Process for preparing naproxen
US4864063A · kind A · utility
Inventors
Key dates
| Filing date | Dec 23, 1987 |
| Grant date | Sep 5, 1989 |
| Priority date | — |
| Expiry date | Dec 23, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/00
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for preparing Naproxen via a sequence of stereospecific reactions which comprises: condensation of 1-chloro-2-methoxy-naphthalene with a (S)-2-halo-propionyl halide according to the Friedel-Crafts reaction, ketalization of the thus obtained (S)-2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)propan-1-one, rearrangement of said ketal to afford an ester, hydrolysis of the ester and removal of the chlorine atom in 5-position by hydrogenolysis. New (S) 2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)propan-1-ones.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.