Preparation of sodium diethyl oxalacetate
AssigneeHoechst Celanese Corporation
InventorsB. Franklin Gupton, James H. Rae
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Abstract
Sodium diethyl oxalacetate is prepared in a specific manner by adding sodium ethoxide to a mixture of diethyl oxalate and ethyl acetate to obtain a free flowing sodium salt which is easily separable and purified.
Claims6
In a method of preparing sodium diethyl oxalacetate by reaction of sodium ethoxide, diethyl oxalate and ethyl acetate, the improvement which comprises adding sodium ethoxide to a mixture of diethyl oxalate and ethyl acetate while maintaining a temperature of about 0.degree. C. to 40.degree. C., reacting said ethoxide, oxalate and acetate mixture for a period of time sufficient to obtain a product mixture containing sodium diethyl oxalacetate, heating the product mixture to a temperature of 70.degree. C. to 80.degree. C. for a period of time ranging from 1/4 to 2 hours, cooling the product mixture to room temperature, and thereafter recovering sodium diethyloxalacetate.
A method of preparing sodium diethyl oxalate which comprises forming a reaction mixture by adding an 18 to 21 wt % solution of sodium ethoxide in ethanol to substantially stoichiometric amounts of diethyl oxalate and ethyl acetate while maintaining a temperature of about 5.degree. C. to 10.degree. C., stirring the reaction mixture for about 4 hours at a temperature of about 5.degree. C. to 15.degree. C. to obtain a product mixture containing sodium diethyl oxalacetate, heating the product mixture to 75.degree. C. for about 1/2 hour, cooling the product mixture to room temperature, subjecting the slurry to centrifugation to obtain sodium diethyl oxalacetate crystals, and thereafter washing the crystals with ethanol to recover a purified product.
Dependencies are inferred from the claim text.