Process for the synthesis of cyclic carbamates
US8957204B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 2011 |
| Grant date | Feb 17, 2015 |
| Priority date | — |
| Expiry date | Oct 14, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D265/18
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention is directed to a process for the preparation of a cyclic carbamate starting with a chiral propargylic alcohol and/or a suitable salt thereof, which is reacted with a cyclization agent selected from phosgene, diphosgene, triphosgene and mixtures thereof, and in that the reaction is carried out in the presence of an aqueous base, and a water-immiscible organic solvent, said organic solvent mainly comprising at least one compound selected from C2-5-alkyl C2-5-carboxylates and mixtures of at least one C2-5-alkyl C2-5-carboxylate with at least one C5-8-alkane. Another aspect of the invention is directed to a process for the synthesis of said cyclic carbamate starting described above, wherein also a process for the preparation of the chiral propargylic alcohol is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.