Process for the production of aromatic carboxylic acid chlorides
AssigneeBayer Aktiengesellschaft
InventorsUdo Rudolph, Dieter Freitag, Ludwig Bottenbruch, Manfred Schmidt
Life of this patent
Estimating the term…
Abstract
A single-stage process for the production of pure, particularly sulphur-free, aromatic carboxylic acid chlorides by reacting an aromatic carboxylic acid containing from 1 to 3 carboxyl groups or a corresponding mixture of aromatic carboxylic acids with thionyl chloride in the presence of a catalyst, wherein tertiary phosphine oxides or their reaction products with thionyl chloride and/or the acid chloride to be formed are used as catalysts, and the use of the aromatic dicarboxylic acid dichlorides and tricarboxylic acid trichlorides obtained for the production of polycondensates.
Claims3
A single-stage process for the production of an aromatic carboxylic acid chloride which comprises reacting an aromatic carboxylic acid containing from 1 to 3 carboxyl groups or a mixture of such acids with 1 to 2 mols of thionyl chloride per carboxylic acid group of said aromatic carboxylic acid or mixture thereof at a temperature of from 50.degree. to 150.degree. C. in the presence of a catalytic amount of a tertiary phosphine oxide or the reaction product thereof with thionyl chloride.
Dependencies are inferred from the claim text.