52381-06-3Relevant articles and documents
Synthesis method of 2, 5-dimethyl-3-bromopyridine
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Paragraph 0023-0024; 0027-0028; 0031-0032, (2020/03/09)
The invention relates to the field of organic chemistry, in particular to a synthesis method of 2, 5-dimethyl-3-bromopyridine. The synthesis method comprises the following steps: 1, reacting diethyl malonate with an alkali metal to generate a salt, dropwisely adding a toluene solution of 2 methyl-3-nitro-5-chloropyridine to perform condensation reaction, and decarboxylating under acidic conditionsto obtain 2, 5-dimethyl-3-nitropyridine; 2, carrying out hydrogenation reduction, suction filtration and filtrate concentration on the obtained 2, 5-dimethyl-3-nitropyridine by taking methanol as a solvent under the catalysis of Pd/C so as to obtain 2, 5-dimethyl-3-aminopyridine;, and 3, reacting the obtained 2, 5-dimethyl-3-aminopyridine with an acid to generate a salt, cooling to -9 DEG C to 4DEG C, dropwise adding liquid bromine, dropwise adding a sodium nitrite aqueous solution after dropwise adding of liquid bromine, adjusting the pH value of an obtained solution to be higher than 7 after dropwise adding of the sodium nitrite aqueous solution, and then extracting, drying and concentrating to obtain 2, 5-dimethyl-3-bromopyridine. The method provided by the invention has the beneficial effects of mild reaction conditions, high yield, easily available raw materials, low cost, short process route and an industrial prospect.
A 2, 5 - dimethyl -3 - bromo pyridine synthesis method
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Paragraph 0020; 0023; 0024; 0027; 0028; 0031; 0032, (2019/05/28)
The invention relates to the field of organic chemistry, in particular to a 2, 5 - dimethyl - 3 - bromo pyridine synthesis method, comprises the following steps: 1, malonic acid diethyl ester and alkali metal reaction to produce salt, then dropwise 2 methyl - 3 - nitro - 5 chloro pyridine to a toluene solution of a condensation reaction, after decarboxylation under acidic conditions shall be 2, 5 - dimethyl - 3 - nitro pyridine; 2, 2, 5 - dimethyl - 3 - nitro pyridine in under the catalysis of the Pd/C, methanol as the solvent, hydrogen reduction, filtered, the filtrate is concentrated, shall be 2, 5 - dimethyl - 3 - aminopyridine; 3, 2, 5 - dimethyl - 3 - aminopyridine first with an acid generating salt, cooling to - 9 °C - 4 °C, [...], drops the instillment sodium nitrite aqueous solution, pH adjusting solution is dropped is alkaline, and then extracted, drying, concentration, shall be 2, 5 - dimethyl - 3 - bromo pyridine. The method of the invention is beneficial effect: mild reaction conditions, high yield, and raw materials are easy, and the cost is low, the process route is short, and has industrial prospects.
PYRIDYLAMIDINE COMPOUND OR SALT THEREOF, AND AGRICULTURAL OR HORTICULTURAL FUNGICIDE COMPOSITION CONTAINING THE SAME AS ACTIVE INGREDIENT
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Page/Page column 17, (2009/09/04)
An agricultural or horticultural fungicide composition having stabilized high plant disease control effect is provided. The agricultural or horticultural fungicide composition contains a pyridylamidine compound represented by the formula (I): or a salt th