Method for the preparation of 5-cyanophthalide
US6441201B1 · kind B1 · utility
9Cited by
15References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 27, 2001 |
| Grant date | Aug 27, 2002 |
| Priority date | — |
| Expiry date | Jul 27, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D307/88
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method for the preparation of 5-cyanophthalide in which 5-carboxyphthalide is reacted with a dehydrating agent, such as thionylchloride, and a sulphonamide, in particular sulfamide. Cyanophthalide is prepared in high yields by a convenient procedure. 5-cyanophthalide is an intermediate used in the preparation of the antidepressant drug citalopram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.