Process for the preparation and purification of cis-2-methylspiro(1,3-oxathiolane-5,3′)quiniclidine hydrochloride
US8143400B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 10, 2008 |
| Grant date | Mar 27, 2012 |
| Priority date | — |
| Expiry date | Sep 16, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D497/20
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
An industrially acceptable process for the preparation and purification of cis-2-methylspiro(1,3-oxathiolane-5,3′)quiniclidine from a cis/trans mixture of isomers. Treatment of the mixture with an organic sulfonic acid generates a less soluble acid addition salt that is enriched in the cis-isomer. Recrystallization or pulping using various organic solvents allows for enrichment of the cis-isomer by filtration. These new sulfonic acid salts of the cis-isomer of 2-methylspiro(1,3-oxathiolane-5,3′)quiniclidine prepared according to the present invention could be further converted into the hydrochloride salt by any known procedures such as treatment with a base and then hydrochloric acid salt formation or exchange of the sulfonic acid salt with hydrochloric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.