Process for preparing ethyl 3-(2,5,6-trihalopyridin-3-yl)-3-oxopropionate from 2,5,6-trihalo-3-cyanopyridine
US6437140B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2001 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Nov 14, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D213/61
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The new process for preparing ethyl 3-(2,5,6-trihalopyridin-3-yl)-3-oxopropionate from 2,5,6-trihalo-3-cyanopyridine in accordance with the present invention comprises reacting 2,5,6-trihalo-3-cyanopyridine with ethyl haloacetate at the presence of a transition metal in powder in anhydrous solvent, and treating the resulting solution with HCl. In particular, the new process for preparing ETPO from THCP comprises heating 2,5,6-trihalo-3-cyanopyridine and a transition metal in powder in anhydrous solvent to the boiling point, reacting 2,5,6-trihalo-3-cyanopyridine with ethyl haloacetate by adding ethyl haloacetate dropwise to the resulting solution, cooling the resulting solution to about 10° C., adding concentrated HCl and distilled water to the resulting solution during agitation thereof, and filtering the product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.