Diphenylamine intermediate

Diphenylamine is also known as N-phenylaniline. The precipitated from dilute ethanol is monoclinic white to pale yellow leafy crystal. Aroma. The relative molecular mass is 169.23. The relative density is 1.160. The temperature of 54 to 55 ° C. The boiling point is 302 ° C, 179 ° C (2.933 × 103 Pa). Flash point 153 ° C (closed). Hard to dissolve in water (0.03 at 25 ° C), soluble in ethanol (56 ° C at 20 ° C), pyridine, methanol (57.5 at 20 ° C) and acetone, soluble in benzene, ether, glacial acetic acid, carbon disulfide and inorganic acids, in case of strong acid Salt can be formed. In case of weak acid hydrolysis. Disappeared in light. The hydrogen on the nitrogen atom may be substituted by an aryl group to form a triphenylamine; it may also be substituted by a metal; under certain conditions, it may be substituted by an alkyl group and an acyl group. The aryl para position can be alkylated by an olefin under the action of a strongly acidic catalyst. Alkylation with an olefin can be carried out ortho to the aryl group under the action of an aminoaluminum catalyst. Dehydrogenation under the action of a catalyst can produce carbazole; hydrogenation produces a bicyclic lipid amine. It can be chlorinated, brominated, and nitrated to form the 2,2'-position and the 4,4'-position compound. When oxidized with potassium permanganate in an acetone solution, two amino groups can be coupled to form tetraphenylphosphonium. This product reacts with sulfur to form thipenem. It stimulates the skin and mucous membranes and produces methemoglobin. The symptoms of poisoning are similar to aniline, but lighter than aniline. Rat oral LD503000mg/kg. The maximum allowable concentration in the workplace is 10 mg/m3. Physical and chemical properties, colorless crystalline solid with aromatic odor. Density d420 1.159, melting point 53-54 ° C, boiling point 302 ° C, flash point 153 ° C. Almost insoluble in water, 0.03% solubility in water at 25 ° C. Methanol is 57.5%, ethanol is 45.5%, n-propanol is 22.2%, and it is soluble in benzene, ether, glacial acetic acid and carbon disulfide. It forms a salt with a strong acid. After daylight, the color turns yellow and deep. Diphenylamine sulfate is a white or slightly yellow crystalline powder, melting point 123 ~ 125 ° C, almost insoluble in water, soluble in ethanol, sulfuric acid. Diphenylamine hydrochloride is crystalline, blue in the air, and easily soluble in water and ethanol. Main use 1, used as dye raw material, preparation of acid yellow 36, acid orange 1, disperse orange 1 and sulfur blue 13; 2, acrylic resin polymerization inhibitor phenothiazine raw material, phenothiazine can also be used as fungicide and insect repellent 3; used as a raw material for rubber amine anti-aging agent, such as anti-aging agent 810-NA, 3C, BA, B and AW; 4, as an analytical reagent, determination of NO3-, ClO3- and SO42-, Blue; 5, also used as a nitrocellulose explosive stabilizer; 6, liquid desiccant; 7, with the product after treatment of paper wrapped fruit, can prevent fruit lesions. Toxicity The acute oral LD50 of guinea pigs is 300 mg/kg, and the tolerance per kilogram of body weight per day is 0.02 mg, which is toxic to fish. Formulation 31% emulsifiable concentrate; 35% liquid preparation; 83% wettable powder. Mode of action Diphenylamine has bactericidal, antiseptic and biomodulating activity, and is used for post-harvest treatment of apples and pears to prevent fruit injuries occurring on the peel during storage. It is used as both a plant growth regulator and a fungicide, and can be used as a control for the control of spiral flies. Method of use Before the harvest, spray in the orchard at a concentration of 2000 mg/L, so that all the fruits have drops of the drug, and then harvested and stored within 36 hours. For some varieties of apple trees, excessive concentrations can cause phytotoxicity. The concentration of the soaked fruit is 2000 mg/L. After the fruit is harvested, it must be treated within 7 days. The time of soaking the fruit should not exceed 30 seconds, and the temperature should be 15 to 25 °C. After soaking, wait for the liquid to drip slightly, then put it into storage. Dilute the water to 5000mg/L with emulsifiable concentrate, soak the wrapping paper, and wait until it is slightly dry. Soak the fruit and do not wrap it in paper. Note 1. Pay attention to protection when handling. 2. Store in a cool, ventilated place. Take care to prevent freezing. The preparation method is prepared by heating aniline hydrochloride and aniline at about 260 ° C; or nitrobenzene can be used as a starting material for synthesis. 1 Aniline and its hydrochloride are condensed at 210-240 ° C and 0.62 MPa for 2 h, and the product is boiled together with dilute hydrochloric acid to remove unreacted aniline, and finally the crude [1] is distilled and purified. 2 gas phase method. The aniline is used as a raw material, and aluminum hydride is used as a catalyst. The aniline is gasified at 300-330 ° C and a pressure of 0.4 to 10.5 MPa to carry out a gas-solid phase catalytic reaction, which can be obtained [1]. The ammonia produced during the reaction is absorbed and the unreacted aniline return system continues to be used. Analytical method Gas chromatography. References An Jiayu editor; Bao Wenzhao, Wang Boying, Li Shunping, co-edited. Practical Fine Chemicals Dictionary. Beijing: China Light Industry Press. 2000. Page 100. Gu Yidong, editor. Chemical Dictionary. Shanghai: Shanghai Dictionary Press.1989 Page 30. Wang Zhenrong, Li Buqing, ed. Pesticide Commodities Daquan. Beijing: China Business Press. 1996. p. 857.