624-28-2Relevant articles and documents
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.
Preparation method 2-5 - dibromopyridine
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Paragraph 0017-0025, (2021/09/21)
The invention relates to the technical field of preparation of dibromopyridine, and discloses 2-5 - dibromopyridine preparation method which comprises the following steps S1: mixing reaction, putting 2 - aminopyridine into a reactor, adding acetone, adding bromate and N -bromosuccinimide. S2: Acetone was recovered, acetone was recovered by distillation under reduced pressure, and then filtered to collect the remaining solid. S3: The finished product was prepared, the collected remaining solids were placed in a reactor, and then sodium hydroxide solution was added followed by stirring to obtain 2 - amino -5 - bromopyridine. By adding N - bromosuccinimide and heating in batches, the reaction efficiency of N - bromosuccinimide is improved, the use amount is reduced, the cost is reduced, the raw materials can be recycled by recycling acetone, the cost is reduced, 2 - amino -5 - bromopyridine yield and the purity can be improved.
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.