ChemicalBook CAS DataBase List 4-HYDROXYPHTHALIC ANHYDRIDE

4-HYDROXYPHTHALIC ANHYDRIDE synthesis

7synthesis methods

Product Name:4-HYDROXYPHTHALIC ANHYDRIDE
CAS Number:27550-59-0
Molecular formula:C8H4O4
Molecular Weight:164.12

5434-21-9 Synthesis

5434-21-9
252 suppliers
$6.00/1g

27550-59-0
104 suppliers
$46.00/100mg

Yield:27550-59-0 84.6%

Reaction Conditions:

with sulfuric acid;sodium nitrite in water at 0 - 165; for 3 h;Temperature;

Steps:

1 Example 1 Preparation of 4-hydroxyphthalic anhydride
Add 100 ml of water to a 250 ml four-necked flask, 0.11 mol of 95% sulfuric acid, cool to 0-5 ° C in an ice bath, stir, and add 0.1 mol of 4-aminophthalic acid dropwise;Further, 0.105 mol of sodium nitrite was dissolved in 50 ml of water, added dropwise to a four-necked bottle, and the reaction was continued for 1.5 hours.0.5 ml of 95% sulfuric acid was added to 30 ml of water in the flask, and the diazo liquid reacted for 1.5 hours was slowly added dropwise, and the dropping process was controlled at a temperature of about 165 ° C.The distilled distillate was extracted four times with 50 ml of dichloromethane, and concentrated under reduced pressure to give 4-hydroxyphthalic acid in a yield of 93.8%.4-Hydroxyphthalic acid was sublimed in a sublimation tube at 250 ° C to obtain 4-hydroxyphthalic anhydride, and the yield was 90.2%.The total yield of 4-hydroxyphthalic anhydride was 84.6%.

References:

Xintai Zhongtai New Materials Technology Co., Ltd.;Zou Zhenbao;Ma Xindong;Zheng Junsheng CN108864009, 2018, A Location in patent:Paragraph 0019; 0020; 0023

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610-35-5 Synthesis