| 摘要 |
Alkyl- and arylmalonic acids of the formula I <IMAGE> (I) where R1=H, C1-C12-alkyl, phenyl, C1-C4-alkylphenyl, C2-C4-dialkylphenyl, R2=C1-C12-alkyl, phenyl, C1-C4-alkylphenyl, C2-C4-dialkylphenyl or R1+R2=-CH2-CH2-, are prepared by alkaline saponification by hydrolyzing the corresponding C1-C4-alkyl esters of the malonic acid of formula I, with alkali metal hydroxide dissolved in an aqueous alkali metal salt solution containing salt at 90-100% of saturation, acidifying the hydrolysis product with a mineral acid, removing the precipitated alkali metal salt which forms upon acidification, and extracting the alkyl- and arylmalonic acid formed from the aqueous solution with the aid of an organic solvent.
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