Process for the preparation of 3, 14.beta.-dihydroxy-17-normorphinan
US5504208A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1994 |
| Grant date | Apr 2, 1996 |
| Priority date | — |
| Expiry date | Jul 22, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D221/28
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for the preparation of 3,14.beta.-dihydroxy-17-normorphinan ##STR1## A suitable economic process for the preparation of 3,14.beta.-dihydroxy-17-normorphinan of a general formula (I) is being solved, which is a key intermediate of a semisynthetic synthesis of an effective analgesic of Butorphanol from thebaine. Synthesis includes a two step N-demethylation, and concerted dephenoxylation of 4-phenoxy-14.beta.-hydroxy-3-methoxymorphinan in the first step by means of a chloroformate, then, in the second step, by means of sodium action in a liquid ammonia, and by means of the following O-demethylation under action of a complex of aluminium chloride - dialkylsulfide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.