PROCESS FOR PRODUCING CYCLIC UREAS

摘要

A process for producing a cyclic urea by reacting a diamine directly with phosgene with a high yield and a cheap cost is provided, which process comprises reacting a diamine expressed by the Formula R-HN-R'-NH-R wherein R represents hydrogen atom or a lower alkyl group and R' represents dimethylene group, trimethylene group, tetramethylene group or a lower alkyl group-substituted dimethylene group, trimethylene group or tetramethylene group except for three particular combinations of R with R', with phosgene substantially in the presence of water and a dehydrochlorinating agent to obtain a cyclic urea expressed by the formula wherein R and R' are as defined above.