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ChemicalBook CAS DataBase List 4,4'-Oxydiphthalic anhydride
1823-59-2

4,4'-Oxydiphthalic anhydride synthesis

8synthesis methods
The preparation of 4,4'-Oxydiphthalic anhydride is as follows:Chlorophthalic anhydride (30g, 160mmol), tetraphenyl phosphonium bromide (0.3g, 0.7mmol), and 2,5-dichlorobenzoic acid (0.08g, 0.4mmol) were heated to approximately 220℃. Potassium carbonate (7.95g, 58mmol) was added over 45 minutes. The reaction was sampled after addition of the potassium carbonate and showed a 24.9% conversion to 4,4'-oxydiphthalic anhydride. The reaction was heated for an additional 45 minutes. The reaction mixture was diluted with 1,2,4-trichlorobenzene (90g) and filtered. The 4,4'-oxydiphthalic anhydride was allowed to crystallize and was collected, washed with 1,2,4-trichlorobenzene followed by hexane, and dried in an air circulating oven at 120℃. to give crude 4,4'-oxydiphthalic anhydride, 12.9g.

1823-59-2.png

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Yield:1823-59-2 90%

Reaction Conditions:

with bathophenanthroline in N,N-dimethyl acetamide;toluene; for 12 h;Reflux;

Steps:

30 Example 25:

General procedure: In a 25ml three-necked flask, add 4,7-diphenyl-1,10-phenanthroline (17mg, 2mol%), 4-methylphthalic acid (450mg, 2.5mmol), and finally add solvent toluene (9mL) ) and N,N-dimethylacetamide (1 ml) to help dissolve, the mixture was heated under azeotropic reflux conditions for 12 hours, and the reflux liquid was passed through molecular sieves to remove water. After the reaction was completed, the mixture was cooled and filtered to remove the solvent to obtain 4-methylphthalic anhydride in a yield of 97%.

References:

CN114213372,2022,A Location in patent:Paragraph 0045-0050

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