Chemical processes
US6635780B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 2001 |
| Grant date | Oct 21, 2003 |
| Priority date | — |
| Expiry date | Jun 14, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C201/12
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a process for the preparation of a compound of formula (I) wherein:R1 represents C1-4 haloalkyl, fluorine, chlorine or bromine; and R2 represents hydrogen or C1-4 alkoxy; which process comprises the reaction of the corresponding ortho-nitrohalobenzene of formula (II): wherein R1 and R2 are as hereinbefore defined and X represents a fluorine or bromine atom, with, when X represents a fluorine atom:(a) an alkali metal cyanide, in a non aqueous solvent, optionally in the presence of a catalyst; orwhen X represents a bromine atom:(b) cuprous cyanide, in a non aqueous solvent, optionally in the presence of a catalyst selected from an alkali metal bromide or an alkaline earth metal bromide; or(c) an alkali metal cyanide, in a non aqueous solvent, in the presence of a catalytic amount of cuprous cyanide and a phase transfer catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.