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ChemicalBook CAS DataBase List 2,3-Dimethylmaleic anhydride
766-39-2

2,3-Dimethylmaleic anhydride synthesis

8synthesis methods
-

Yield:-

Reaction Conditions:

Stage #1: maleic anhydride;acetic acidwith 2-aminopyridine at 100; for 0.5 h;
Stage #2: with sulfuric acid in water; for 3.2 h;Reflux;Temperature;Concentration;

Steps:

3.A A, Preparation of dimethyl maleic anhydride

maleic anhydride,2-aminopyridine and glacial acetic acid in accordance with the weight ratio of 1: 0.45: 2.5 mixed,Heated at a temperature of 100 under reflux conditions 0.5h,Then adding a concentration of 1.0mol / L sulfuric acid aqueous solution,Then heated to reflux 3.2h, cooled to room temperature,Followed by crystallization under stirring, filtered,Washed with water, dried at a temperature of 15 for 30min,Using NMR spectroscopy to determine the detection method,The product obtained by drying is colorless crystal dimethyl maleic anhydride;

References:

CN106748956,2017,A Location in patent:Paragraph 0073-0074; 0085-0086; 0097-0098; 0109-0110; 0121

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