Process for the production of aromatic and cycloaliphatic dicarboxylic acid diamides
AssigneeAkzo N.V.
InventorsHans Zengel, Manfred Bergfeld
Life of this patent
Estimating the term…
Abstract
A dicarboxylic acid diamides is produced by reacting urea with a terephthalic, isophthalic, 2,6-naphthalene-dicarboxylic or 1,4-cyclohexane-dicarboxylic acid at an elevated temperature of about 30.degree.-200.degree. C. and in a liquid reaction medium consisting essentially of chlorosulfonic acid or an at least 10% by weight oleum. The diamide products are widely used in the preparation of pharmaceuticals and protective agents for plants.
Claims9
A process for the production of a diamide of the formula ##STR5## in which X is ##STR6## each of which is unsubstituted or substituted by a member selected from the group consisting of alkyl of 1 to 5 carbon atoms, alkoxy of 1 to 5 carbon atoms and halogen, which process comprises:
- reacting a dicarboxylic acid of the formula ##STR7## in which X has the same meaning given above, with urea at a temperature of about 60.degree. C. to 150.degree. C. in chlorosulfonic acid or an at least 10% by weight oleum as the reaction medium.
Dependencies are inferred from the claim text.