Preparation method for high optical indoxacarb intermediate
US11884639B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2019 |
| Grant date | Jan 30, 2024 |
| Priority date | — |
| Expiry date | Sep 29, 2041 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/584
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A field of asymmetric catalytic synthesis, and in particular a preparation method for a high optical indoxacarb intermediate includes reacting 5-chloro-2-methoxycarbonyl-1-indanone ester (or indanone ester for short) with an oxidizing agent in the presence of a chiral Zr-salen polymer to obtain an indoxacarb intermediate (2S)-5-chloro-2,3-dihydro-2-hydroxy-1-oxo-1H-indole-2-carboxylic acid methyl ester. The yield is stabilized between 86% and 90%, and the S-enantiomer content is up to 99%. Such catalyst can replace catalysts such as cinchonine, and greatly increase the content of the effective S-enantiomer of the indoxacarb, so that the content of the hydroxyl intermediate S-enantiomer of the indoxacarb is raised from 75% to 99% or more. In addition, the chiral Zr-salen polymer catalyst is recycled without retreatment, and can be recycled at least 5 times or more, greatly reducing the production cost and laying a foundation for the industrial production of high quality indoxacarb.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.