Process for preparing n-alkyllactams

Abstract

A process for preparing an N-alkyllactam, comprising the steps of: (a) reacting a lactam with an alkali metal alkoxide at 130.degree.-170.degree. C. and removing the alcohol formed by distillation; (b) reacting the product from step (a), if desired in a mixture with the product from step (e), with an alkyl halide in a solvent which is (i) an ethylene glycol dialkyl ether of the formula R--O--(CH.sub.2 --CH.sub.2 --O).sub.m R, where R in C.sub.1 -C.sub.4 -alkyl and m is 1-8, (ii) the N-alkyllactam to be prepared or (iii) a mixture of (i) and (ii), to obtain crude N-alkylactam or an alkali metal salt; (c) separating the alkali metal salt from the crude N-alkylactam; (d) subjecting the N-alkyllactam crude product to high-purity distillation after addition of a sufficient amount of alkali metal alkoxide to convert any unreacted lactam to a salt; and (e) recycling the bottom product of the distillation in step (d) in step (e) into step (b), is environmentally friendly and affords the desired N-alkyllactam in high yield and high purity.

Dependencies are inferred from the claim text.