Method for producing 1,4-dimethylnaphthalene
US12240805B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 10, 2021 |
| Grant date | Mar 4, 2025 |
| Priority date | — |
| Expiry date | Aug 10, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2602/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides an industrial method for producing 1,4-dimethylnaphthalene with a small content of 1,3-dimethylnaphthalene. In this method for producing 1,4-dimethylnaphthalene, 5-phenyl-2-hexene is cyclized in the presence of acid catalysts to prepare crude 1,4-dimethyl-1,2,3,4-tetrahydronaphthalene, the crude 1,4-dimethyl-1,2,3,4-tetrahydronaphthalene is dehydrogenized to obtain a crude 1,4-dimethylnaphthalene, and the crude 1,4-dimethylnaphthalene is purified by distillation. In this method, the concentration of 1,3-dimethyl-1,2,3,4-tetrahydronaphthalene in 1,4-dimethyl-1,2,3,4-tetrahydronaphthalene is 1.0% or less with respect to the 1,4-dimethyl-1,2,3,4-tetrahydronaphthalene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.