Patent ID: 6660857
Filing Date: 2003-12-09
Classification: C07D

Abstract:
A process for the preparation of &egr;-caprolactam starting from 6-aminocaproic acid, 6-aminocaproamide, 6-aminocaproic ester, 6-aminocapronitrile, oligomers or polymers of these compounds or mixtures comprising at least two of these compounds, wherein the process is performed in the presence of N-(5-carboxypentyl)-&egr;-caprolactam and/or derivative thereof in an amount of less than 50 wt. % and more than 0.1 wt. % (based on the total reaction mixture), wherein said derivative has the structural formula where Râ€² is NH2 or OR1; n is at least 1; Râ€³ is OH, NH2 or OR1; and R1 is an organic group with 1 to 20 carbon atoms.