Process for producing diphenylmethane dicarbamates
US4552974A · kind A · utility
6Cited by
3References
33Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1983 |
| Grant date | Nov 12, 1985 |
| Priority date | — |
| Expiry date | Dec 7, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C271/06
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing a diphenylmethane dicarbamate by reacting an N-phenylcarbamate with a methylenating agent is disclosed. The process is carried out by condensing N-phenylcarbamate in two steps using a combination of two different types of acid catalysts. The catalysts exhibit a strong catalyzing effect and yet can be readily separated from the reaction mixture. The process produces dineuclear diphenylmethane dicarbamates in high selectivity. The acid catalysts can be easily recovered from the reaction mixtures and put to another use.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.