Process for obtaining 2,5-xylenol from a 2,4-/2,5-xylenol mixture
US4247719A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1979 |
| Grant date | Jan 27, 1981 |
| Priority date | — |
| Expiry date | Jul 5, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C37/86
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The relative amount of 2,5-xylenol in a 2,4-/2,5-xylenol mixture is significantly increased by passage of the xylenol mixture together with a suitable tertiary-alkylating agent through a reactor packed with a polymer-bound sulfonic acid catalyst at temperatures of 65.degree.-95.degree. C. and, preferably, 80.degree.-90.degree. C. The product stream from such a reactor under these conditions based on a 50:50 mixture of the two isomers contains a much greater amount of 6-t-alkyl-2,4-xylenol (t-alkylated 2,4-xylenol) than 4-t-alkyl-2,5-xylenol (t-alkylated 2,5-xylenol); consequently the resulting unalkylated 2,4-/2,5-xylenol mixture is greatly enriched in 2,5-xylenol. Recovery of the unalkylated mixture by fractionation thus affords a crude 2,5-xylenol which can be further purified to give pure 2,5-xylenol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.