Method for preparation of aromatic ether imides and for catalyst recovery therein
US4520204A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 25, 1983 |
| Grant date | May 28, 1985 |
| Priority date | — |
| Expiry date | Apr 25, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D209/48
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The yield of aromatic ether imides prepared by reacting a substituted phthalimide (such as 4-nitro-N-methylphthalimide) with an alkali metal salt of a hydroxyaromatic compound (such as the disodium salt of bisphenol A) in the presence of a phase transfer catalyst is improved by conducting the reaction in o-dichlorobenzene as diluent. When the reaction mixture is subsequently extracted with water and/or aqueous alkali, o-dichlorobenzene can also be used in recovery of the phase transfer catalyst from the aqueous phase by extraction thereof. Such recovery is improved by dissolving a substantial amount of inorganic salt in the aqueous phase and by conducting the o-dichlorobenzene extraction at elevated temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.