7463-30-1Relevant articles and documents
Preparation method of 2, 5-dibromo-3-methylpyridine
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Paragraph 0017; 0020-0021; 0023-0024; 0026-0027, (2020/03/09)
The invention belongs to the field of organic synthesis, and particularly relates to a preparation method of 2, 5-dibromo-3-methylpyridine. The preparation method comprises the following steps: (1) adding 2-amino-3-methylpyridine and acetic anhydride into a four-neck flask, heating to reflux, and carrying out thin-layer chromatography tracking reaction; (2) when the temperature of a reaction liquid obtained in the step (1) is reduced to 20-25 DEG C, dropwise adding liquid bromine, reacting for 2-3 hours at 50-60 DEG C after dropwise adding of liquid bromine, adding water until all solids are dissolved, dropwise adding a sodium hydroxide solution, continuously reacting for 30 minutes after dropwise adding, and carrying out suction filtration, drying and recrystallization to obtain 2-amino-3-methyl-5-bromopyridine; and (3) adding the obtained 2-amino-3-methyl-5-bromopyridine into a hydrogen bromide solution, dropwise adding a saturated sodium nitrite solution under the catalysis of cuprous bromide, controlling the temperature to be -5 to 10 DEG C, and reacting for 2 to 4 hours to obtain 2, 5-dibromo-3-methylpyridine. The method provided by the invention has the beneficial effects ofmild reaction conditions, high yield, low cost and short process route, and is suitable for industrial production.
Efficient synthesis of 2-substituted 7-azaindole derivatives via palladium-catalyzed coupling and C-N cyclization using 18-crown-6
De Mattos, Marcos Carlos,Alatorre-Santamaria, Sergio,Gotor-Fernandez, Vicente,Gotor, Vicente
, p. 2149 - 2152 (2008/03/28)
A practical and straightforward preparation of various novel 2-substituted 7-azaindole derivatives from 2-amino-3-iodopyridine by a two-step procedure is described that gives the desired compounds in good overall yields. Georg Thieme Verlag Stuttgart.