preparation method of 4-bromopyridine_industrial additives

background and overview of the preparation method of 4-bromopyridine

4-bromopyridine is an organic intermediate that can be obtained by bromination of pyridine with lithium carbonate or prepared by diazotization of aminopyridine.

preparation method of 4-bromopyridine

report on the preparation method of 4-bromopyridine 1.

add pyridine, liquid bromine, and ferric bromide into the reaction kettle, and react for 1-1.5 hours under calcium carbonate conditions with a rotation speed of 300-500r/min and a temperature of 40-50°c to obtain the intermediate. 4-bromopyridine.

report on the preparation method of 4-bromopyridine 2.

dissolve aminopyridine (1 mmol) and substituted copper(ii) halide in dibromo(chloro)methane (6 ml) under an argon atmosphere at 25°c, and dissolve iso-nitrous acid within 5 minutes. pentyl ester (1.1 mmol) was added dropwise to the mixture. the reaction mixture was stirred at 25 °c until gc-ms analysis of the reaction mixture showed complete consumption of starting material (16 h). the reaction mixture was added to 1n naoh (20 ml). stir the mixture for 1 hour. the mixture was extracted with ch2cl2 (3 × 20 ml). the combined organic extracts were dried (na2so4). the product was evaporated to dryness. the product was purified by column chromatography on silica gel. elution with ch2cl2 gave 4-bromopyridine.

references

[1] [chinese invention] cn202010247567.4 pvc gloves with antibacterial function and preparation method thereof

[2] tetrahedron letters, 58(17), 1681-1683; 2017