1. Product Introduction

CAS number 103-63-9, molecular formula C₈H₉Br, molecular weight 185.06. Its key physicochemical properties are as follows:

·Physical properties: Melting point -56 ° C, boiling point 220-221 ° C, density 1.355g/mL (25 ° C), refractive index n20/D1.556, flash point 89 ° C (193 ° F), extremely low solubility in water, only 0.039g/L, appearance as a transparent colorless to light yellow liquid.

·Chemical stability: Stable in nature, but incompatible with strong oxidants, storage requires 2-8 ° C conditions

Application Fields and Market Value of β - Bromobenzene Ethane

pharmaceutical field

·Intermediate for drug synthesis: Used for the synthesis of key intermediates for the anti asthma drug Prenside (such as 4- (4-phenylbutoxy) benzoic acid). Prenside, as a leukotriene receptor antagonist, has significant therapeutic effects on various types of asthma and allergic rhinitis.

·Other drugs: Participate in the synthesis of insecticides, antihypertensive agents, and other pharmaceutical products.

industrial sector

·Flame retardant intermediate: Synthesis of high-efficiency brominated flame retardant polybrominated styrene.

·Functional materials: used as coagulants, dispersants, fiber dyeing modifiers, antistatic agents, viscosity regulators for photosensitive materials, and electroplating gloss agents.

2. Principle

Under the catalytic action of azobisisobutyronitrile, styrene and hydrogen bromide gas undergo anti Markovnikov addition reaction to generate β - bromophenylethane.

Reaction equation:

3. Process Description: Process Flow Block Diagram and Process Overview

Under the catalytic action of azobisisobutyronitrile, styrene reacts with hydrogen bromide gas to produce crude β - bromophenylethane, which is then subjected to crude steam gasoline, zinc oxide treatment, crude product washing, distillation, drying, and packaging to obtain the product.

4. Properties of raw materials and products

Styrene: a colorless oily liquid with an aromatic odor, insoluble in water, used for ethanol and ether. When heated or exposed to sunlight or in the presence of peroxides, it is prone to polymerization, releasing heat and causing explosions. The explosion limit is 1.1-1.6% by volume, with a freezing point (℃) of -30.63, boiling point (℃) of 145.2, relative density of 0.9043, flash point (℃) of 31.11 ℃, natural point (℃) of 490, molecular formula of C8H8. It is toxic, less toxic than benzene, and has a funny odor. As the concentration increases, the irritability increases, which can irritate the skin and respiratory system. In poorly ventilated rooms, it can also irritate the gastric mucosa. Its vapor can form explosive mixtures with air, posing a risk of combustion and explosion when exposed to open flames, high heat, or in contact with oxidants. Encountering acidic catalysts such as Lewis catalysts, Ziegler catalysts, sulfuric acid, ferric chloride, aluminum chloride, etc. can cause violent polymerization and release a large amount of heat. Its vapor is heavier than air and can spread to a considerable distance at lower levels. It will ignite and reignite when exposed to a source of fire. Eye contact: Immediately lift the eyelids, rinse with plenty of flowing water for more than 20 minutes, and seek medical attention. Skin contact: Rinse with water.

Hydrogen bromide: Molecular formula: HBr, relative molecular weight: 80.92, Class 8.1 acidic corrosive substance. Colorless liquid with a pungent sour taste. It has strong corrosiveness to most metals and can react with ordinary metals to release hydrogen gas, forming an explosive mixture with air. When it comes into contact with H foaming agent, it immediately burns and can produce highly toxic cyanide gas with cyanide. May cause irritation or burns to the skin and mucous membranes, and long-term exposure to low concentrations can cause respiratory irritation symptoms and digestive dysfunction. Skin contact: Immediately remove contaminated clothing, rinse with plenty of running water for at least 15 minutes, and seek medical attention. Eye contact: Immediately lift the eyelids and thoroughly rinse with plenty of flowing water or saline solution for at least 15 minutes. Seek medical attention. A small amount of leakage can be mixed with sand, dry lime or soda ash, or washed with a large amount of water, diluted with water, and prevented from entering the wastewater system.

Gasoline: Molecular formula: C5H12-C12H26, colorless or light yellow volatile liquid, with a special odor, insoluble in water, easily soluble in benzene, acid, etc., density: 0.7-0.79 (water=1), 3.5 (air=1), boiling point: 40 ℃ -200 ℃, flash point: -50 ℃, explosion limit: 1.3% -1.6%, flammable, its vapor can form explosive mixtures in air, and it is highly flammable and explosive when exposed to open flames and high heat. It can react violently when exposed to oxidants, and its vapor is heavier than air and can spread along low places to a considerable distance. When exposed to open flames, it can cause reignition. Extinguishing agent: foam, dry powder, carbon dioxide, water is invalid. Extinguish with ordinary protein foam or light water foam.

Azodiisobutamine: It undergoes a strengthening reaction with oxidants and can cause combustion and explosion when exposed to open flames or high heat. Impact, friction, and vibration pose a risk of combustion and explosion. Heat decomposition releases toxic gases. Toxic or its vapors are toxic. If combustion occurs due to an open flame, wet cloth, asbestos blanket, etc. can be used to cover and extinguish the fire. When extinguishing, be sure to stand at the upwind position to avoid poisoning.

β - Bromobenzene: also known as β - bromoethylbenzene, 2-phenylbromoethane, 2-bromoethylbenzene, molecular formula: C8H9Br, relative molecular weight: 185.07, colorless and transparent liquid, boiling point 220-221 ℃, relative density: 1.3589, refractive index: 1.5572, flash point: 89 ℃, miscible with ether and benzene, insoluble in water. Toxic. Skin contact: Immediately remove contaminated clothing and rinse with plenty of water. Eye contact: Immediately lift the eyelids and rinse with plenty of flowing water. During the rinsing process, continuously rotate the eyes and rinse for at least 20 minutes. Fire hazards shall be eliminated during leakage, and personnel shall be evacuated. In case of small leakage, inert materials such as sand can be used to absorb it. In case of large leakage, insoluble foam shall be used to cover it, so as to avoid large volatilization and combustion explosion.

Swallowing is harmful, skin contact is harmful, and inhalation is harmful.

Preventive measures
▷ Wear protective gloves, protective clothing, goggles, and masks

Thoroughly clean after homework and do not discharge into the environment.

Accident Response
▷ Inhalation: Move the victim to fresh air, keep breathing clear, and rest. Call the detoxification center/doctor immediately.
Skin contact: Immediately remove/take off all contaminated clothing. Gently wash with plenty of soap and water. Call the detoxification center/doctor.
Eye contact: Wash carefully with water for a few minutes. If convenient and easy to operate, remove contact lenses. Call the detoxification center/doctor immediately.
▷ Ingestion: Call the detoxification center/doctor. Rinse your mouth.
[Safe Storage]

Store in a well ventilated area and keep the container sealed.
[Disposal of Waste]
Dispose of according to the requirements of relevant national and local regulations. Suggest using incineration method for disposal. The hydrogen halide discharged from the incinerator is removed by an acid scrubber.