Method of increasing certain isomeric ratios in chlorinating substituted benzenes
US6222079A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1999 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | Oct 28, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C17/12
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Disclosed is a method of increasing the percentage of certain isomers made when di or tri-substituted benzenes are chlorinated in the presence of a Friedel-Crafts catalyst. The use of about 0.001 to about 1 wt % a cocatalyst during chlorination alters the isomeric ratio of the product mixture. In particular, the percentage of the 2,5-isomer is increased when said substituted benzene is ortho or meta-substituted, the percentage of the 3,4-isomer is increased when said substituted benzene is para-substituted, and the percentage of the 2,4,5-isomer is increased when said substituted benzene is 2,4-disubstituted, 3,4-disubstituted, or 2,5-disubstituted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.