Method of preparing alkoxymethylenemalonic acid esters
AssigneeDynamit Nobel Aktiengesellschaft
InventorsOtto Ackermann, Otto Bleh, deceased, Walter Rogler
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Abstract
Preparation of alkoxymethylene malonic acid ester of formula: ##STR1## wherein R and each R' is an alkyl group, by reaction of malonic acid diester and ortho formic acid triester. The reaction is performed in the presence of a carboxylic acid or a carboxylic acid anhydride and a Lewis acid. The ortho ester is initially present in amount of at least 1,4 mols per mole of the malonic acid ester starting material. Alcohol formed during the reaction is removed during the reaction.
Claims5
Process for the preparation of alkoxymethylene malonic acid ester by the reaction of malonic acid ester with orthoformic acid trialkyl ester, characterized in that malonic acid ester is contacted with the ortho ester in the presence of at least one of carboxylic acid and carboxylic acid anhydride, and a Lewis acid at 100.degree.-160.degree. C for a time sufficient for formation of the alkoxymethylene melonic acid ester, wherein the amount of ortho ester present at the beginning of the reaction is at least 1.4 moles thereof per mol of the malonic acid ester starting material, and wherein alcohol formed during the reaction is removed during the reaction.
Dependencies are inferred from the claim text.