695-37-4Relevant articles and documents
Visible-Light-Induced ortho-Selective Migration on Pyridyl Ring: Trifluoromethylative Pyridylation of Unactivated Alkenes
Jeon, Jinwon,He, Yu-Tao,Shin, Sanghoon,Hong, Sungwoo
supporting information, p. 281 - 285 (2019/11/26)
The photocatalyzed ortho-selective migration on a pyridyl ring has been achieved for the site-selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho-position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well-suited for addition to the C2-position of pyridinium salts to ultimately provide synthetically valuable C2-fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P-centered radicals. The utility of this transformation was further demonstrated by the late-stage functionalization of complex bioactive molecules.
Preparation method of halogenated pyridine type nitrogen oxide
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Paragraph 0030-0034, (2019/02/26)
The invention discloses a preparation method of a halogenated pyridine type nitrogen oxide. The method comprises the following steps: (1) dissolving a raw material halogenated pyridine into a solvent,adding a certain amount of an oxidizing agent, performing a reaction in a range of a reaction temperature of 0 to 40 DEG C, and after the reaction ends, obtaining a reaction product; (2) performing asubsequent postprocessing step on the reaction product obtained in the step (1) so as to obtain the target product halogenated pyridine type nitrogen oxide. The preparation method disclosed by the invention has the advantages of low reaction temperature, high yield, high purity, low cost and the like.
Synthesis method of heterocyclic compound 3-methoxypyridine
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Paragraph 0021, (2017/08/17)
The invention discloses a synthesis method of a heterocyclic compound 3-methoxypyridine. The method comprises the following steps: putting raw materials, i.e., 3-halogenated pyridine, hydrogen peroxide and acetic acid into a three-mouth flask, carrying out reaction for 4-8h at the temperature of 40-80 DEG C under the condition of stirring, recovering the acetic acid, adding a saturated sodium carbonate solution and stirring to enable a system to be alkaline, evaporating to remove water, then adding chloroform for washing, and carrying out vacuum distillation to obtain N-oxide-3-halogenated pyridine; respectively adding the N-oxide-3-halogenated pyridine, metal salt of alkyl alcohol, a catalyst A and alcohol into the three-mouth flask, carrying out reflux reaction for 5-8h under the condition of stirring, then cooling, neutralizing a product to be neutral, and carrying out distillation to obtain N-oxide-3-alkyloxypyridine; respectively adding the N-oxide-3-alkyloxypyridine, ferric trichloride, hydrazine hydrate, activated carbon and ethanol into the three-mouth flask, carrying out reaction at the temperature of 70 DEG C for 3h, cooling to room temperature, and carrying out vacuum distillation to obtain the 3-methoxypyridine. The synthesis method is high in intermediate conversion rate, mild in reaction conditions, safe in operation, low in price of raw materials and easy in raw material obtaining, thus being suitable for industrial production.