What Is Formamide?

Formamide is a compound, a colorless and transparent liquid with a slight ammonia odor. It is a raw material for synthetic medicine, perfume, dyes, etc. It can also be used as a solvent for the spinning of synthetic fibers, plastic processing, and production of lignin ink. .

Chinese name: Formamide
English name: Formamid
nickname: Amino formaldehyde
Chemical formula: CH3NO
Molecular weight: 45.04
CAS Registry Number: 75-12-7
EINECS registration number: 200-842-0
Melting point: 2-3

Boiling point: 210
Water soluble: Miscible with water
Density: 1.134 g / mL @ 25
Exterior: Colorless transparent liquid
Flash point: 154.4
Application: Used as spinning solvent and organic synthesis intermediate
Security description: S 53-45-36 / 37 / 39-26-23
Danger symbol: T
Risk description: R 61-41-37 / 38

Formamide Introduction

Chinese alias: amino formaldehyde

structure

English alias: Formamide Methanamide; Formamide, Molecular Biology Grade Methanamide, Molecular Biology Grade; Formamide, MB Grade (1.12017); FORMAMIDE HDPE

Molecular formula: CH3NO

3D model Molecular weight: 45.04

Molecular structure: (right)

Formamide physicochemical properties

Properties: Transparent oily liquid with slight ammonia odor, hygroscopic and flammable.

Relative density: 1.133 (20/4 )

Boiling point: 210 ° C.

Melting point: 2.55 ° C.

Flash point: 154 ° C (open cup)

Refractive index: nD (25 ° C) 1.4468.

Flash point:> 500 ° C.

Viscosity: (20 ° C) 2.926 mPa · s.

Incompatible materials: strong oxidants, acids, alkalis.

Solubility: Insoluble in ethers and chlorine-containing solvents, slightly soluble in benzene, miscible with water, methanol, ethanol, acetic acid, acetone, dioxane, ethylene glycol, phenol and lower esters. This product can dissolve casein, but does not dissolve albumin. Can also dissolve casein, glucose, zein, gelatin, animal glue, resin, starch, lignin, cellulose acetate, nylon and certain inorganic salts: copper, lead, zinc, tin, cobalt, iron, aluminum and nickel chloride Compounds, certain sulfates, nitrates. ^[1]

Chemical properties: The hydrolysis rate of formamide is very slow at room temperature. Increasing the temperature or adding acid and alkali can accelerate the hydrolysis. In the presence of a catalyst, hydrogen cyanide can be decomposed by heating to below 35 ° C. Formamide has two active functional groups, namely a carbonyl group and an amide group, which easily undergo chemical reactions to form many nitrogen-containing heterocyclic compounds. Formamide can react with inorganic acids to form formic acid and ammonium salts. Reacts with organic halides or alcohols in the presence of a catalyst to form formate esters. This product can also react with -diketone, -imidone, fatty couple, aromatic couple, heterocyclic couple. Can be combined with cobalt salts, copper salts and nickel salts to form complexes. When formamide meets strong dehydrating agents such as phosphorus pentoxide, it can generate hydrogen cyanide. Reacts with phosphorus pentasulfide to form thioformamide. Formamide can strongly corrode copper, brass, lead, and rubber, so care should be taken during storage and transportation. ^[1]

Formamide toxicity

Category: Toxic

Toxicity: Poisoning

Acute toxicity: LD50 6.1 g / kg in rats, 3.15 g / kg in mice. Acute symptoms are characterized by damage to the nervous system, respiratory disturbances and conjunctivitis, orthostatic convulsions, and death after 3 to 4 days. The threshold concentration of chronic inhalation is 6 ± 4mg / m3. The maximum allowable concentration in the working ambient air: 30mg / m3 (20ppm) in the US and 3mg / m3 (vapor, absorbed through the skin) in the Soviet Union. ^[1]

Formamide production method

1 Formamide method 1

The first step is the production of methyl formate from carbon monoxide and methanol in the presence of sodium methoxide. In the second step, methyl formate was re-aminated to formamide, and the reaction conditions were 80-100 ° C and 0.2-0.6 MPa. This method has fewer problems.

2 Formamide method 2

The formic acid and methanol are first esterified to form methyl formate, and then ammonolyzed to form formamide, and then distilled to separate methanol and impurities to obtain a finished product. This method has tended to be eliminated due to high costs.

3 Formamide method 3

The first step is the direct synthesis of formamide from carbon monoxide and ammonia under the action of sodium methoxide under high pressure (10-30MPa) and 80-100 .

4 Formamide method 4

Formic acid and urea method.

5 Formamide method 5

The first step is the production of ammonium formate from the interaction of formic acid and ammonia. The second part is heated to dehydrate ammonium formate to formamide.

Formamide use

Formamide has active reactivity and special dissolving ability. It can be used as an organic synthetic raw material, a paper treatment agent, a softener for the fiber industry, a softener for animal glue, and an analytical reagent for determining amino acid content in rice. In organic synthesis, there are many uses in medicine, and there are many uses in pesticides, dyes, pigments, perfumes, and auxiliaries.

Used as an intermediate to synthesize imidazole, pyrimidine, 1,3,5-triazine, caffeine, theophylline, and theobromine. Used as raw materials for dyes, perfumes, pigments, adhesives, textile auxiliaries, paper treatment agents, etc. Raw materials for producing formic acid and dimethylformamide.

It is also an excellent organic solvent, mainly used in the spinning of acrylonitrile copolymers and ion exchange resins, as well as antistatic coating or conductive coating of plastic products. In addition, it is also used to separate chlorosilanes and purify grease. Formamide can undergo a variety of reactions. In addition to three hydrogens participating in the reaction, dehydration, CO removal, introduction of amino groups, introduction of acyl groups, and cyclization can also be performed.

Take the ring combination as an example. Diethyl malonate is cyclized with formamide to obtain 4,6-dihydroxypyrimidine, an intermediate of vitamin B4. Anthranilic acid cyclizes with amide to give an antiarrhythmic, often pyrroline intermediate, quinazolone-4. 3-amino-4-ethoxycarbonylpyrazole cyclizes with formamide to give xanthine oxidase inhibitor allopurin . Ethylenediamine tetraacetic acid is cyclized with formamide to obtain the anticancer drug ethyleneimine. Cyclomethyl methyl malonate and formamide are cyclized to obtain -5-methoxy-4,6-dihydroxypyrimidine disodium, an intermediate of sulfa drugs. ^[1]

Formamide Safety Information

Dangerous goods mark T

Danger category code R61-41-37 / 38

Safety Instructions S53-45-36 / 37 / 39-26-23

WGK Germany2
RTECS number LQ0525000

Formamide Risk Overview

Health hazards: slightly irritating to the skin and occasionally cause allergies. Its vapor or mist can irritate the eyes, mucous membranes and upper respiratory tract.

Explosion hazard: This product is flammable, irritating and allergenic.

Formamide first aid measures

Skin contact: Remove contaminated clothing and rinse skin thoroughly with soap and water.

Eye contact: Raise eyelids and rinse with running water or saline. Seek medical attention.

Inhalation: Remove from the scene to fresh air. If breathing is difficult, give oxygen. Seek medical attention.

Ingestion: Drink plenty of warm water and induce vomiting. Seek medical attention.

Formamide fire protection measures

Hazardous characteristics: Combustible in case of open flame and high heat. During combustion and decomposition, toxic nitrogen oxide gas is emitted.

Hazardous combustion products: carbon monoxide, carbon dioxide, nitrogen oxides.

Fire fighting methods: Firefighters must wear gas masks and full-body firefighting suits to extinguish fire in the upwind direction. Move the container from the fire to the open space as much as possible. Spray water to keep the fire container cool until the fire is over. Containers in the fire area must be evacuated immediately if they have discolored or generate sound from a safety pressure relief device. Spray the escaped liquid with water to dilute it into a non-combustible mixture and protect firefighters with mist water. Fire extinguishing agent: water, mist water, solvent-resistant foam, dry powder, carbon dioxide, sand.

Emergency response to formamide leakage

Emergency treatment: Quickly evacuate personnel from the leaked contaminated area to a safe area and isolate them to strictly restrict access. Cut off the fire. It is recommended that emergency handlers wear self-contained positive-pressure respirators and wear protective clothing. Cut off the source of the leak if possible. Prevent from flowing into restricted spaces such as sewers and flood drains. Small leaks: Absorb with sand, vermiculite or other inert materials. It can also be rinsed with a large amount of water and diluted into the waste water system. Large spills: build dikes or dig pits for containment. Transfer to a tanker or special collector with a pump and recycle or transport it to a waste disposal site for disposal.

Formamide Handling and Storage

Handling precautions: Closed operation. Operators must be specially trained and strictly abide by the operating procedures. It is recommended that operators wear self-absorbent filter-type gas masks (half-masks), chemical safety protective glasses, anti-poison infiltration work clothes, and rubber oil-resistant gloves. Away from fire and heat sources, smoking is strictly prohibited in the workplace. Use explosion-proof ventilation systems and equipment. Prevent vapors from leaking into the workplace air. Avoid contact with oxidants, acids and alkalis. Handle with care when handling to prevent damage to packaging and containers. Equipped with the corresponding variety and quantity of fire fighting equipment and leakage emergency treatment equipment. Empty containers may be harmful residues.

Storage precautions: Store in a cool, ventilated warehouse. Keep away from fire and heat sources. It should be stored separately from oxidants, acids and alkalis. Equipped with the appropriate variety and quantity of fire equipment. The storage area should be equipped with spill emergency treatment equipment and suitable containment materials.

/ Formamide exposure control / personal protection

Engineering control: closed operation.

Respiratory protection: When the concentration in the air exceeds the standard, you must wear a self-absorption filtering gas mask (half-mask). Wear an air respirator for emergencies or evacuation.

Eye protection: Wear chemical safety goggles.

Body protection: Wear protective work clothes.

Hand protection: Wear rubber oil resistant gloves.

Other protection: Smoking is strictly prohibited at the work site. Pay attention to personal hygiene. ^[2]

Formamide disposal

Dispose of by incineration. After mixing with fuel, it is incinerated. The nitrogen oxides from the incinerator are removed by a scrubber. ^[2]

Formamide shipping information

Precautions for transportation: Before transportation, check whether the packaging container is complete and sealed. During transportation, ensure that the container does not leak, collapse, fall, or damage. It is strictly prohibited to mix and transport with oxidants, acids, alkalis, and edible chemicals. Transport vehicles and vessels must be thoroughly cleaned and disinfected, otherwise no other items may be shipped. When shipping, the installation location should be far from the bedroom and kitchen, and isolated from the engine room, power source, fire source and other parts. When transporting by road, follow the prescribed route. ^[2]

Formamide regulatory information

Regulations on the Safety Management of Chemical Dangerous Goods (promulgated by the State Council on February 17, 1987), Implementation Rules of the Regulations on the Safety Management of Chemical Dangerous Goods (Chemical Law [1992] No. 677), Regulations on the Safe Use of Chemicals in the Workplace ([1996] issued by the Ministry of Labor No. 423) and other regulations have made corresponding provisions for the safe use, production, storage, transportation, loading and unloading of chemical dangerous goods. ^[2]