|
Succinic anhydride and ethanol as a starting material , through synthetic succinic acid monoethyl ester , succinic acid mono-ethyl chloride , 4 - ( 1 - imidazolyl ) -4 - oxobutanoate , the final synthesis product was obtained 5 - nitro-4 - oxopentanoate . And several products were IR, ~ 1H-NMR, GC, MS characterization . Through the single factor experiment to study the reaction temperature , reaction time , ratio of raw materials , catalysts, solvents on the reaction to obtain the optimum process conditions . Ethanol and succinic anhydride molar ratio of 2:1, the amount of catalyst for the succinic anhydride quality 30 % , the reaction temperature is 80 ° C , reaction time 4h, succinic acid monoethyl ester yield of 83% . The white precipitate was determined through the determination of the physical and chemical properties , succinic acid monoethyl pure product storage for one month after succinic, study the cause of its formation , and improved storage methods . Tetrahydrofuran as a solvent , imidazole and succinic acid mono-ethyl chloride in a molar ratio of 2:1, the reaction temperature is 30 ° C , reaction time 4 h , 4 - ( 1 - imidazolyl ) -4 - oxobutanoate yield reached 92% . Alkali t-butyl alcohol , potassium catalyst, nitromethane with 4 - ( 1 - imidazolyl ) -4 - oxobutanoate molar ratio of 1.5:1, and potassium tert-butyl alcohol and 4 - (1 - imidazolyl ) -4 - oxobutanoate a molar ratio of 2:1, the reaction temperature was 30 ° C , reaction time 48h, 5 - nitro-4 - oxo- pentanoate yield up to 80% .
|