Preparation of succinylsuccinic acid diesters
AssigneeNippon Gohsei Kagaku Kogyo Kabushiki Kaisha
InventorsMitsuhiro Goi, Masahiko Miyashita
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Abstract
Process for preparing succinylsuccinic acid diesters by subjecting .gamma.-haloacetoacetic acid esters to dimerization in the presence of a base in a mixed medium of alcohol and water containing a specific amount of a water-immiscible organic compound. The succinylsuccinic acid diesters with good quality can be prepared in high yields and can be employed effectively as intermediates for quinacridone pigment.
Claims8
In the process for preparing a succinylsuccinic acid diester by subjecting a .gamma.-haloacetoacetic acid ester to dimerization in the presence of a base in a reaction medium, the improvement which comprises carrying out the dimerization in a mixed medium of an alcohol having at least 2 carbon atoms and water containing a water-immiscible organic compound selected from the group consisting of halogenated aliphatic hydrocarbons and aromatic hydrocarbons in an amount of 0.5 to 40% by volume based on the total volume of an alcohol and water.
Dependencies are inferred from the claim text.