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ChemicalBook CAS DataBase List 2,3-Naphthalenedicarboxylic Anhydride
716-39-2

2,3-Naphthalenedicarboxylic Anhydride synthesis

12synthesis methods
Add anhydrous tetrahydrofuran (its mass ratio to maleic anhydride is 1.5:1), cat-1 (0.05 mole), maleic anhydride (1 mole), and o-phthalaldehyde (1.5 mole) to the reactor. After adding triethylamine (5 moles), adjust the temperature below -40°C. Silicon tetrachloride (4 moles) was added dropwise to the reaction system and the reaction was placed at -40 °C for 4 h. The mixture was heated to reflux for 20 h. After the end of the reaction, concentrating the solution to a certain concentration with diatomaceous earth filtration. A light yellow solid, namely 2,3-Naphthalenedicarboxylic Anhydride, is obtained by precipitation, filtration, recrystallization and drying. Its yield reaches 88%.
2,3-Naphthalenedicarboxylic Anhydride
-

Yield:716-39-2 95%

Reaction Conditions:

with sulfuric acid at 50; for 7 h;Temperature;Reagent/catalyst;

Steps:

5.V

General procedure: (V) Dehydration reaction: In the concentrated sulfuric acid added Oxo acid anhydride in portion wise , and control the temperature at about 30 ° C. the mass ratio of oxo acid anhydride and concentrated acid is 1: 1.2. after completion of addition it was stirred for 5hrs, then slowly add the same volume of water and concentrated acid and stirring the reaction for 20 minutes. after filtration obtain a naphthalic anhydride.

References:

CN106748752,2017,A Location in patent:Paragraph 0055; 0062

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