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ChemicalBook CAS DataBase List Cyclobutane-1,2,3,4-tetracarboxylic dianhydride
4415-87-6

Cyclobutane-1,2,3,4-tetracarboxylic dianhydride synthesis

4synthesis methods
Preparation of 1,2,3,4- cyclobutanetetracarboxylic acid dianhydride (CBDA)To a 2L quartz glass photoreactor equipped with sixteen UV lamps (300nm) , a stirrer and a cooler were attached and 250ml of ethyl acetate and 100g of maleic anhydride were added thereto followed by stirring for complete mixing. To avoid an excessive temperature increase, an air-cooling type cooler was first run and then UV light was illuminated for a photoreaction for 24h with stirring so as not to have the reactants adhered to the reactor walls. As a result, 71g of white solid was obtained. After the filtration, the white solid was dried for 24h in a vacuum dryer at 60°C Thus-obtained solid was then added to acetic anhydride, dissolved therein and slowly heated to 150°C followed by the reaction for 24h . Hot reaction solution was filtered through a filter paper to remove impurities and kept in a freezer at the temperature of 0°C or less for recrystallization for 24h to obtain a yellow solid. Thus-obtained solid was filtered and washed three times with 1,4-dioxane to remove acetic anhydride, and then dried in a vacuum oven at 60°C for 48h to obtain 64g of 1, 2, 3, 4 -cyclobutane tetracarboxylic acid dianhydride (CBDA) .

4415-87-6.png

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Yield:4415-87-6 92.5%

Reaction Conditions:

with acetic anhydride at 100; for 24 h;Inert atmosphere;

Steps:

1.3

(3) 19.0 g of cyclobutanetetracarboxylic acid obtained in step (2) was added to 190 g of acetic anhydride, stirred and heated to 100 °C for 24 h under nitrogen protection, cooled to 10 °C and filtered, the filter cake was added with 100 mL of acetone and heated to reflux, boiled Washed for 2 hours, cooled to 10°C, filtered, rinsed with acetone, and dried to obtain 14.8 g of cyclobutanetetracarboxylic dianhydride with a yield of 92.5% and a purity of 99.3%.

References:

CN114516882,2022,A Location in patent:Paragraph 0009; 0035-0036; 0039

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