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ChemicalBook CAS DataBase List 1,2,4,5-TETRABROMOBENZENE
636-28-2

1,2,4,5-TETRABROMOBENZENE synthesis

13synthesis methods
-

Yield:636-28-2 98 %

Reaction Conditions:

Stage #1: 2,3,5,6-tetrabromoanilinewith sulfuric acid in water;
Stage #2: with sodium nitrite in water at 0;

Steps:

21 Example 21: 4,6-bis(2,4,6-triisopropylphenyl)-1,3-bis(dicyclohexylphosphino)-benzene

Add 2,3,5,6-tetrabromoaniline (4.09 g, 10.0 mmol) into a 250 mL two-neck flask, add 5.4 mL concentrated sulfuric acid (dissolved in 30 mL water), and stir for 12 h. Cool to 0°C, add sodium nitrite (1.5 g, 22.0 mmol) dissolved in 10 mL of water, and react for 4 h.Extracted three times with dichloromethane (300 mL), the organic phase was washed with 80 mL saturated sodium chloride solution, and the aqueous phase was extracted three times with dichloromethane (50 mL).The combined organic phases were dried over Na2SO4 and concentrated under reduced pressure. The residue was separated and purified by silica gel column chromatography (petroleum ether: ethyl acetate = 50:1) to obtain 3.86 g of the product with a yield of 98%.

References:

CN115385956,2022,A Location in patent:Paragraph 0096

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