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ChemicalBook CAS DataBase List 4,4'-(Hexafluoroisopropylidene)diphthalic anhydride
1107-00-2

4,4'-(Hexafluoroisopropylidene)diphthalic anhydride synthesis

10synthesis methods
-

Yield:1107-00-2 96%

Reaction Conditions:

with acetic anhydride at 120; for 4 h;Temperature;

Steps:

1.2; 15-16; 1-2

Add hexafluorotetraacid to 40ml of anhydrous acetic anhydride, stir and reflux at 120°C for 4h, the molar ratio of hexafluorotetraacid to anhydrous acetic anhydride is 1:3.5. The reaction solution was cooled by an ice-water bath to precipitate white crystals, and after drying, the crude hexafluorodianhydride was obtained with a purity of 98%.The crude hexafluorodianhydride was added to 20ml of anhydrous trifluoroacetic anhydride and mixed, and then heated to reflux at 35°C for 1.5h. The molar ratio of crude hexafluorodianhydride to anhydrous trifluoroacetic anhydride was 1:1.5. The reaction solution was cooled by an ice-water bath to precipitate white crystals, and after drying, the finished product of hexafluorodianhydride was obtained with a purity of 99.8%. The yield of S2 step was 96%.

References:

CN113480504,2021,A Location in patent:Paragraph 0026; 0030-0031; 0045-0046; 0047-0048; 0049; 0051

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