52334-81-3Relevant articles and documents
Catalyst-Free N-Deoxygenation by Photoexcitation of Hantzsch Ester
Cardinale, Luana,Jacobi Von Wangelin, Axel,Konev, Mikhail O.
supporting information, (2020/02/15)
A mild and operationally simple protocol for the deoxygenation of a variety of heteroaryl N-oxides and nitroarenes has been developed. A mixture of substrate and Hantzsch ester is proposed to result in an electron donor-acceptor complex, which upon blue-light irradiation undergoes photoinduced electron transfer between the two reactants to afford the products. N-oxide deoxygenation is demonstrated with 22 examples of functionally diverse substrates, and the chemoselective reduction of nitroarenes to the corresponding hydroxylamines is also shown.
METHOD FOR SEPARATING AND PURIFYING 2-CHLORO-3-TRIFLUOROMETHYLPYRIDINE
-
Paragraph 0092-0095, (2020/02/27)
A method for separating and purifying 2-chloro-3-trifluoromethylpyridine useful as an intermediate for medicines, agrochemicals, and the like is provided. The method includes: 1) in the process of producing chloro β-trifluoromethylpyridine compounds by allowing a β-methylpyridine compound to react with chlorine and hydrogen fluoride in a reaction apparatus, allowing a β-trifluoromethylpyridine compound to react with chlorine in a reaction apparatus, or allowing a chloro β-trichloromethylpyridine compound to react with hydrogen fluoride in a reaction apparatus,2) fractionating a liquid mixture containing chloro β-trifluoromethylpyridine compounds from the reaction apparatus, and3) separating and purifying 2-chloro-3-trifluoromethylpyridine from the liquid mixture.
Preparation method of 2-cholrine-5-trifluoromethyl pyridine
-
Paragraph 0025; 0026; 0030-0033, (2017/05/13)
The invention discloses a preparation method of 2-cholrine-5-trifluoromethyl pyridine. The method comprises the following steps of 1, adding a raw material 2-cholrine-5-methyl fluoride pyridine into a reaction kettle, and then adding thionyl chloride; 2, raising the temperature, and introducing chlorine into the reaction kettle; 3, after introduction of chlorine is ended, transferring the raw material into a fluorination kettle; 4, adding hydrogen fluoride which is measured well into the fluorination kettle, adding anhydrous hydrogen fluoride, raising the temperature, and conducting a reaction; 5, conducing washing and water vapor distillation on a fluoridation material, adjusting the pH value, and conducting distillation in a pressing-in rectifying tower, so that 2-cholrine-5-trifluoromethyl pyridine is obtained. According to the preparation method, thionyl chloride is adopted as solvent, so that the problem that the material contains water is solved; meanwhile, low-temperature chlorination is adopted for producing the 2-cholrine-5-trifluoromethyl pyridine chlorination material, and the foundation is laid for preparing high-purity 2-cholrine-5-trifluoromethyl pyridine.