Method for the preparation of pure citalopram
US6455710B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 2002 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Jan 8, 2022 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61P25/24
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to the process for the preparation and purification of citalopram (I) in which a compound of formula (II) wherein Z is iodo, bromo, chloro or CF3—(CF2)n—SO2—O—, n being 0, 1, 2, 3, 4, 5, 6, 7 or 8, is subjected to a cyanide exchange reaction with a cyanide source; the resultant crude citalopram product is optionally subjected to some initial purification and subsequently treated with an amide or an amide-like group forming agent; the reaction mixture is then subjected to an acid/base wash and/or crystallisation and recrystallisation of citalopram in order to remove the amides formed from the crude citalopram mixture; and the resulting citalopram product is optionally further purified, worked up and isolated as the base or a pharmaceutically acceptable salt thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.