Process for producing cyclic ureas
US4900820A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1987 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | May 22, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D243/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing a cyclic diamine which comprises reacting a diamine of the formula EQU R--HN--R'--NH--R (II) wherein R represents a lower alkyl group and R' represents a lower alkyl group-substituted dimethylene group, trimethylene group, a lower alkyl group-substituted trimethylene group, tetramethylene group or a lower alkyl group-substituted tetramethylene group with urea in the presence of a polar solvent and at 180.degree. C. or higher, to obtain a cyclic urea ##STR1## wherein R and R' are each as defined above, the production yield being more improved by carrying out the initial period reaction at 140.degree. C. or lower.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.