5437-33-2Relevant articles and documents
Preparation method for 3,5-dichloro-2-pyridine alcohol
-
Paragraph 0019, (2016/11/14)
The invention discloses a preparation method for 3,5-dichloro-2-pyridine alcohol. The preparation method comprises the following steps: taking 3,5,6-trichloro-2-pyridinol or 3,5,6-trichloro-2-pyridinol sodium as an initial raw material, reducing the initial raw material by zinc powder in an acidic water environment, reacting to obtain 3,5-dichloro-2-pyridine alcohol, cooling, crystallizing, filtering, washing, and drying to obtain a finished product. According to the preparation method, raw materials are easy to obtain; the used reagent is low in toxicity and has low pollution to the environment; purification methods for an intermediate product and a final product are simple and easy to operate; the yield is high.
Synthesis and Properties of N-Fluoropyridinium Salts
Umemoto, Teruo,Harasawa, Kikuko,Tomizawa, Ginjiro,Kawada, Kosuke,Tomita, Kyoichi
, p. 1081 - 1092 (2007/10/02)
Various stable N-fluoropyridinium salts with a non- or weakly nucleophilic counter anion such as TfO-, FSO3-, BF4-, ClO4-, CH3SO3- etc., or with an electron-donating or -withdrawing substituent(s) on the pyridine ring were synthesized and their properties investigated.N-Fluoropyridinium-2-sulfonates, N-fluoroquinolinium triflate, and highly hindered N-fluoro-2,6-di-t-butylpyridinium salts were also synthesized.They were synthesized by counter anion displacement reactions of unstable pyridine-F2 conpounds, fluorination of salts of pyridines with protonic acids or silyl esters with F2, and/or fluorination of Lewis acid complexes of pyridines.The scope of each method was examined in detail.Each of the N-fluoropyridinium salts was assigned as the first stable 1:1 salt structure of the pyridine nucleus and halogen atom on the basis of the spectral and elemental analysis.The stability depended on the nucleophilicity or basicity of the counter anions and electronic nature or position of the ring substituents.These results and NMR analyses clearly showed the unstable pyridine-F2 compounds to have N-fluoropyridinium fluoride salt structure.Some N-fluoropyridinium triflates were hydrolyzed and the products were examined, suggesting a unique hydrolysis mechanism.
Halopyridines. I. Synthesis of 3,5-Dichloro-2-pyridone and 2,3,5-Trichloropyridine
Shvekhgeimer, M.-G. A.,Kobrakov, K. I.,Sychev, S. S.,Promonenkov, V. K.
, p. 865 - 867 (2007/10/02)
Trichloroacetonitrile reacts with acrolein to give 2,2,4-trichloro-5-oxopentanonitrile, the cyclization of which to chloropyridines has been examined.
