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Huels AG
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Huels AG
Chemische Werke Huels AG
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Application filed by Huels AG, Chemische Werke Huels AGfiledCriticalHuels AG
Priority claimed from EP84110196Aexternal-prioritypatent/EP0172931B1/en
Application grantedgrantedCritical
Publication of DE3470302D1publicationCriticalpatent/DE3470302D1/en
Organic Low-Molecular-Weight Compounds And Preparation Thereof
(AREA)
Indole Compounds
(AREA)
Abstract
Prodn. of 5-membered cyclic dicarboxylic acid anhydrides, esp. citraconic anhydride (I), is effected by contacting an aq. soln. of the corresp. dicarboxylic acid with a water-insoluble tert. amine (II), sepg. the resulting salt from the aq. phase, and either (a) adding an aromatic water-azeotroping agent (IIIa), distilling off the azeotrope, opt. sepg. phases, and sepg. the anhydride from (II) by distn., or (b) adding an aliphatic azeotroping agent (IIIb), distilling off a ternary azeotrope comprising hydrolysis-stable anhydride, H2O and (IIIb), sepg.-phases, and isolating the anhydride.
DE8484110196T1984-08-281984-08-28Process for the recovery of anhydrides of dicarboxylic acids containing a 5-membered ring
ExpiredDE3470302D1
(en)
New adducts, containing epoxide groups, from polyepoxide compounds and acid polyesters of aliphatic-cycloaliphatic dicarboxylic acids, processes for their manufacture and use