Resolution of 2-(6-methoxy-2-napthyl)propionic acid
US3988365A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 13, 1975 |
| Grant date | Oct 26, 1976 |
| Priority date | — |
| Expiry date | Jan 13, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C59/64
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Resolution of mixtures of d and 1,2-(6-methoxy-2-napthyl)propionic acid with cinchonidine to yield the d-isomer is conducted by using, in combination with the cinchonidine, an inorganic base having a basicity, pKa, greater than 8 and forming a salt of 2-(6-methoxy-2-napthyl)propionic acid more soluble than the solubility of the corresponding cinchonidine salts. After the cinchonidine salt product is cleaved by treatment with a strong base at about room temperature in methanol, the methanolic solution is mixed with sufficient water to precipitate the cinchonidine in a form which is easy to filter. After removal of the precipitated cinchonidine, acidification yields a product enriched in d 2-(6-methoxy-2-napthyl)propionic acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.