Process for the synthesis of N-substituted cyclic alkylene ureas

A process for the synthesis of an N-substituted cyclic alkylene urea comprising reacting in the presence of a basic catalyst, a multifunctional aliphatic amine A having

• at least two amino groups,
• wherein at least one of the at least two amino groups is a primary amino group, —NH2, and at least one of the at least two amino groups is a secondary amino group, >NH, the other hydrogen group whereof having been substituted by a hydrocarbyl group, and
• an aliphatic organic carbonate component C selected from the group consisting of dialkyl carbonates CD, alkylene carbonates CA, and combinations thereof,
• wherein the ratio of the sum n(ps) of the amount of a substance n(-NH2) of the primary amino groups —NH2 in the multifunctional aliphatic amine A which are consumed by formation of a cyclic structure, and of the amount of a substance n(>NH) of those secondary amino groups >NH in the multifunctional aliphatic amine A which are consumed by formation of a cyclic structure, to the sum n(C) of the amount of substance n(CD) of carbonate groups of the dialkyl carbonate CD and the amount of substance n(CA) of carbonate groups in the alkylene carbonate CA, is more than 2.