624-28-2Relevant articles and documents
Synthetic method of medicinal raw material 2 and 5 - dibromopyridine
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Paragraph 0018; 0021; 0024, (2021/10/05)
The invention relates to the technical field of preparation of dibromopyridine, and discloses a synthetic method of a pharmaceutical raw material 2 and 5 - dibromopyridine, which comprises S1: temperature rising, 2 -aminopyridine and acetic anhydride added into a four-port flask. S2: Cooling, Step S1 The raw material reaction was completely followed by a cooling treatment, followed by stirring by adding bromoethane, heating at a heating temperature of 30 - 60 (degree) C, heating time of 20 - 40 minutes, and stirring again to obtain a mixture A. S3: Monol Bromo. To the method, raw materials can be pre-mixed, so that the raw materials can be preliminarily reacted, the reaction B effect is improved, bubbles are generated after reaction, the next crystallization is facilitated, cost can be reduced through accurate control of temperature and raw materials in the process, and the method is safer and more reliable.
The difference in the CO2adsorption capacities of different functionalized pillar-layered metal-organic frameworks (MOFs)
Gao, Xiang-Jing,Zheng, He-Gen
supporting information, p. 9310 - 9316 (2021/07/12)
The excessive use of fossil energy has caused the CO2concentration in the atmosphere to increase year by year. MOFs are ideal CO2adsorbents that can be used in CO2capture due to their excellent characteristics. Studies of the structure-activity relationship between the small structural differences in MOFs and the CO2adsorption capacities are helpful for the development of efficient MOF-based CO2adsorbents. Therefore, a series of pillar-layered MOFs with similar structural and different functional groups were designed and synthesized. The CO2adsorption tests were carried out at 273 K to explore the relationship between the small structural differences in MOFs caused by different functional groups and the CO2adsorption capacities. Significantly, compound6which contains a pyridazinyl group has a 30.9% increase in CO2adsorption capacity compared to compound1with no functionalized group.
Synthesis method of 2, 5-dibromopyridine
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Paragraph 0017; 0020; 0021-0023; 0024-0026; 0028, (2020/02/17)
The invention belongs to the technical field of organic synthesis, and particularly relates to a synthesis method of 2, 5-dibromopyridine, and the method comprises the following steps: (1) adding 2-aminopyridine and acetic anhydride into a four-neck flask, refluxing, and completely reacting by thin-layer chromatography tracking; (2) when the temperature of the reaction solution in the step (1) isreduced to 20-25 DEG C, dropwise adding liquid bromine, reacting for 2-3 hours at 45-55 DEG C after completion of the dropwise adding, adding water into the system until all solids are dissolved, dropwise adding a sodium hydroxide solution, continuously reacting for 30-40 minutes when a large amount of precipitate is generated, and carrying out suction filtration, drying and recrystallization to obtain 2-amino-5-bromopyridine; and (3) adding the 2-amino-5-bromopyridine into a hydrogen bromide solution, dropwise adding a sodium nitrate solution in the presence of a catalytic amount of cuprous bromide, controlling the temperature to be -5 to15 DEG C, and reacting for 2-5 hours to obtain the 2, 5-dibromopyridine. The method has the beneficial effects of mild reaction conditions, high yield, accessible raw materials, lower cost and fewer product byproducts, reduces the composite load of later separation, and has industrial prospects.