling the bromine addition rate and optimizing the catalyst concentration, side product formation can be effectively reduced, improving the reaction yield.

Green and Environmentally Friendly Traditional bromination reactions often result in waste gas emissions. Therefore, in industrial production, it is necessary to equip waste gas absorption devices (such as NaOH solution towers) to reduce environmental impact.

Equipment Requirements Since bromine is highly corrosive, production equipment must be made of corrosion-resistant materials (such as stainless steel or enamel) to ensure safe production.

The core of the production process of 4-bromobutyl methyl ester lies in controlling the bromination reaction and optimizing the subsequent purification steps. By reasonably selecting raw materials, controlling reaction conditions, and improving separation techniques, high-quality product production can be achieved. At the same time, achieving a more environmentally friendly bromination process will be a key focus in future industrial production.