Molecular Formula | C6H8N2 |
Molar Mass | 108.14 |
Density | 1,27 g/cm3 |
Melting Point | 100-102 °C |
Boling Point | 256-258 °C |
Flash Point | 110°C |
Water Solubility | <0.1 g/100 mL at 20 ºC |
Solubility | H2O: 1tablet/10 mL, clear, colorless |
Vapor Presure | 0.01 mm Hg ( 25 °C) |
Vapor Density | 3.7 (vs air) |
Appearance | tablet |
Color | white to off-white |
Exposure Limit | TLV-TWA 0.1 mg/m3; carcinogenicity: A2-Suspected Human Carcinogen (ACGIH1989). |
Merck | 14,7284 |
BRN | 606074 |
pKa | 4.46(at 25℃) |
PH | 7-8 (50g/l, H2O, 20℃) |
Storage Condition | 2-8°C |
Stability | Stable. Incompatible with strong oxidizing agents. |
Sensitive | Air & Light Sensitive |
Explosive Limit | 1.5%(V) |
Refractive Index | 1.6339 (estimate) |
Physical and Chemical Properties | Colorless monoclinic crystal; Vapor pressure 0.33kPa(100 ℃); Melting point 102~104 ℃; Boiling point 252~258 ℃; Solubility: slightly soluble in cold water, soluble in ethanol, ether, chloroform; Density: relative density (Air = 1)3.7; Stability: Stable |
Use | As pesticide intermediates, dye intermediates |
Risk Codes | R20/21 - Harmful by inhalation and in contact with skin. R25 - Toxic if swallowed R36 - Irritating to the eyes R40 - Limited evidence of a carcinogenic effect R43 - May cause sensitization by skin contact R50/53 - Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. R68 - Possible risk of irreversible effects |
Safety Description | S28 - After contact with skin, wash immediately with plenty of soap-suds. S36/37 - Wear suitable protective clothing and gloves. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S60 - This material and its container must be disposed of as hazardous waste. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. S1/2 - Keep locked up and out of the reach of children. |
UN IDs | UN 1673 6.1/PG 3 |
WGK Germany | 3 |
RTECS | SS7875000 |
FLUKA BRAND F CODES | 8-10-23 |
TSCA | Yes |
HS Code | 29215119 |
Hazard Class | 6.1 |
Packing Group | III |
Toxicity | LD50 in rats (mg/kg): 1070 orally; 516 i.p., C. Burnett et al., J. Toxicol. Environ. Health 2, 657 (1977) |
colorless monoclinic crystals, darker in air and sunlight. Toxic. The melting point was 102-103 °c. Boiling Point 256~258 deg C. Slightly soluble in cold water, more soluble in hot water, soluble in ethanol, ether and chloroform. With the formation of inorganic acids soluble in water salts.
O-nitrochlorobenzene is ammoniated with ammonia at high pressure and high temperature to produce O-nitroaniline. After deamination, the reaction product is reduced and crystallized with 20% sodium sulfide at 110 ° C. And separated to obtain O-phenylenediamine.
raw materials of pesticide carbendazim, thiophanate, vat dyes and cationic dyes. It can be used as a fur dye for the preparation of a developer, a surfactant, and the like.
phenylenediamine | phenylenediamine is the simplest aromatic diamine. There are 3 isomers, namely o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine. P-phenylenediamine, also known as Usol, is a colorless crystal, which quickly oxidizes into black in the air. Boiling point 267 ℃. Soluble in water, ethanol, ether. Used as a raw material or intermediate for dyes, rubber vulcanization accelerator, developer in the photography industry, fur dye and hair dye. Those who have more contact are hair dyes, barbers and frequent hair dyes. It can enter the human body through the skin. The oxidized intermediate has different degrees of sensitization, which can cause eczema-like or lichen-like dermatitis, which mostly occurs in the skin folds of the face, neck and forearm, such as the corners of the mouth, the corners of the eyes and the nostrils. And other parts are easily damaged. Inhalation of its dust can cause bronchial asthma. The symptoms of oral poisoning are similar to those of aniline poisoning. Mainly take symptomatic treatment. O-phenylenediamine is also called 1, 2-diaminobenzene, 1, 2-phenylenediamine. Those precipitated from water are white to light yellow leaf-like crystals, and those precipitated from chloroform are prismatic crystals. It is easy to change color when exposed to the air, from white to yellow, brown, purple, and finally black. Relative density 1.2698. Melting point 103~104 ℃. Boiling point 256~258 ℃. Slightly soluble in cold water (4.15 at 35 ℃), soluble in hot water (733 at 81 ℃), ethanol, ether, chloroform and benzene. It reacts with inorganic acids to form water-soluble salts; the aqueous solution reacts with carbon disulfide to form 2-mercaptobenzimidazole; it reacts with carbon dioxide under pressure to form benzimidazolone. This product is toxic. After inhalation, it causes visual impairment, contacts with the skin, causes inflammation, enters the eyes, and also causes inflammation. Rat oral LD501070mg/kg. m-phenylenediamine is a rhomboid crystal, which is rapidly oxidized to yellowish brown in the air. Specific gravity 1.139. Melting point 62.8 ℃, boiling point 284 ℃. Soluble in water, alcohol, ketone, etc. Used in dye chemical industry, and used as curing agent for plastics, etc. It can enter the human body from the respiratory tract, skin and gastrointestinal tract. Acute poisoning can occur methemoglobinemia, liver damage and hemolytic anemia. fig. 1 shows the chemical structural formulas of three isomers of phenylenediamine, o-phenylenediamine, m-phenylenediamine and p-phenylenediamine. |
chemical properties | o-phenylenediamine has more active chemical properties and can be combined with acids, aldehydes, ketones and other compounds Condensation to obtain heterocyclic compounds, oxidation, polycondensation, substitution, diazotization and other reactions can also occur. Figure 2 shows the oxidation reaction of o-phenylenediamine. Figure 3 shows the condensation reaction of o-phenylenediamine. Colorless monoclinic crystal, with darker color in air and daylight. Slightly soluble in cold water, more soluble in hot water, easily soluble in ethanol, ether and chloroform. |
toxicity | o-phenylenediamine is moderately toxic and often causes poisoning due to dust inhalation or skin absorption (the latter is the most common phenomenon). It has a strong irritating effect on the skin, can cause severe acute rash eczema, and has scab skin; inhalation of dust can cause rhinitis, bronchitis, frequent fever, causing unique asthma and vagus nerve tension due to tracheal inflammation. M-phenylenediamine can cause changes in high-iron hemoglobin, while p-phenylenediamine can cause bronchial asthma and allergic dermatitis. |
main uses and functions of phenylenediamine | phenylenediamine is used as fluorescent indicator and chromatographic analysis reagent; Used for identification of copper, gold, iron, magnesium, vanadium, ammonia, hydrogen sulfide, sulfur dioxide, chromium oxide, etc., manufacturing azo dyes, fur dyeing, photographic materials, rubber, printing and dyeing industries. (1) o-phenylenediamine is mainly used in the manufacture of pesticide fungicides (carbendazim, benomyl, thiophanate methyl, thiabendazole), reducing dyes (reduced yellow 6GD, reduced brilliant orange GR), cationic dyes (cationic brilliant yellow 10GFF), polymer stabilizers (2-mercaptobenzimidazole), heterocyclic compounds (benzimidazole and quinoxaline), photosensitive materials, surfactants, antifreeze agents, copper anticorrosive agents, etc. It is one of the formula components of hair dye, and it is also one of the commonly used organic reagents for identifying 1, 2-diketones, carboxylic acids and aldehydes in analytical chemistry. (2) m-phenylenediamine is mainly used to make dyes, such as direct sun-resistant RN, and as fur dyes, as well as azo and azo dye intermediates, to determine nitrite, and also used in ion exchange resins, block copolymers and photography; used as textile dyes, laboratory reagents, vulcanizing agents, corrosion inhibitors. It is also used as a curing agent for epoxy resin and a coagulant for cement. (3) p-phenylenediamine is mainly used to make dyes. it can be used to synthesize disperse dyes, acid dyes, direct dyes, sulfur dyes, fur dyes (fur black D) of azo dye system. it can also be used for fur dyeing and used as cosmetic hair dye ursi d, it is also used in the production of rubber anti-aging agents ("anti-aging agent DNP", "anti-aging agent DOP", "anti-aging agent DBP") and developer. |
Use | Used as an intermediate of cationic dyes, it is the main raw material of pesticide carbendazim and other antifungal agents Used as analytical reagents, fluorescent indicators, and also used in the synthesis of organic and dyes Used as pesticides, medicines, and dyes intermediates As pesticide intermediates, dye intermediates o-phenylenediamine is an intermediate of fungicides carbendazim, thiophanate-methyl and thiabendazole, as well as an intermediate of insecticide quinathion. In addition, it is an important intermediate in the dye industry. This product is an intermediate of dyes, pesticides, additives, photosensitive materials, etc. It itself is dye fur yellow brown M. It is used in the manufacture of polyamide, polyurethane, fungicides carbendazim and thiophanate, reduced dazhong GG, leveling agent, antioxidant MB, and also used in the preparation of developer, surfactant, etc. Used as an intermediate for chemical raw materials, pesticides and dyes To verify nickel and niobium, and to determine selenium by spectrophotometry. Verification of vanadium. Ozone is separated from nitrogen oxides and hydrogen peroxide. Used to distinguish nitrous acid, hydrogen peroxide and ozone. The fluorescence indicator of acid-base titration (pH ≦ 3.1 shows green fluorescence, pH ≦ 4.4 fluorescence disappears) chelating precipitant. Reducing agent. O-phenylenediamine is a peroxidase substrate suitable for ELISA enzyme-linked reactions. The substrate produces a soluble end product, orange brown, which can be read by spectrophotometer at 450nm. This OPD reaction can be terminated with 3 N HCl or 3 M H2SO4 and read at 492 nm. |
production method | o-phenylenediamine is obtained by sodium sulfide reduction method or catalytic hydrogenation reduction method using o-nitroaniline as raw material. 21% sodium sulfide solution and o-nitroaniline are added into the reduction pot, the temperature is raised to 90 ℃, the temperature is closed to 105-110 ℃, the pressure is raised to 0.1-0.2MPa, the temperature is stirred and reduced for 5 hours, the temperature is lowered to below 40 ℃, and the temperature is filtered. The filter cake is heated and melted, distilled under reduced pressure, and the fraction at 140-210 ℃(7.89kPa) is collected as o-phenylenediamine with a yield of 70-80%. The hydrogenation process is carried out in an autoclave, the reaction temperature is 95-105 ℃, the pressure is about 2MPa, and the hydrogen reaction is carried out under the action of nickel catalyst for about 1h until the hydrogen pressure does not drop. The yield of o-phenylenediamine is above 97%. There are several preparation methods. The reduction method of o-nitroaniline and sodium sulfide uses o-nitroaniline and sodium sulfide solution to react at a pressure of 98~196kPa and a reaction temperature of 105~110 ℃, or at a reaction temperature of 120~130 ℃ and normal pressure for 3~4h to obtain o-phenylenediamine. The o-nitroaniline hydrogenation reduction method uses o-nitroaniline as raw material, Laney nickel as catalyst, controls the temperature in an autoclave to 95~105 ℃, continuously passes hydrogen until the pressure does not drop, and stirs the product under 1.960 MPa pressure. Among the above two preparation methods, the purity of the product obtained by sodium sulfide reduction method is higher, the process route is more mature, and more domestic factories use this method to produce o-phenylenediamine. However, this method has poor labor protection conditions and more wastewater. However, there are still some problems in the process of catalytic hydrogenation, and industrialization needs further improvement. In addition, there is o-dichlorobenzene ammonolysis. Many units in China have conducted research, but they have not yet been industrialized. |
category | toxic substances |
toxicity classification | highly toxic |
acute toxicity | oral-rat LD50: 1070 mg/kg; Oral-mouse LD50: 366 mg/kg |
flammability hazard characteristics | open flame combustible; heating emits toxic aniline gas |
storage and transportation characteristics | warehouse ventilation and low temperature drying; Separate storage and transportation from food raw materials |
fire extinguishing agent | mist water, carbon dioxide, sand |
color index | 76010 |
(IARC) Carcinogen Classification | 2B (Vol. 123) 2020 |
NIST Chemical Substance Information | The information is: webbook.nist.gov provides (external link) |
EPA chemical information | The information is: ofmpub.epa.gov provides (external link) |
spontaneous combustion temperature | 540°C |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov provided (external link) |