Process for the preparation of N-(ortho-alkylphenyl)-imides

A process for the preparation of a N-(ortho-alkylphenyl)-imide of the formula ##STR7## in which R.sup.1 represents a C.sub.1 -C.sub.6 -alkyl radical and

• R.sup.2 to R.sup.9 independently of each other represents hydrogen;
• optionally substituted C.sub.1 -C.sub.6 -alkyl wherein the substituents are selected from the group consisting of halogen, NO.sub.2, CN, and C.sub.1 -C.sub.6 -alkoxy;
• optionally substituted C.sub.2 -C.sub.6 -alkenyl wherein the substituents are selected from the group consisting of halogen, NO.sub.2, CN, and C.sub.1 -C.sub.6 -alkoxy, halogen;
• NO.sub.2 ;
• CN, or C.sub.1 -C.sub.6 -alkoxy,
• wherein
• R.sup.6 and R.sup.7 optionally together can form R.sup.10 --C.dbd., wherein R.sup.10 is hydrogen or C.sub.1 -C.sub.4 -alkyl or
• R.sup.7 and R.sup.8 optionally together can form a double bond,
• which comprises reacting a cyclic anhydride of the formula ##STR8## wherein R.sup.6 to R.sup.9 are defined above with an amine of the formula ##STR9## wherein R.sup.1 and R.sup.5 have the meaning given in the case of formula (I),
• optionally in the presence of an acid catalyst and optionally in the presence of a solvent which is immiscible or only slightly miscible with water but can form an azeotrope with water, at a temperature between 100.degree. to 200.degree. C. under conditions so that the water formed during the reaction is removed from the reaction mixture without the addition of a polymerization inhibitor or a dipolar solvent.