Process for the preparation of N,N-diaryl-ureas

摘要

N,N-Diaryl-ureas of the formula R1-NR2-CO-NH-R3 wherein R1 and R2 denote aryl and R3 denotes alkyl, aralkyl or aryl, can be prepared by a process in which a diarylamine of the formula R1-NH-R2 is reacted with an isocyanate of the formula R3-NCO wherein R1, R2 and R34 have the above meaning, in the presence of acid compounds and in the presence or absence of an inert solvent and/or diluent at elevated temperature.