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ChemicalBook CAS DataBase List Ethyl 4-bromobutyrate
2969-81-5

Ethyl 4-bromobutyrate synthesis

8synthesis methods
-

Yield:2969-81-5 93.47%

Reaction Conditions:

Stage #1: ?-butyrolactonewith hydrogen bromide at 20 - 40;
Stage #2: ethanol at 40;

Steps:

1 Experimental group 1:

Add 200g γ-butyrolactone to a 500mL three-necked flask,The control temperature is 20±5,Continue after slowly feeding the dry hydrogen bromide gas of 226g (1.2 times of amount, mol ratio),The temperature was raised to 40±5, and the stirring reaction should be continued for 1±0.5 hours.Add 140mL (1.06 times the amount, molar ratio) of absolute ethanol,Continue to control the temperature to be 40±5°C, and stir until the reaction is completed.After the reaction was completed, 200 mL of deionized water was added to wash, and the mixture was fully stirred.The layers were left to stand, the lower organic phase was taken out, and the pH was adjusted to 7.0 with saturated NaHCO3 solution.Let stand for stratification, separate the lower organic phase, add 200 mL of deionized water to wash,Stir well, stand for stratification, separate the lower organic phase,After drying with a desiccant (molecular sieve or anhydrous sodium sulfate), the product 4-bromobutyric acid ethyl ester is obtained. By gas chromatography analysis, no by-products. The yield was 93.47%, and the purity was 98.27%.

References:

CN114736119,2022,A Location in patent:Paragraph 0045-0048

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