ChemicalBook CAS DataBase List 3,5-Dibromopyridine

3,5-Dibromopyridine synthesis

12synthesis methods

Product Name:3,5-Dibromopyridine
CAS Number:625-92-3
Molecular formula:C5H3Br2N
Molecular Weight:236.89

3,5-Dibromopyridine is a heterocyclic derivative and can be used as a pharmaceutical intermediate. 3,5-Dibromopyridine can be synthesized by pyridine and bromine water through substitution reaction.

110-86-1 Synthesis

110-86-1
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625-92-3
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$6.00/10g

Yield:625-92-3 82%

Reaction Conditions:

with thionyl chloride;sulfuric acid;bromine at 130; for 10 h;Temperature;

Steps:

1-4 Example 1

As shown in Figure 1, the present invention provides a simple and feasible method for preparing 3,5-dibromopyridine, using pyridine as a raw material, concentrated sulfuric acid and thionyl chloride as a catalyst, and under high temperature conditions (high temperature refers to temperature (125-138 ) dropwise addition of bromine reaction. The specific reaction steps are:(1) Add 100g of pyridine to 100g of concentrated sulfuric acid and 300g of thionyl chloride, heat and reflux, and the mass fraction of concentrated sulfuric acid is 98%;(2) Add 550g of bromine dropwise under reflux (the addition is complete within 10 hours), and the temperature is raised to 130°C for reaction, and the reaction tube is observed for red-brown gas to determine whether the reaction is complete;(3) Steam distillation of the reaction solution, the product precipitated in the water is the crude 3,5-dibromopyridine, which does not need to be dried, and then the crude 3,5-dibromopyridine is dissolved in methanol for recrystallization and purification to obtain The yield of pure 3,5-dibromopyridine product is about 82%.

References:

CN108569999,2020,B Location in patent:Paragraph 0032-0036; 0048-0052; 0061-0065; 0074-0078

2402-99-5 Synthesis